As a daily driver, my new straight 6 with - what I assume now is 3:50 gears, is really wanting an overdrive for the freeway. 70mph in 4th gear is just sounding like she is running hard core.

I found a nice, rebuilt, freshend up T-5 out of a stang for a good price. I used to race with this tranny back in the day. The guy wants 300 for it.
Does anyone know what else would have to be swapped/changed in order to use a T-5 in my 79 4x4 300?
I'm sure there are others out there who has done this. Or maybe I should search for a rebuilt borge? tremmic?
Thanks for the help!

 

The T5 would need an adapter plate to bolt up, but won't bolt up to your transfer case.

A ZF or Mazda box out of a 4x4 is the way to go.

 

Yeah, a ZF is the way to go. It is super stout, has a granny first, and a nice OD, and it will bolt right to you block. Get one off a 351. I have one sitting in my garage for my truck. There are many threads about the install. Just google it or search here on this forum. You'll need a hydraulic clutch, and to shorten, lengthen your d.shafts too.

I think you'd fry that other trans in a truck. Good luck.

 

Thanks. I will search on this. Guess I was just thinking that I was putting down 500hp on my T5 and she was always fine. and the cost was good.
But I will seek out this ZF thing and see, I'm sure there are tons of threads on it fo sho.

 

Ford ZF 5 Speed Transmission
ey?

 

Heya,

Sounds like a fun project.

That one you posted won't work. You need one that's from behind a 300 or a 351. (Not that they won't fit behind a 302, but 302s didn't come in F250s and above, which is what the ZF was in).

That one is from a diesel and won't work in any way.

Check out Jalopy Jungle out in Nampa. I've seen some out there. You'd have to pull the transmission yourself, but it would also give you access to all the extras, like the pedals, master cylinder, hydraulics, etc.

 

Ah ok . Yeah we need to hit the barters and JJ. Maybe take someone with me that knows how to drop a tranny quick. Other bits I need too anyways.
Thanks man, ill look around

 

It's been a while since I've been out there, but my list is getting longer, so I need to. It's fun to wander around those old trucks and Broncos. Can be like a kid in a candy store sometimes.

 

ah man for sure. The lady and I want to go hit those, it has been years.
With 3 of us we could make a more efficient getaway. We work in Nampa and can come and go as we please. I have my list for my 79 and she has a list for her 73 beetle.
should be nice this week eh!?

 

I may have to come over to Nampa. Towed a freind's old car to the Jalopy Jungle in Twin Falls and was looking over the Fords while he was doing paperwork. They were mostly 4x4 (I have a 4x2 of course) and nearly all ATs. I just want a M5OD core to rebuild so I can swap out the one in my truck. The only 2WD MT they ha was on a Bullnose and was a 4sp. Couldn't tell which one it was though and it was still connected to the engine, so no was I was going to get it out of there.

Oh and forget about ZFs there (even then, I think I would need a new driveshaft anyway due to the casing length differences.

I'll stick with the M5ofDeath. With my 3.55 rears, it pulls okay from a stop (it is a little tricky right at GVWR, and it's really not good to go over GVWR). My current one simple has no 1-2 synchro and not much of a 2-3 one, please the bearings are starting to complain. That said, I think if I do the rebuild myself and make sire the rail plugs are replaced, it should be fine (thankfully the clutch and slave cylinder were replaced by the PO and are going strong)

 

Don't know how hard you plan on running your truck, but a street driven 4x4 would also do well with a M5R2 Mazda designed box. It doesn't have a grannie first gear (which for my street driven 2wd works great as the Grannie was useless to me). they're cheaper and easier to find than the ZF boxes and an easy swap. You do need a hydraulic clutch unit though which your '79 might not have.

TR

 

I finally found a sb ZF from a forum member. You might want to place a wanted ad in that section of the forum. Now I am rounding up parts and trying to figure out how to do the clutch master rod connection, and how to attach the speedo cable. It would be nice to delete all the Ford gauges and convert to all new Quality ones, but my banker has no imagination.

The good thing is I'm not far from the drive line specialist to make the new drive shaft. It is an expensive swap.

I'm struggling with throwing it in as is and not having it rebuilt. It is untried. I found a guy to rebuild it for $375 labor. The kit runs about $200 with syncros, bearings, seals, etc. Then there is the clutch.

With a 3:31 rear and oem size tires, can someone tell me how many rpm I will be turning at 65 in overdrive? With my formula it seems to be 1772 rpm @ 65mph? With 31 inch tires. Is that the correct tire size for oem?

 

Another question? I read mention of a clutch sbf (solid mass flywheel) clutch. They seemed to be describing the manufacturer. I can't find it. Does anyone know anything about this? Thx.

 

I think that is for the diesels, they replace the dual mass flywheels that had some issue. I believe any standard 4.9 flywheel will work with the ZF.

 

A ZF will need a hydraulic clutch too. If you are running 4x4, the lack of a granny gear can somewhat be compensated by using low range if you need to slowly drag something. That said, my M5)D with 3.55 rear and an open Diff yanked a couple of 10ft tall juniper bush/tree things out of the ground pretty easily and seems to have no problem towing 6000 or so lbs. Reverse is still geared way too high, but that's not an issue for me.

The biggest problems with the Mazda box are due to the shift rail plugs falling out, draining the oil and cooking the bearings and clutch slave cylinder leaks (also can be an issue with a ZF as both use a concentric slave cylinder). Sadly, people didn't take the time to fix issues, so eventually a dry M5OD will self destruct. I keep a close eye on the tranny fluid level in mine as I haven't checked the shift rail plugs. At some point it must have gone dry because the bearings are pretty noisy in everything but 4th gear (direct drive).

The other waek pint of the M5OD s the synchros. The same box was used in the old Thunderbird SC and synchro issues really dog those boxes. The M5OD simply can't be power shifted; the shifter needs a good pause for the synchros to spin up right. My 1-2 synchros is all but gone and the 2-3 crunches if I don't give a nice pause between gears. If I pause between gears and rev match, 1-2 is no problem and 2-3 just needs a little pause. People who powershift these boxes tend to end up forcing the shift forks, wearing them out or breaking them.

So why would you want a tranny that potentially has the above issues? If you keep an abused one full of fluid and shift carefully, it'l still run fine and haul a heavy load. Since the OP wants to swap out tranny, the M5OD is a great match because he synchro and bearing rebuild kit is only about $200 and it is said to be possible the easiest 5sp gearbox to rebuild. As long as you have the space to lay everything out and some basic tools (I'm not sure that there are any specialty tools requires based on my research), you can easily rebuild a box yourself. Replace the shift rail plugs with metal plugs (they come in a lot of the rebuild kits now) and it should be good for regular truck duty. I wouldn't but it behind a highly modified motor and certainly wouldn't try and tow 10000+ lbs, so it is a 1/2 ton transmission.

I am nursing mine along for another year or 2 until I can budget the tranny rebuild.