F350 Gearing choices...

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F350 Gearing choices...

Ford F834
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I know this would be a better question in the context of a build thread, but I am going to wing it out there anyway. I am trying to decide which drivetrain components to put in my F350. I have almost too many choices, and I could use some fresh input.
 
My axles are 4.10’s and I have at my disposal a 460 wide ratio ZF, a close ratio 7.3 ZF, a BW1345 transfer case with a GearVendors overdrive on it (rear axle overdrive only) and a BW1356 transfer case with some flanges to adapt a 2wd DNE2 overdrive to the rear output shaft. Below are some possibilities that I am considering:
 
1) Sell the overdrive units and re-gear the axles to 3.55’s. This would simplify the driveline and simplify operation by getting rid of the need for double overdrive. The down side is the final drive ratio (2.73) isn’t quite as tall as I want, and I would have to use the close ratio ZF for a decent start out gear. The close ratio also has a really high reverse, making back up driving obnoxious with 3.55’s unless shifted into low range on the transfer case.

2) Run the 460 ZF and GearVendors overdrive. This would be my easiest install. With 4.10’s 2nd gear starts are possible. I would have a crawl gear without shifting into low range. I would have a nice low geared reverse. The GVOD would produce a near ideal final drive ratio of 2.43 and works well as a splitter. The down side is the GVOD is a little clumsy to use with manual shift, only works in 2wd, and has a wearable conical clutch. The hydraulic pump and planetary design means that it cannot be engaged below 25 mph, and engine braking is particularly hard on the clutch (not good if you do a lot of towing in the mountains). Although Gear Vendors reps have told me it is plenty strong enough for my power level, it may not last as long as I’d like.

3) Run the 7.3 ZF and DNE2 overdrive. The reason I would pair the DNE2 with the close ratio ZF is because the DNE2 is a direct gear drive unit and can be left in either high or low range. If  left in high range, it would essentially act like a set of 3.28 axle gears. The cast iron gear case is physically about four times the size and weight of the GVOD and is rated for 35,000 lbs. combined vehicle weight. It is much more robust and has no wearable clutches. Unfortunately the electric motor shifts are slow, and not well suited to shifting in and out of overdrive as part of the normal driving sequence. (Same mechanism as an Eaton two speed axle). It has no lockout to prevent engagement in 4x4 which could result in severe vehicle damage if misused. Again the high reverse ratio would be a problem (see above).

4) Mount the DNE2 directly to the ZF 5 and source a divorced NP205. This last option is a variation on option 3. The DNE2’s input is identical to a 6 bolt transfer case and can therefore be mounted directly to a 4x4 transmission. The much more rare 4x4 version is actually designed to go in between the transmission and a married transfer case. Good luck finding one of those! But I can find divorced NP205’s for a price. This would make it useable in 4x4, and some great driveline parking brake set ups are available for the NP205. The down side is cost of the NP205, three new drive shafts, two more U joints and a lot of cross member fabrication. Bullet proof but no doubt more driveline friction loss than other options.

There isn’t a right or best answer, I’m just curious what you all would pick in my situation. Or maybe something that I have not suggested here. Also, both ZF’s should be rebuilt, and probably the BW1356 if I use it. I’m not particularly interested in going to a ZF-6 although it can be done, and I’m not wanting to convert to automatic.
SHORT BED 4-DOOR DIESEL: 1986 F350 4x4 under construction-- 7.3 IDIT ZF5+GVOD

STRAIGHT SIX 4X4: 1981 F150 2wd to 4x4-- 300 I6 close ratio diesel T19, hydroboost brakes, Saginaw steering

BIG F: 1995 F-Superduty under construction— converting to 6.9L IDI diesel ZF5+DNE2
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Re: F350 Gearing choices...

Gary Lewis
Administrator
Shades of an 8-page microanalysis!  

No, this doesn't belong buried in a build thread.  It needs to be a stand-alone topic, like this one.  So, let's get started.....

First, I get lost in all the gearing issues, numbers, etc.  So, if you'll provide me with the gear ratios I'd like to create a spreadsheet to help me/us get our heads around the possibilities.  And, that will let me compare the 2nd gear ratios with those of Big Blue, which has a fairly easy start in 2nd when running light and the 460 may have comparable torque at really low R's to the diesel.

Second, I don't like any of the combinations that would let you destroy things by placing it in 4lo.  I don't want to build things that are easily destroyed, and that looks like a prime candidate for destruction.  So I guess that w/o info on the gearing I'm knocking on Door #4.  NP205's are said to be STOUT, albeit heavy.  So that seems like the best option to make everything live w/the power you are planning for that engine to produce.  But, that begs the question of gearing, so we've come back around the bush.....

Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: F350 Gearing choices...

85lebaront2
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In reply to this post by Ford F834
Damn, interesting thoughts on all of them.

Gear Vendors unit sounds like the English Laycock de Normanville unit used on Jaguars, Austin-Heally 3000s and in a lighter version MGs. I believe either Chrysler or AMC used them in the 70s on their manual transmission cars as an option. I do know that once you have reached the needed speed they can be shifted in or out with a flip or slide of the switch. You are correct on the cone clutch being the weak link, but, there is also a sprag clutch that carries the output during the shift up or down and it is where I have personally seen failures on the MG units.

DNE2 Would it be possible to convert the shifting system from a worm drive electric motor to either a vacuum or air pressure system? This could also incorporated a 4X4 lockout similar to the late model shifter interlocks (depress brake to shift from Park)

Gearing I am running a 3.55 rear in Darth, plenty of power and pretty good acceleration even with a well used low compression (lower than normal due to early EFI heads on a carbureted short block). I can even, if I stomp the throttle from a standstill light all 4 rear tires.
Bill AKA "LOBO" Profile

"Getting old is inevitable, growing up is optional" Darth Vader 1986 F350 460 converted to MAF/SEFI, E4OD 12X3 1/2 rear brakes, traction loc 3:55 gear, 160 amp 3G alternator Wife's 2011 Flex Limited Daily Driver 2009 Flex Limited with factory tow package Project car 1986 Chrysler LeBaron convertible 2.2L Turbo II, modified A413

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Re: F350 Gearing choices...

Gary Lewis
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I was wondering about a lockout as well, but I'm thinking electrical is easier.  Just put a relay in the circuit from the t-case.
Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: F350 Gearing choices...

Nothing Special
One of my many plans for my '97 F-250 (and maybe I'll implement a few of them!) is to add a Gear Vendors to go with the 460, E4OD and 4.10 gears.  I forget the Gear Vendors ratio, but as I recall, it would give me about a 3.2 axle ratio (not considering the trans gearing).  That seemed like a great cruising ratio while still letting me keep the GCWR of the 4.10 ratio.  (I had a 351W/E4OD/3.55/33" setup in an F-150.  That actually even towed pretty well, so I'm not concerned about 3.2 with a 460 for cruising).

The Gear Vendors does have an electrical lockout to keep you from engaging it while the transfer case is in 4WD.  The thing I think you'd still need to be careful about is not shifting the transfer case into 4WD while the Gear Vendors is already engaged.  I'd assume the Gear Vendors would kick out pretty quick, but I don't imagine the transfer case would appreciate being engaged while the front and rear driveshafts were turning different speeds (assuming the hubs were already locked).  But I don't think that would be a huge issue for me.  It would just mean not being able to completely shut off my brain while driving in snow (the only time I'm likely to shift into 4WD when I might be in overdrive).  And staying alert while driving in snow is a pretty good idea anyway.

But I know nothing about the durability of the Gear Vendors.  I know a lot of people like it, but that's as far as my "knowledge" goes.  So I'm definitely interested in this thread.
Bob
Sorry, no '80 - '86 Ford trucks
"Oswald": 1997 F-250HD crew cab short box, 460, E4OD, 4.10 gears
"Pluto": 1971 Bronco, 302, NV3550 5 speed, Atlas 4.3:1 transfer case, 33" tires
"the motorhome": 2015 E-450-based 28' class C motorhome, 6.8L V-10
"the Dodge": 2007 Dodge 2500, 6.7L Cummins
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Re: F350 Gearing choices...

Ford F834
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Gary, I have over 20 spreadsheet pages dedicated to gear ratios, tire sizes, rpm at different speeds etc., I would say that I have probably put too much thought and emphasis on the ratios, and not enough on the practicality of the equipment which is why I only hinted at the ratios in my first post. I will go into the ratio choices a little more at this point, but all else being equal/similar I wanted some raw comments on the set ups themselves.
 
As you said, I am not thrilled with any of the choices. They all have some pretty hefty drawbacks. I should, however, clarify a couple of things. First, the GVOD clutch is engaged with an electric solenoid. The controller has safety lock outs to prevent engagement in 4x4, while in reverse, and below 25mph. That pretty much ensures that the really bad thing won’t happen on a 4x4 unless you bypass the controller or hotwire something. The clutch disengages instantly when power is cut to the solenoid. With the DNE2, it is electrically shifted but stays mechanically engaged. One could devise a lockout that prevents shifting while the 4x4 light is on, but once it is in overdrive there is no way to prevent moving the transfer case lever. If the hubs are locked it will be game over for the weakest link in the driveline. There is no way around it. If you set up a 2wd DNE2 on the back end of a transfer case you have to be careful. Since the hubs are manual, getting out of the truck is a good reminder not to engage it but it can still happen.
 
Both units are quite strong. I called and talked to the Gear Vendors rep several years ago and he told me the unit I have is rated for trucks up to 1,200 horsepower. He said the flywheel HP must be multiplied by the ratio of any given gear, but you can’t use it in granny low or your start out gear anyway because of the speed lockout. And even then, the horsepower rating is provided you actually gain traction at that level. He said it is almost impossible to break the GVOD. The only real issue is eventual clutch wear. This is amazing to me, since the GVOD is such a tiny little thing. It just does not look like a brute, but evidently it is tough. The DNE2 is a monster by comparison. It reminds me of maybe a half size T18. Justin Anderson has one in his moderately built IDI diesel, and has done sled pulling competitions with no ill to the overdrive. It can take whatever I might throw at it. His only complaint is that he has gone through a couple of the $125 shift motors. If you have an old style (and he does) the agar limit switch is janky and can let the motor over travel and burn up. Mine has the new solid state controller with a timer. You can also use a momentary toggle and hold it 1-2 seconds… just long enough to load the shift spring. Then at the next clutch release or easing off the throttle the shift will happen.
 
Another anecdote regarding the GVOD toughness is a story some of you may remember me telling. I was on my way over Tahachapi pass in California when my speedometer cable started to bind. This caused an intermittent signal from the speed sensor to the GVOD controller. The result was that it began slamming in and out of overdrive at 70mph. This was extremely violent. It felt like I was being rear ended by a semi over and over until I figured out what was going on and disengaged the pull switch. One of the so-called “benefits” of the GVOD is that it can be shifted under full power. I whole heartedly don’t recommend this… at least not with a standard transmission unless you like whiplash. This little event did not improve my opinion of the product. I already didn’t care for it much because of the rattling push pull switch and clunky shift into overdrive. In start/stop driving it was easy to forget to push the switch back in, so when you went to engage the overdrive it was still pulled out. You had to then push it in and pull it again by which time you lost momentum and would lug into overdrive gear. A ZF-5 would not be as bad since you would not need it until higher speed. With the T19 and 4.10’s I was in overdrive by 35-40mph, so that exercise got old driving around town.  From what I read, the DNE2 would not be fun to shift in and out of as part of your shift sequence. It takes a lot of getting used to and the shifts are slow. It would pretty much have to be left in high range (all gears 1 through 5 reduced by .80) or shifted into low range for towing heavy or 4x4 use.
 
So, about those ratios. Let me say that my baseline has been years of driving ¾ ton Fords with T18 four speeds and 4.10 axle gears with 235/85R16 tires (~31” diameter). The T18 ratios are:
 
1st 6.23 x 4.10 = 25.91
2nd 3.09 x 4.10 = 12.67
3rd 1.69 x 4.10 = 6.93
4th 1.00 x 4.10 = 4.10
 
Skipping the straight cut granny gear basically gives you a 12-7-4 three speed that begs for at least one more highway gear. This is what prompted me to use the T19 diesel transmission in my ’81. I have 4 Lo for a crawl gear if needed. As you can see it gave me roughly 12-7-4-3, and is almost perfect. It could ~maybe use a little bit more overdrive on level ground, but in hilly mountain terrain and the power level of a stock straight six I’m pretty much there. For the diesel I want a taller final drive for best mpg and cabin noise.
 
1st 4.02 x 3.00 = 12.06
2nd 2.41 x 3.00 = 7.23
3rd 1.41 x 3.00 = 4.23
4th 1.00 x 3.00 = 3.00
 
The GVOD has a reduction ratio of .78 and the DNE2 has a reduction ratio of .80, so below are some of the proposed combinations:
 
Close ratio (diesel) ZF with 3.55’s no auxiliary overdrive (everything is a little lower than desired):
1st 4.14 x 3.55 = 14.70
2nd 2.37 x 3.55 = 8.41
3rd 1.42 x 3.55 = 5.04
4th 1.00 x 3.55 = 3.55
5th 0.77 x 3.55 = 2.73
 
Close ratio (diesel) ZF with 4.10’s and GVOD (can’t split until 3rd, split 3rd and 4th are very redundant very low start out gear):
1st 4.14 x 4.10 = 16.97
2nd 2.37 x 4.10 = 9.72
3rd 1.42 x 4.10 = 5.82
3rd OD 1.11 x 4.10 = 4.54
4th 1.00 x 4.10 = 4.10
4th OD 0.78 x 4.10 = 3.20
5th 0.77 x 4.10 = 3.16
5th OD 0.60 x 4.10 = 2.46
 
Wide ratio (460) ZF with 3.55’s no auxiliary overdrive probably requires granny start out:
1st 5.72 x 3.55 = 20.31
2nd 2.94 x 3.55 = 10.44
3rd 1.61 x 3.55 = 5.72
4th 1.00 x 3.55 = 3.55
5th 0.76 x 3.55 = 2.70
 
Wide ratio (460) ZF with 4.10’s and GVOD (split 3rd possibly useful)
1st 5.72 x 4.10 = 23.45
2nd 2.94 x 4.10 = 12.05
3rd 1.61 x 4.10 = 6.60
3rd OD 1.26 x 4.10 = 5.15
4th 1.00 x 4.10 = 4.10
4th OD 0.78 x 4.10 = 3.20
5th 0.76 x 4.10 = 3.12
5th OD 0.59 x 4.10 = 2.43
 
Close ratio (diesel) ZF with 4.10’s and DNE2 in HIGH range:
1st 3.31 x 4.10 = 13.58
2nd 1.90 x 4.10 = 7.77
3rd 1.14 x 4.10 = 4.66
4th 0.80 x 4.10 = 3.28
5th 0.62 x 4.10 = 2.53
 
When my truck had the close ratio T19 and 4.10’s my 1st gear was 16.48 and it drove me nuts for casual driving while empty. It was obnoxiously low. 2nd gear was 9.88 and was pretty much impossible to start in unless slightly rolling or on a dead flat and I used lots of clutch finessing. I think that may have been partly the clutch’s fault, but a 4x4 crew cab is a lot of weight to get rolling. I believe I really need a start out gear in the 12-13 range. For overdrive gearing, 2.50 is right about optimal Justin ran the close ratio ZF, 4.10’s and the DNE2… but he also has 35” tires. If you factor that in, his final drive ratio would have been 2.13 on stock wheels. He said that he could feel it bog at inclines that you could hardly perceive visually, or in a headwind. The bogging would also show on the pyrometer in the form of rising EGT’s. He did a comparison mpg calculation and there was no difference between straight 5th gear and 5th + OD. So I am going to say that he is slightly over geared at that level. When I drove Jan’s truck to California (close ratio ZF and 3.55’s) the 2.73 drive ratio returned excellent fuel mileage, but it felt like it could use a little bit more gear at 70-75 mph freeway speeds. So I am hoping to come in around the 2.50 mark +/- with stock tires. I have run calculations with different tire sizes, but I don’t particularly want to go with bigger tires. They are expensive. The stock ones are skinny and have good traction in snow. They are relatively affordable and easy to find. I want the truck to have a more or less stock height and stance.
 
Okay, this monster post is DONE for now… welcome to my overthinking nightmare!
SHORT BED 4-DOOR DIESEL: 1986 F350 4x4 under construction-- 7.3 IDIT ZF5+GVOD

STRAIGHT SIX 4X4: 1981 F150 2wd to 4x4-- 300 I6 close ratio diesel T19, hydroboost brakes, Saginaw steering

BIG F: 1995 F-Superduty under construction— converting to 6.9L IDI diesel ZF5+DNE2
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Re: F350 Gearing choices...

Gary Lewis
Administrator
Wow!  Just WOW!  You think like I do - and I'm not sure that's a compliment.  I'm not even sure where to start.....

Ok, the last bit on the target gear ratios is really the key to me.  But, I beg to differ.  Big Blue's T-19 has the same 2nd gear (3.09) as your T-18, I think, and with 3.55's and big tires the 10.97 combined ratio is fine for starting out.  It might be ever so slightly too high, but it is quite acceptable.  And I don't think the ZF's 10.44 combo is going to be a problem since the warmed-over 351M pulled it fine in Dad's truck.  Big Blue has much larger tires, so the effective ratio was lower in Dad's, but the torque was lower as well.  And your diesel will surely have far more torque on that bottom end than even the 460.  So I think a bare wide-ratio ZF5 would do a good job on the bottom end, even with 3.55 gears, and it would be even better with 4.10's.

Then there's the cruising/top gear, and I don't have a clue what R's a diesel wants to turn, so I'll accept your 2.50 goal.  The wide-ratio ZF/GV combo comes in pretty close @ 2.43.  But, the ZF by itself isn't too far off at 2.70.  So, what is the RPM difference at 70 MPH between the two combinations?  (I'd run the numbers myself but I don't know that you said what tires you are planning on using.)  Is it enough to be worrying about?

I'm wondering if a wide-ratio ZF/3.55 setup wouldn't fit the bill pretty closely.  I know that's not what you want to do, but humor me for a minute.  Is there a way you can try that combo before moving to an overdrive setup?  I doubt it as I think you are going to need to have driveshafts made for each combination, and that's not cheap.

Speaking of cheap, what gears are in the truck now?  Changing those is a considerable expense, so maybe we should think through the costs of doing whatever you decide and see if there's an easier, cheaper solution?

Anyway, I'm just trying to come at it from another angle or perspective.
Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: F350 Gearing choices...

Ford F834
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Gary, the truck currently has 4.10 gears. So my proposal to switch to 3.55’s would entail selling off the GVOD and DNE2 to fund that venture. I realize that is probably a good $1,000 to $1,200 to have both axles done.

Perhaps my experience with 2nd gear starts had more to do with the quality and diameter of the clutch. When I removed it, it had plenty left on the friction disc and looked to be in good condition, but maybe it just wasn’t big enough for the weight of the truck? 🤷‍♂️ The ZF clutch I have to go in it is going to be a 13” Southbend SD clutch on a modified 6.9 flywheel.

As for the top end, the IDI has its torque peak at 1,400rpm. My engine was always at its very happiest between 1,500 and 2,000. For pulling, 2,000 was the sweet spot... right at 45mph with no overdrive 55mph with overdrive. I know, this was a stock compression NA 6.9, and I will be running a very modified turbocharged 7.3 with 18:1 CR. My rpm sweet spot may be higher. I can’t find my pic of the wide ratio rpm graph, but below is one for the close ratio ZF using 4.10’s and 3.55’s





Note that the 2,000 rpm sweet spot with 3.55’s in 5th is right around 67mph, with 4.10’s in 5th +OD it is 75mph on the nose.
SHORT BED 4-DOOR DIESEL: 1986 F350 4x4 under construction-- 7.3 IDIT ZF5+GVOD

STRAIGHT SIX 4X4: 1981 F150 2wd to 4x4-- 300 I6 close ratio diesel T19, hydroboost brakes, Saginaw steering

BIG F: 1995 F-Superduty under construction— converting to 6.9L IDI diesel ZF5+DNE2
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Re: F350 Gearing choices...

Ford F834
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This post was updated on .
I wish I could trial a 10-ish start out gear, but not only will the driveshaft be specific, I don’t have an easy way to simulate the gearing. I just know with the old set up 9.88 was absolutely not viable. I know ratio wise the wide ratio with 4.10’s + GVOD would nearly ideal. It would just be nice to ditch the extra gear box.

My expected power level will be around 400 hp and 800+ tq at the rear wheels. But that of course is after the turbo spools. Off the line my torque may be similar to NA, if not lower because of the 18:1 decompression. Such is the performance compromise. 😐

Edit: I know that ideally one does not pull ZF’s for fun, but hypothetically if I did regear to 3.55 I could install the wide ratio ZF without rebuilding it. If I like it, then drop and rebuild. If not, then rebuild the close ratio and swap them. It would entail some extra work, but worst case I would end up with the close ZF/3.55 combo
SHORT BED 4-DOOR DIESEL: 1986 F350 4x4 under construction-- 7.3 IDIT ZF5+GVOD

STRAIGHT SIX 4X4: 1981 F150 2wd to 4x4-- 300 I6 close ratio diesel T19, hydroboost brakes, Saginaw steering

BIG F: 1995 F-Superduty under construction— converting to 6.9L IDI diesel ZF5+DNE2
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Re: F350 Gearing choices...

grumpin
Wow! Interesting.

For me, simplicity is becoming the norm. I would go with number 1, but if financially possible I would not sell the O/D units. Never know, might need them, or change your mind.

As Lebaron said, I also have 3.55's, (always had trucks with 4.10's), the 3.55's are great, good acceleration (the 460 definitely helps!) and not too bad on the RPM's if you're not trying to keep up on a freeway. I have the C6. (So I'm the "old man" doing 60MPH!)

You can go into 4 Low for backing and other situations.

I appreciate your thoughts on the overdrives as I have thought it would be nice to have one. But well over 3 grand will buy a lot of gas!
Dane
1986 F250HD SC XLT Lariat 4x4 460 C6-Sold
1992 Bronco XLT 4x4 351W E4OD
1998 GMC Sierra SLE K1500 350 4L60E
Arizona
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Re: F350 Gearing choices...

Gary Lewis
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In reply to this post by Ford F834
Ford F834 wrote
Note that the 2,000 rpm sweet spot with 3.55’s in 5th is right around 67mph.....

....I know that ideally one does not pull ZF’s for fun, but hypothetically if I did regear to 3.55 I could install the wide ratio ZF without rebuilding it. If I like it, then drop and rebuild. If not, then rebuild the close ratio and swap them. It would entail some extra work, but worst case I would end up with the close ZF/3.55 combo.
To me, 67 MPH is a comfortable speed in these trucks, and I ran that speed pulling the boat to/from your neck of the woods a couple of years ago and never thought I was going to get run over on the interstate.  And if your sweet spot with the new engine is a bit higher then 70 or 75 MPH is very reasonable with a bare ZF.

So if you might be happy with a wide-ratio gear-set ZF, then I'd be tempted to give it a try.  And then if you really think you need taller gears then put an OD behind either ZF.
Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: F350 Gearing choices...

85lebaront2
Administrator
In reply to this post by grumpin
That was one of the reasons for wanting the E4OD. I used to have the 460 turning 2700 rpm towing at 55-60 mph with the C6, With the E4OD in 3rd I turn 2200 at 54 mph loaded, highway, 1500 rpm in 4th at 55 mph, around 1800 at 70 mph. Gas mileage varies from 10 to as high as 12.5 with a very low compression 460 and a truck that weighs 6400 lbs empty and is running 6 tires on the road.
Bill AKA "LOBO" Profile

"Getting old is inevitable, growing up is optional" Darth Vader 1986 F350 460 converted to MAF/SEFI, E4OD 12X3 1/2 rear brakes, traction loc 3:55 gear, 160 amp 3G alternator Wife's 2011 Flex Limited Daily Driver 2009 Flex Limited with factory tow package Project car 1986 Chrysler LeBaron convertible 2.2L Turbo II, modified A413

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Re: F350 Gearing choices...

Gary Lewis
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Big Blue is turning 2500 R's at 65 MPH, and has enough torque to tow a trailer w/another pickup on it easily at that speed.  So when I go to the ZF5 I'll just tow in 4th and use 5th for cruising - much more quietly and efficiently than today.
Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: F350 Gearing choices...

Ford F834
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This post was updated on .
Gary, do you happen to know the curb weight of Big Blue? Do you happen to know the clutch diameter? I should measure the one that came out of my diesel. Also, I know you have mentioned it before but what tires are on Big Blue?

I am guessing that my own anti-overdrive biases have slanted the responses here, but overall I am hearing the advice of keep it simple and re-gear. The DNE2 + divorced NP205 option is still haunting me a little, since it works in 2wd and 4wd. It is like re-gearing but with the option to go back at the flip of a switch. Divorced NP205’s are quite expensive, as are 3 custom driveshafts. But maybe not that much further out of line than new axle gears? There are also the very nice driveline brakes made for the 205, but I wouldn’t necessarily have to do the DNE2 idea for that. I could find a married one to replace the 1356 that likely needs rebuilt.



Another option that ~may exist is re-gearing to 3.31’s. From what I read, this is the largest pinion gear that can fit in a Dana 60. However, the front Dana 60’s that had them were from the Expeditions in the 2000’s and I have no idea if the R&P set would fit my ‘86 kingpin Dana. Also, I don’t know if that gear exists for a Sterling 10.25, since the aforementioned Expeditions came with Sterling 10.5’s. Lastly, the only 3.31 D60 gears that I found were from Ford and were to the tune of $595 for just the gears. Hardly worth it for the little bit of edge over 3.55’s.

Edit:
On the note of comfortable driving speed, I usually have kept it down in the mid 60’s with these older trucks. That is where they handle and feel safe, as well as obtaining optimal mpg. My crew cab was kind of an exception. I think the super long wheelbase and rigid straight axle made it handle quite nice up to 75+ mph. But the noise was deafening. It pulled the strongest at 2,000 rpm, but cruised more comfortably at ~1,500-1,600rpm. With 2.50 final ratio that is 55-60mph.
SHORT BED 4-DOOR DIESEL: 1986 F350 4x4 under construction-- 7.3 IDIT ZF5+GVOD

STRAIGHT SIX 4X4: 1981 F150 2wd to 4x4-- 300 I6 close ratio diesel T19, hydroboost brakes, Saginaw steering

BIG F: 1995 F-Superduty under construction— converting to 6.9L IDI diesel ZF5+DNE2
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Re: F350 Gearing choices...

Gary Lewis
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This post was updated on .
I'm headed out, but the tires are LT285/75R16.  Don't know the diameter.  And the 1983 facts book says an F250 4x4 starts at 3994 lbs.  They you add a 460, A/C, the huge tires, dual batteries, tool box, etc.  Some have said 6500 but I'm not sure it'll go that much.

EDIT: The 1983 facts book actually says 4372 lbs for a regular cab, long bed F250 HD 4wd.  But, you have to add to that the 460 engine, dual batteries, etc.....
Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: F350 Gearing choices...

Nothing Special
Gary Lewis wrote
I'm headed out, but the tires are LT285/75R16.  Don't know the diameter....
285/75-16 = 32.8" OD, 11.2" wide
Bob
Sorry, no '80 - '86 Ford trucks
"Oswald": 1997 F-250HD crew cab short box, 460, E4OD, 4.10 gears
"Pluto": 1971 Bronco, 302, NV3550 5 speed, Atlas 4.3:1 transfer case, 33" tires
"the motorhome": 2015 E-450-based 28' class C motorhome, 6.8L V-10
"the Dodge": 2007 Dodge 2500, 6.7L Cummins
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Re: F350 Gearing choices...

Ford F834
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In reply to this post by Gary Lewis
Okay thanks. So your tires are perhaps an inch or so taller than the ones I usually use. Not a huge difference....

The weight may be considerable. Justin’s 4x4 Supercab IDI weighed in right about 7,000 lbs, and his is one of the lightest according to various threads on the subject. Mid 7,000’s to low 8,000’s are the commonly reported weights. Mine being a crew cab will probably be at least 7,000.
SHORT BED 4-DOOR DIESEL: 1986 F350 4x4 under construction-- 7.3 IDIT ZF5+GVOD

STRAIGHT SIX 4X4: 1981 F150 2wd to 4x4-- 300 I6 close ratio diesel T19, hydroboost brakes, Saginaw steering

BIG F: 1995 F-Superduty under construction— converting to 6.9L IDI diesel ZF5+DNE2
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Re: F350 Gearing choices...

85lebaront2
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The Diesel does weigh even more than a 460, then add the second battery, 4WD adds a bunch more weight. Darth is a 2WD crew cab DRW truck and empty weight on a certified scale a couple of years ago was 6400 lbs.
Bill AKA "LOBO" Profile

"Getting old is inevitable, growing up is optional" Darth Vader 1986 F350 460 converted to MAF/SEFI, E4OD 12X3 1/2 rear brakes, traction loc 3:55 gear, 160 amp 3G alternator Wife's 2011 Flex Limited Daily Driver 2009 Flex Limited with factory tow package Project car 1986 Chrysler LeBaron convertible 2.2L Turbo II, modified A413

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Re: F350 Gearing choices...

Gary Lewis
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Somewhere in my literature I have the add-on weights for each accessory.  I've found one set in the master parts catalog, but haven't found the weight to add for a 460, T-19, etc.  I also have the 2nd battery, winch, and big bumper.  But I doubt it'll exceed 6000 lbs.

On Fri, May 11, 2018 at 4:19 PM, 85lebaront2 [via Bullnose Enthusiasts] <[hidden email]> wrote:
The Diesel does weigh even more than a 460, then add the second battery, 4WD adds a bunch more weight. Darth is a 2WD crew cab DRW truck and empty weight on a certified scale a couple of years ago was 6400 lbs.
"Getting old is inevitable, growing up is optional"
Darth Vader 1986 F-350 460 converted to MAF/SEFI, E4OD 12X3 1/2 rear brakes, traction loc 3:55 gear, 160 amp 3G alternator
Wife's 2011 Flex Limited
Daily Driver 1994 Taurus LX
Project car 1986 Chrysler LeBaron convertible 2.2L Turbo II, modified A413



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Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

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Re: F350 Gearing choices...

Ford F834
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Gary,

Don’t sweat the weight details. I’m just trying to get a ballpark idea if the start out gear will work for me. I don’t know that even a thousand pounds one way or the other will make or break it. No matter what I do it is going to be apples to oranges anyway. I’m just going to have to pick a combination and run with it. I just wish it wasn’t such an ordeal to change later on with respect to driveshaft length or putting rebuild money into the wrong transmission 🙄
SHORT BED 4-DOOR DIESEL: 1986 F350 4x4 under construction-- 7.3 IDIT ZF5+GVOD

STRAIGHT SIX 4X4: 1981 F150 2wd to 4x4-- 300 I6 close ratio diesel T19, hydroboost brakes, Saginaw steering

BIG F: 1995 F-Superduty under construction— converting to 6.9L IDI diesel ZF5+DNE2
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