School me on transmission options

[JimJam300]

The time is approaching when I will have to choose what to do with my SROD transmission and it’s sort of a difficult unit to find discussion on. Many expensive things hinge on my choice of transmission, and I don’t want to re-order carpet or something if I change it later. Any opinion I’ve been able to find has been on Mustang forums where the consensus is that it’s crap. Mind you I haven’t driven my Bronco more than 1 mile so I haven’t been able to form my own opinion, but mine leaks and will need work and I don’t know if it’s the right transmission for my needs. Knowing that it’s a transplant from a 351-equipped truck (code RUG-EE) tells me the original already died being powered by the lowly 300 inline six, and this may be the reason my Bronco has been off the road since 1996.

My needs are for long-distance cruising with fuel economy in mind and I’d also like having the option to tow a small trailer if I ever need to. I know the SROD is ideal for the former, but not the latter unless someone can prove otherwise. I also know that these needs scream ZF-5, but converting to a hydraulic clutch sounds like a lot of work and I’m a rather inexperienced mechanic. Cruising at 70mph on flat ground is very necessary for where I live, any slower and I’ve got big rigs trying to pass me. To give a comparison, I thought my 1990 Ranger 4.0 OHV with M5ODR1 trans and 3.73 gears on 31” tires was somewhat comfortable at a sustained 75mph getting 16-19mpg. My 300cid Bronco is 3.00 gears on 31” tires. Both have similar torque, 300cid makes peak much lower and has 50 less horsepower.

So as far as I know, my options are:

T-18/T-19, ZF-5, M5ODR2, modified Tremec T-5, or a modified “true” toploader (David Kee Toploaders start at $2400 which seems nice for a new unit). Any range I’m not satisfied with I could supplement with a gear splitter, but that’s another $2500 and more work. I’m not afraid to change out my gears either, I’m just about to remove the rear end and get it rebuilt anyhow.

[Rembrant]

I have the M5OD-R2 5spd in both trucks. The 84 is a 2wd and the 80 is a 4x4. I quite like the trans myself, but it seems most people want to heavier 3/4 ton ZF5 trans. Anyway, I can’t help with you decision much, but wanted to let you know that a hydraulic clutch swap is pretty easy. Don’t let that slow you down. It’s a little extra work and expense, but it’s not a big deal.

[Gary Lewis]

I agree that a hydraulic clutch swap is pretty easy. But I'd want to reinforce the firewall if I did it, although the small plate would be enough.

Big Blue had the T-19 when I got him, and I've had other trucks with the NP435, and I'm here to tell you that I don't like a tranny w/o an overdrive. I highly recommend an OD..

However, the ZF5 is a truck transmission. I don't know that I'd like it in a lighter truck than my F250. Yes, I had it in Dad's F150 and it worked fine, but it was old and needed rebuilding, so the syncros were shot. So I had it rebuilt and put it in Big Blue, and it is still a truck transmission and is slow to shift. If you try to hurry it you are going to hurt something, and they aren't cheap to rebuild.

I don't know for sure how an M5OD-R2 shifts, but what little I've heard is that it is a smooth tranny. And I believe they are up to pulling a small trailer. Plus, they may be less expensive to have rebuilt than a ZF5, which cost me $1000 several years ago.

 

[JimJam300]

I agree that a hydraulic clutch swap is pretty easy. But I'd want to reinforce the firewall if I did it, although the small plate would be enough.

Big Blue had the T-19 when I got him, and I've had other trucks with the NP435, and I'm here to tell you that I don't like a tranny w/o an overdrive. I highly recommend an OD..

However, the ZF5 is a truck transmission. I don't know that I'd like it in a lighter truck than my F250. Yes, I had it in Dad's F150 and it worked fine, but it was old and needed rebuilding, so the syncros were shot. So I had it rebuilt and put it in Big Blue, and it is still a truck transmission and is slow to shift. If you try to hurry it you are going to hurt something, and they aren't cheap to rebuild.

I don't know for sure how an M5OD-R2 shifts, but what little I've heard is that it is a smooth tranny. And I believe they are up to pulling a small trailer. Plus, they may be less expensive to have rebuilt than a ZF5, which cost me $1000 several years ago.

I liked the M5ODR1 in my Ranger. It was sloppy because the shifter bushings were shot the entire time I had it, but even in that state it felt much more precise than the SROD which feels like the ancient 4spd in my dad’s 1959 Austin-Healey (but worse because that car has a factory electronic overdrive).

[Gary Lewis]

I liked the M5ODR1 in my Ranger. It was sloppy because the shifter bushings were shot the entire time I had it, but even in that state it felt much more precise than the SROD which feels like the ancient 4spd in my dad’s 1959 Austin-Healey (but worse because that car has a factory electronic overdrive).

A Healy 3000? Boy, do I have a story about a transmission in one of those! But it is your thread, so...

[JimJam300]

A Healy 3000? Boy, do I have a story about a transmission in one of those! But it is your thread, so...

Next time I see my dad I can entertain him with your tale, so by all means.

His is a Healey 100-6, it was the in-between model of the 100 and 3000

[Gary Lewis]

A Healy 3000? Boy, do I have a story about a transmission in one of those! But it is your thread, so...

Next time I see my dad I can entertain him with your tale, so by all means.

His is a Healey 100-6, it was the in-between model of the 100 and 3000

Went to school at Kansas State and a buddy had a Healy 300. The tranny went out and he waited 6 months for the parts to come in from the UK. Finally he got his car back but the mechanic said he needed to break the synchros in by double-clutching. So he asked me what that was. I explained and he tossed me the keys and said "Show me." So we went for a ride.

At the end of the ride, as we came to a stop I double-clutched into first and he said "I would never have done THAT!" I asked why. "Because first isn't synchronized." I saw my life flash in front of my eyes. But, it had gone in w/o a snick of any kind, so I just smiled and tossed the keys back.

[Rembrant]

I don't know for sure how an M5OD-R2 shifts, but what little I've heard is that it is a smooth tranny. And I believe they are up to pulling a small trailer. Plus, they may be less expensive to have rebuilt than a ZF5, which cost me $1000 several years ago.

I liked the M5ODR1 in my Ranger. It was sloppy because the shifter bushings were shot the entire time I had it, but even in that state it felt much more precise than the SROD which feels like the ancient 4spd in my dad’s 1959 Austin-Healey (but worse because that car has a factory electronic overdrive).

The poor old M5OD-R2 gets a bit of a bad rap in internet dogma these days, and it's at least a bit unfounded in my opinion. People call them weak (and "junk"), but what nobody ever mentions is that they're usually referring to a transmission that is now 3 decades old, and often times with several hundred thousand miles on them. Ford pumped these transmissions out by the hundreds of thousands from 1988-onward, and for every guy you see complaining that they're junk, you'll read about another guy that put 300k miles on his and it is still working fine.

(Gary, I'll compare it to the old "Swiss Cheese" frames that everybody says are junk. They were perfectly fine in their day...but they might be junk after 40 Ohio or Michigan salty winters...lol).

One big advantage of the M5OD-R2 over the ZF-5 is going to be availability. From what I understand, the ZF-5 is especially hard to come by with the SBF bellhousing...and even harder when it's a 4x4.

I like how the M5OD shifts...it's definitely heavier/harder shifting than a car transmission, but lighter/easier than the ZF-5. I think the "tightness" of it compared to the old SROD is the fact it is top entry...no external linkages, etc like a typical top loading transmission. Replacement shifter bushing kits are cheap and easy to install.

My 2 cents worth;).

 

[ratdude747]

I don't know for sure how an M5OD-R2 shifts, but what little I've heard is that it is a smooth tranny. And I believe they are up to pulling a small trailer. Plus, they may be less expensive to have rebuilt than a ZF5, which cost me $1000 several years ago.

I liked the M5ODR1 in my Ranger. It was sloppy because the shifter bushings were shot the entire time I had it, but even in that state it felt much more precise than the SROD which feels like the ancient 4spd in my dad’s 1959 Austin-Healey (but worse because that car has a factory electronic overdrive).

The poor old M5OD-R2 gets a bit of a bad rap in internet dogma these days, and it's at least a bit unfounded in my opinion. People call them weak (and "junk"), but what nobody ever mentions is that they're usually referring to a transmission that is now 3 decades old, and often times with several hundred thousand miles on them. Ford pumped these transmissions out by the hundreds of thousands from 1988-onward, and for every guy you see complaining that they're junk, you'll read about another guy that put 300k miles on his and it is still working fine.

(Gary, I'll compare it to the old "Swiss Cheese" frames that everybody says are junk. They were perfectly fine in their day...but they might be junk after 40 Ohio or Michigan salty winters...lol).

One big advantage of the M5OD-R2 over the ZF-5 is going to be availability. From what I understand, the ZF-5 is especially hard to come by with the SBF bellhousing...and even harder when it's a 4x4.

I like how the M5OD shifts...it's definitely heavier/harder shifting than a car transmission, but lighter/easier than the ZF-5. I think the "tightness" of it compared to the old SROD is the fact it is top entry...no external linkages, etc like a typical top loading transmission. Replacement shifter bushing kits are cheap and easy to install.

My 2 cents worth;).

Nitpick: the M5OD is made by Mazda, not Ford.

[Gary Lewis]

Nitpick: the M5OD is made by Mazda, not Ford.

When someone says something is "junk" on Facebook I usually move on as I know s/he isn't to be believed. They say the same thing about the 351M's and 400's, which is not true. So it doesn't surprise me that they say that of the M5OD-R2. But if I were building a mild Bronco or F-150 I'd seriously consider that tranny. And I'd look for a rebuilt one.

On the other hand if I wanted a ZF I'd buy a rebuilt one with a warranty. And I'd buy from Midwest Transmissions. I've bought parts from them several times and they've always steered me right. And another guy on the forum bought one from them and it is working well.

On that page you will see that currently a small-block ZF5-42 4wd is $1367. But don't miss the $1000 core charge, which means if you don't have an old one to send in it'll cost that much. So you'll have to add the cost of a used tranny, and it gets expensive. However, I bought my ZF for $500, found that the syncros were bad and it sometimes wouldn't shift into reverse, which turned out to be a broken reverse gear. So added another $1000 in rebuilt and parts, and got no warranty. Which may be an issue as the 3rd gear syncro isn't very good, although it may be wearing in.