Issues With Big Blue!?!?!

Ooops!  Wrong "Ford"!  Sorry Steve.  I just saw the Ford and didn't read any further.  

In my VERY limited experience, driving with a front locker is like wrestling a bear while trying to drive your truck.

As for rake. The D60 with stock 350 springs will raise the front ~2", an RSK will raise that another 2, and then you can change the springs for more if you want. But at that point you'll be looking for a drop pitman arm and longer panhard or track bar.

ArdWrknTrk wrote

In my VERY limited experience, driving with a front locker is like wrestling a bear while trying to drive your truck.

From what I've read that's an apt description.  And I've also read that you shouldn't send your wife or daughter out on a snowy night in a vehicle that has one.

As for front height, 2" would be great and 4 might work.

Gary Lewis wrote

Missed the afterthought.  But, I think I addressed it.  If what I've read is right, that you do NOT turn corners under power with it in the front on slick pavement, then that has me worried already.  So having the ability to lock it when needed would be nice instead of having it come in when it wants to do so.

A TrueTrac from a Dana 44HD or Dana 50 will not fit in a Dana 60.

As far as having them in a front axle goes, I have no personal experience, so take this as the thought exercise that it is.  A rolling tire will resist moving sideways while a spinning tire doesn't care which way it slides.  So there's no question that an open diff (or unlocked selectable) is the most stable option since it makes it almost impossible to spin both tires.

That said, how likely are you to spin both front tires?  Driving on ice or in slick mud it can happen.  But with the weight of the engine on the front axle it's probably pretty easy to avoid by having a light foot in those situations.  So personally I don't think I'd sweat that too much.  (The exception might be when on an icy or muddy side-hill, people that do a lot of that seem to be some of the biggest proponents of selectable lockers.)

Another risk with a locker or limited slip in a front axle is torque steer.  With an open diff both tires are always pushing the same amount, so the torque steer from each side cancels out the other.  But with one side getting more traction than the other a TrueTrac will send more torque to that side and you will get torque steer as the front tire with traction tries to turn the steering wheel in your hands.  Will that be a problem with a TrueTrac?  I don't know.  I know that it can be terribly dangerous with an automatic locker (which is why I never suggest a front auto locker for anyone who might drive in 4WD at higher speeds).  It makes sense that an auto locker would be significantly worse at this than a TrueTrac, and a few people I've chatted with say that a TrueTrac is almost invisible in this way.  But I'd be a little concerned about a front TrueTrac if driving on snowy highways was in the trucks future.

And for what it's worth, I finally have one winter's experience with a rear TrueTrac to go with the many years experience with rear auto lockers.  I'm a little torn there.  A rear auto locker is noticeable (in a bad way) most of the time, while a TrueTrac is invisible most of the time.  But in my experience the TrueTrac isn't much, if any, more stable on truly slippery roads, while the auto locker is much more effective when you've got one tire on an ice patch and the other on bare pavement.  I'm keeping the TrueTrac in my rear axle, but I'm not sure I'd do it again.

Also for what it's worth, with one week of 'wheeling with an OX selectable locker in the front of my Bronco I do really like that.  There is a contingent that doesn't like selectables in the front (too much trouble steering when locked, and too frequently bind up and won't disengage when you want them to), but in my relatively limited experience neither was really an issue.  You can't turn the wheel while stationary with it locked and both tires planted, but it seemed to steer fine as long as I was moving.  And when it bound up  just sawing the wheel back and forth a little seemed to let it disengage pretty quickly.

So taking all of that for what it's worth, I guess I wouldn't expect you would have much trouble with a front TrueTrac with your expected usage.  But if you are getting a new axle and need to pick a new diff, then I think a selectable locker might be a better choice for you (and I like the OX).

Gary Lewis wrote

ArdWrknTrk wrote

In my VERY limited experience, driving with a front locker is like wrestling a bear while trying to drive your truck.

From what I've read that's an apt description.  And I've also read that you shouldn't send your wife or daughter out on a snowy night in a vehicle that has one.

As for front height, 2" would be great and 4 might work.

I had an auto locker in the front of an F-150 for one winter.  At slow speeds (like when four-wheeling) it was very annoying, but not terrible.  Certainly worth the annoyance if you valued the performance.  But I wouldn't even use it myself on a snowy highway after the experience I had the first time I tried to change lanes, and certainly wouldn't send anyone else out with it.  The front locker effectively made my truck a 2WD on highways until I went back to an open diff.

There are auto lockers and then there are auto LOCKERS.  And the Trutrac falls into the latter category.  Ford's unit had clutches that probably eased into full lockup.  But not the Trutrac.  When it comes in it seems to come in suddenly.  That made things interesting when the rear decided to lock up on me, but I don't think "interesting" would cover it if the front locked up.  With both rears spinning you can steer into it, but I'm guessing the only thing to do with both fronts spinning is to get off the throttle.

So, I'm more and more thinking that replacing that thing would be a good idea.  Which makes the D60 swap even more interesting.

But, saying "D60" in the same sentence as "front axle" seems strange.  Back in my day the Hemi came with a D60 in the rear axle.  So it must be a capable diff.

Guess I'd better start looking.  

I vote D60, but keep in mind they are not cheap. Most run for at least $1500 and those are pretty crusty axles which need the passenger u-bolt plates addressed, which adds even further to the cost unless you do a u-bolt flip. I picked mine up for $700, but that's because it's a less desirable ball joint version from an Aeronose.

You do have the option of Super Duty axles, 99-04 are leaf sprung, however the perches are in different spots than the older D60's, the hubs are unit bearing, and the lug pattern is 8x170. If you grab a set of front and rear axles, the lug pattern isn't an issue and you also gain four wheel disc brakes. Also, Sky Manufacturing makes a Reverse Shackle Kit that would allow you to run the proper perch spacing for the Super Duty axles.

Gary Lewis wrote

There are auto lockers and then there are auto LOCKERS.  And the Trutrac falls into the latter category....

Correction, there are limited slips and LIMITED slips (to use your form of differentiation, pun intended).  Neither the Ford Traction Lock nor the TrueTrac are lockers at all, they are both limited slip diffs, albeit completely different from each other.  The Traction Lock puts friction between the two sides so it functions like a spool until it exceeds the slip torque of the clutches.  Then it acts like an open diff, but with a fixed amount of drag between the two sides.

A TrueTrac uses worm gears to send 3.5x (or 2.5x in front axle applications) as much torque to the tire that gets more traction.  So if it takes 200 lb-ft of torque to spin the tire that gets the least traction it will send up to 700 lb-ft (or 500 lb-ft for a front application) to the other tire.  Or if it takes 0 lb-ft to spin the tire with the least traction it will send 0 lb-ft to the other tire.  In most situations a TrueTrac is much more effective than a typical Traction Lock (or any other clutch-type limited slip), but they are actually less effective when one tire gets no traction (like if it's in the air, or on ice).  But it never locks.

Automatic lockers are things like Detroit, Grizzly, LockRight, Spartan, Aussie, etc.  They actually do lock up and are what can be a nightmare on a snowy highway.  TrueTracs and typical (i.e. fairly loose) Traction Locks should be less dangerous than an auto locker in a front axle.  But of the three, a TrueTrac is the only one I'd ever even consider using in the front axle of a truck that would be driven on snowy highways.  But a selectable locker would probably be a better choice, at least in my opinion.

Having had (a) a vehicle that came factory with a Detroit Locker (1966 GT350) and (b) a pretty powerful FWD car (1985 Chrysler Lebaron convertible with a roughly 200 HP turbocharged 2.2L engine) I am familiar with the locker's behavior on snow and ice (Shelby was my daily driver for a number of years) and torque steer even though the Chrysler had the equal length axles. I can appreciate the concern in both cases.

Which is why I suggested Gary find a bricknose that had a blown engine or been hit in the rear, or rolled.
I suppose aeronose or OBS will work as well as long as it has a 3.55 R&P.
Either way, cheaper than a $1250 cross member or a $1500 D60 that needs rebuilt.

While Gary has reservations, and an awful lot of other work swapping in all the Huck parts and F-450 bits.
To replace the cross member you have to remove the engine and drop the beams, anyhow.
Then to get the donor part you'd have to remove the panhard bar and swap the TTB pivots over.... anyhow.
When you have the cross member out you're already standing where the engine was, looking at the shackles and spring mounts.... anyhow

I'm of the mind 'in for a penny in for a pound'
It would never be easier to weld in a Sky RSK. In fact it would be a pita to do it while laying underneath and trying to work around an engine.

I guess a lot depends on whether Gary can find a 460/IDI cross member by itself, and how much it costs.
Or if Gary finds a donor 350 wreck with the right R&P.

Jim - You make very good points.  The sieve-like 460 will be on the stand, and lots of things will be off for the cross member replacement, so that would be the time.  

Guess I'd better get started finding the donor!

Bob - I appreciate the correction as well as the additional info.  So, in your estimation the Trutrac is acceptable in the front, but selectable is best.  Thanks.

Why do you say Big Blues engine is "sieve like"?
Is it just the oil pan gasket, or is everything leaking?

If tightened up with a couple of seals and a set of tin gaskets you could probably offset the cost of a cross member and D60 by selling it and the L&L's that won't fit the efi heads anyhow.

Gary Lewis wrote

Bob - I appreciate the correction as well as the additional info.  So, in your estimation the Trutrac is acceptable in the front, but selectable is best.  Thanks.

That's essentially correct, but to help bound/qualify it...

I'm talking about for a truck that might be driven at higher speeds in 4WD.  My only experience with this is on snowy highways, but high-speed desert driving is likely to be similar (but out of my experience).  For slow speed 'wheeling I think there are other acceptable / good options.

And while I would estimate that a TrueTrac would be acceptable in that situation, I don't have personal experience with it.  The physics behind it tell me that a TrueTrac would be worse than an open diff, but much better than the auto locker that I know is unacceptable.  So my estimation that it would be acceptable is mostly based off other people's testimonials.

Oh, and I think a selectable would be both more stable on the highway (unlocked) and more effective off-road (locked)

Jim - It leaks from both crank seals as well as the back of the intake.  And probably other places as well.

As for selling the 460, I'm going to use the short block and bolt on the heads from Huck, which have been fully gone through, and the EFI stuff from you.  But, I will be able to sell the L&L's, the Performer intake and carb, as well as whatever heads are on the engine now - although the thing is dropping one cylinder for sure and probably another so surely has valve problems.  And, for that matter, the D44 with Trutrac.

Bob - I don't envision high-speed desert driving, or even high speeds on snow for that matter as we no longer get enough to warrant that.  But, I do want the front to be driver-friendly as there's no telling who in my family will be driving it.  I grew up driving on snow and ice, and feel like I could handle the truck the way it is.  But no one else in the family has any experience whatsoever on slick roads, so it has to be friendly.  And selectable is my pref.  In fact, were it not for the Trutrac already being there in the rear I'd go that way back there.

On your point about spinning tires not having side traction, I remember all too well a friend of mine that was coming to work on a well-crowned city street.  The street was snow-packed and they stopped at a light.  When the light changed everyone else with their open diffs moved ahead, and his Nova with Posi slide sideways clear off the road.  So, open diffs with the option to lock them would be my favorite.  Wait!  That's what my 2015 has!  Pull the knob and it locks the rear up to maybe 10 MPH.  

I didn't realize that Big Blue's engine was in such bad shape.  
I'd thought that Vernon had put a lot of thought and work into it, but I note your comment to Shaun that there are only hack mechanics in FL.

Wheeler dealer!
If you do find a donor F-350 I'm sure there will be other bits you can sell to lessen the hit or turn a profit.
You have an great reputation among the community.  
I don't know anyone who would hesitate buying parts from you.

Oh, by the way...
Be aware that carb and efi 460's use different pistons.
So the straight up short block swap should be looked into.
The lower compression height or deeper pockets of a carbureted engine might not be optimal.
It's only a couple of points iirc, but the valve angles are off.

As Bill has recently built an efi engine for Darth I'd think he would be the go to for that information.

Thanks, Jim.  I will probably have parts to sell when the dust settles.

Yes, BB's engine has problems.  And, I was aware that the pistons are different, so do plan to check them out.  But, the engine has enough compression and/or ignition advance that it REQUIRES 92 octane to pull much of a load, and even then only w/o vacuum advance or it'll ping and then knock.

Here's sorta my game plan:

Pull the engine and run a leak-down check to see if the short-block is sound.  (Huck's 460 had up to 50% leakage in some cylinders and serious leakage in all.)

Pull the heads and determine what pistons I have as well as their deck height.

Calculate compression ratio and decide if that is going to work

Assuming it will, replace seals and install the pan and heads from Huck awa the valve covers and plenums from the F450

And, I'm sure to be back to y'all about what I find to get your advice on whether to proceed.

As for the truck to buy, with David's help I just bought a 1990 - 99 text section of the MPC in book format.    It should be in next Wednesday and then I can determine which of the 90's trucks have the right cross member.  And, of those I'll see which had a D60 front axle, which should then give me the list from which to go shopping.

I just had this conversation with Janey, so she knows what I'm doing and concurs with my plan of buying an F350 for the cross member awa front axle & suspension.  I explained that if ever there was a time, this is it.  So I might as well look for a truck that has all of the goodies rather than one with just the cross member.

So, we have a plan.  

I was only pointing out that efi heads have different angles and (I think) larger valves.

Check with Bill because I don't know for sure.

Yes, larger valves.  The heads I have, the F3TE's, have the largest of the 460 valves from what I remember.

I'll also have to compare chamber sizes on whatever is on the engine to those of the F3TE's.

But you are pointing out what I'd failed to think about - the possibility of the valve hitting the pistons.  Guess I'll be playing with play dough to find out.