C4 Transmission - Rebuild or Replace?!

[Uncle Butter]

Hello again! I'm looking for some advice on my new-to-me '72 Bronco; this time with the C4 transmission.

If you saw my last thread, you'll remember I just recently picked this bad boy up from a builder in Sonora. Among other things, he said this transmission was "fresh rebuilt automatic transmission". However, it's leaking profusely from multiple places and you can't even get it to shift into third gear. The shop I had it inspected at says it needs to be rebuilt. This is also the 2nd opinion from a reputable shop so something is definitely wrong.

Down to the brass tax: do I rebuild it or replace it? If I replace it, what do I replace it with? It has a 351 Windsor in it.

Help!

 

[fordguy]

Gearing, tire size and intended use?

 

[SteveL]

Like fordguy says. If its gonna be a dd with a good amount of freeway use it might be worth going with an od. If it's just a weekend ride or just cruising town doubt it's worth the extra expense. I'm going thru it on the 72. Being it's not a dd I'm just going with a c-4 since it's a direct bolt in. Less extra parts to buy like driveshafts and mounts. Also depending on what nonstock tranny you choose may have exhaust clearance issues too.

 

[Uncle Butter]

I don't know anything about gearing yet, but I'll drive it on road about 90% of the time and light off road about 10% of the time. Mostly fire roads in the mountains, easy desert trails, not any rock crawling or the like. Tires are 35" x 12.5".

 

[Uncle Butter]

And yes, some freeway use getting to different towns...

 

[jckkys]

My C4 was a great trans for the 43 yrs. I owned it and drove it to work daily. It's still a great trans. I've gone cross country 4 times and it served well on the interstates. EBs are just not 80 MPH cruisers. But at 65 things work well on the highway.

 

[74 Bronco Billy]

1. "Builder in Sonora" gave you an interesting rebuilt C4
2. Easiest fix and cheapest is rebuild C4 with top quality parts. They can handle 400 hp with right technician/ mechanic
3. What other problems are going to raise their ugly head from this builder? Have a great mechanic that knows Broncos go through it so you eliminate those potential problems. This will eliminate them, then give you the chance to see if the over drive tanky is in your budget.
Good luck

Sent from my SM-G955U using Tapatalk

 

[spap]

Have you gone back to the builder
He had it bolt ask by who, prob no help but a least you could let other people know to avoid the problem.

 

[tatersalad]

I love my C4 . It has served me well for 20 plus years of 90/10 driving running 33 12.50 and they're cheap to rebuild.

 

[Rustytruck]

does the dipstick tube screw into the passengers side of the transmission pan? if so rebuild it. Bronco C-4 was the best of the bunch so replacing it with another is not really a good option. send some pictures.

 

[jmangi62]

Hello again! I'm looking for some advice on my new-to-me '72 Bronco; this time with the C4 transmission.

If you saw my last thread, you'll remember I just recently picked this bad boy up from a builder in Sonora. Among other things, he said this transmission was "fresh rebuilt automatic transmission". However, it's leaking profusely from multiple places and you can't even get it to shift into third gear. The shop I had it inspected at says it needs to be rebuilt. This is also the 2nd opinion from a reputable shop so something is definitely wrong.

Down to the brass tax: do I rebuild it or replace it? If I replace it, what do I replace it with? It has a 351 Windsor in it.

Help!

You replace it, and sell it to me.;D

 

[Uncle Butter]

Thanks for the great advice. @74 Bronco Billy: Yes, I've contacted the "builder" and he says it's absolutely been rebuilt recently and says both opinions are wrong. The problem is that it's leaking profusely in several places so my trust is waning to put it lightly. I'll post pics of it when I get it back from the service tech. @Rustytruck: The dipstick tube is actually welded into the transmission pan on the passenger side. I'm pretty sure that is not normal.

 

[Huckit36]

The driving you describing would make me think to rebuild what you have. I love mine, crawls really well and can still run up the 101 at 70. I'm considering replacing it to get the gearing down lower. There's a guy near Sac that does rebuilds, did a good job and had a good warranty for a friend of mine. I can see if I still have his email if you want. Another buddy bought a ’72 and put an aod from summit in. But 100% road driving that one. But it's a good option.

 

[Uncle Butter]

@Huckit36 I would love any references you have and would greatly appreciate it. At minimum to get their opinion and at most to have them rebuild it.

 

[Huckit36]

PM sent. Hope it helps.

 

[Uncle Butter]

Received. Thanks again. I'll reach out to him if need be.

 

[welndmn]

Rebuilding a C4 is about one of the cheapest rebuilds out there, if you pay someone to pull it and rebuild it, I'd expect it to be about 1k.

To play the other angle too, just cause it's rebuilt does not mean it can't leak. Stuff happens and some times brand new parts are bad and leak.
If you pay someone to fix the leaks, there is a good chance they will be able to tell you if it was rebuilt or not once they open it up.