C4 Rebuild or replace?

[Big Nick]

I recently acquired a '74 model with the 302 and C4 trans. I got the engine issues squared away and moved on to the transmission. Although the transmission
shifted OK, the fluid looked and smelled burnt. I dropped the pan and changed the filter, buttoned it up and replaced the ATF. That's it, didn't touch anything else.
Transmission now slips from 1st to 2nd and cold, will only shift into 3rd when (I assume) hits the governor. After that, shifts a bit early into 2nd with a momentary
slip and goes into 3rd OK. An old time mechanic friend told me that's not uncommon, sort of like the gunk was keeping the clutches working and new fluid made
everything slippery again. Changed the modulator and checked proper vacuum hose connections, no difference. My knowledge of A/T's is limited. (1) Is this something
that can be adjusted or do I need a transmission rebuild or exchange? (2) If it's the latter, can anyone recommend a shop in San Diego East county that is willing to
work on a 48 year old car's transmission?

 

[SteveL]

I would go for a rebuild rather than an exchange. I'd be concerned of getting a c-4 from something other than a bronco back from an exchange type of store ore shop. Then once yours is in the system it's gone

 

[gnpenning]

You didn't mention anything about your intended use.

Rebuild what you have, plenty of information for DIY.

When you changed the filter did you put the pin back in?

 

[Big Nick]

You didn't mention anything about your intended use.

Rebuild what you have, plenty of information for DIY.

When you changed the filter did you put the pin back in?

The spring loaded ball for pressure relief? Yes. If not that, did I possibly miss something? Intended use is realistically street and light offroad.
Yes, the more I learn, I need to hang on to the original transmission, ixnay on an exchange...

 

[Wes harden]

I need to do a c4 in a 74 E200 and have been looking around. Most shops don't have C4 to send you. They will rebuild yours. I think the C4 cases are getting rare.

 

[Rustytruck]

Have your C4 rebuilt there isnt a better transmission for the Bronco. if the fluid is burnt the tranny is wasted anyway so get it in the shop. add a tranny cooler if you don't have one. bad tire to gearing will cook a tranny so make sure your tire size and axle gearing match. 3.50 gearing up to 31" Tire, 4.11 for up to 33" tire, 456 for 35" tire. Your tranny will live a happy life with proper gearing. hope all the hard parts inside the trans are good. Bronco c4 have many Bronco modifications inside so you cant just swap it out with another one.

 

[fordguy]

I need to do a c4 in a 74 E200 and have been looking around. Most shops don't have C4 to send you. They will rebuild yours. I think the C4 cases are getting rare.

They are not rare, but they are getting harder to find. Rebuild what you have.

 

[mlaird]

Curious what you ended up doing with this. I just got quoted $3500 to rebuild my c4 in Texas which sounds crazy high to me.

 

[Rustytruck]

its not high if your replacing parts

 

[jamesroney]

Curious what you ended up doing with this. I just got quoted $3500 to rebuild my c4 in Texas which sounds crazy high to me.

A deluxe rebuild kit for a C4 costs $90.79 from Rock Auto and includes band, clutches, steels, bushings, filter and modulator.
The Standard kit is about $75.00
That means that if I were rebuilding a C4 in my Bronco, it would cost $75.00 plus fluid. It would also take me the better part of a weekend to do it. Of course, I would have done the build the instant it started misbehaving, and long before it cooked itself.

So yeah, $3500 is crazy high for a rebuild. If you are "replacing parts" then you are no longer doing a rebuild. You are into repair, and upgrade space. Anyone that puts high performance parts into a Bronco C4 deserves to be separated from their money. It's a really good transmission with over 10 years of factory improvements (1964+) Don't even get me started on shift kits...

Find someone that knows what they are doing, and get them to help you rebuild it. You will be glad you did.

 

[Viperwolf1]

A deluxe rebuild kit for a C4 costs $90.79 from Rock Auto and includes band, clutches, steels, bushings, filter and modulator.
The Standard kit is about $75.00
That means that if I were rebuilding a C4 in my Bronco, it would cost $75.00 plus fluid. It would also take me the better part of a weekend to do it. Of course, I would have done the build the instant it started misbehaving, and long before it cooked itself.

So yeah, $3500 is crazy high for a rebuild. If you are "replacing parts" then you are no longer doing a rebuild. You are into repair, and upgrade space. Anyone that puts high performance parts into a Bronco C4 deserves to be separated from their money. It's a really good transmission with over 10 years of factory improvements (1964+) Don't even get me started on shift kits...

Find someone that knows what they are doing, and get them to help you rebuild it. You will be glad you did.

Why even buy the $90 kit if you're not going to replace anything. The old gaskets and seals and clutches and bands worked fine for decades. No sense in swapping them out now and it would bump you into the "repair" category.

 

[Hammer6672]

I Had one bench built for 500.00 in GA. Last year

 

[Wes harden]

@mlaird give these guys a call https://www.phoenixtrans.com/ one of the people here, if not the owner is an old car guy, Blazer, but nobody is perfect. They will have to rebuild yours, they don't have a ready to go in inventory.

 

[pcf_mark]

The basic question - "C4 rebuild or replace" I would answer with rebuild. These are simple units and the parts are readily available. If you get the DVD from BadShoeProductions, the parts list from ViperWolf then take your time and work clean this is a job any handy person can manage. Easily the most difficult part of the job is taking it out and putting it back in.

My only other piece of advice - get a rebuilt torque converter too. For $99 - $129 it's worth it.