Tranny swap, TCI c4 with 2500 Stall problems

interwest · 08-06-2009, 09:10 PM

So picked up a tci streetfighter c4 with a 2500 stall from a customer of mine for 600 bucks. Swapped the old one and put the new one in.

The problem is now that the 2-3 shift is crazy. It will switch between the two constantly looking for third. Looked under the car and found that the hose to vacuum modulator was broken so replaced it, and at first it shifted fine, but now it's doing it again.

Problem two. Trans fluid would bubble out of the dipstick onto the headers and smoke up really bad. Installed a seperate trans cooler to try to solve the problem. Well for a small time it did, but now it still smokes. Is the trans cooler supposed to be cool to the touch? I was thinking maybe the pump went out in the tranny, but any ideas?

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JMD · 08-07-2009, 12:18 AM

HMM...

Are you running the right fluid?

While it is normal to assume type F for a C4, many high perf rebuilds include modified clutches and bands that may require DEXTRON!

I imagine that the odds are better than even that this is the case with this TCI trans....

It sounds like the fluid is foaming up,,,, might be a result of the wrong fluid or if not it may improve with with a fluid change regardless.

The fluid on the hot exhaust can set your car on FIRE, GM had a problem with this in the 80s, I lost a chevy work van to this issue... burnt right to the ground. tranny fluid is a bitch to put out under a car...

Randys66gt · 08-07-2009, 10:44 AM

Almost right, TCI only recommends and uses Ford ATF fluid in all their trannys. Did you get the trans and converter separately and have to assemble? (Were they dry?) If you got them already assembled, change the fluid including the converter! When trans fluid gets hot and foamy, it will stay that way till changed. Use a big cooler and don't use cheap fluid. Auto trans fluid should be changed every 10-12K miles but 99% of the people do not think about it. Changing it at those intervals will ensure no foaming and a longer lasting automatic.

interwest · 08-07-2009, 11:17 AM

I just used Valvoline Type F. No the convertor and trans were together when I bought it. The guy I had bought it from, got deployed to Iraq and bought a T-5 when he got back and put around 1000 miles on the TCI c4 before his swap. So, try the TCI fluid maybe?

Yea it is all foamy. 1-2 shifts on the dime. At the track no issues. Coming home from the track it started foaming. Wierd.

fakesnakes · 08-07-2009, 11:23 AM

If it shifts, the pump is fine. Purge the fluid and replace it with Type F. That aerated fluid is ruined and will not return to normal.

interwest · 08-07-2009, 11:28 AM

I've drained it originally and put in Type F. Foamed up and replaced it with Type F and replaced the filter. So try draining again? Should I try a different fluid or is it something else causing the foaming?

JMD · 08-07-2009, 11:46 AM

The problem with changing fluid in auto trannys is that a lot (about 1/2) of the fluid will remain in the t/q etc even when the pan is dropped.

pro tranny shops will be able to purge the tranny....

I think something else is up besides the foaming though.... something is up with the 2-3 shift....

interwest · 08-07-2009, 11:59 AM

Well drove the car to work today. Shifted fine for 15 min or so (commute is around that long). Just about at work and then it started the same deal. Downshifts into 2nd with any pressure on the gas pedal and if I ease up it shifts to 3rd and just back and forth. Thanks guys for the help so far, I really do appreciate it.

Randys66gt · 08-07-2009, 12:39 PM

You NEED to drain the converter. There is a plug on it through the access plate in the front. The reason you are foaming is what you just told us, the trans is still running too hot. The best cooler I sold tons of is the 80266 B&M. Some people think that you can run a trans too cool but its not true. Get a trans temp gauge so you too can believe. Run regular trans fluid like Valvoline or Castrol. TCI still hasn't designed a better fluid.

cmanf · 08-07-2009, 12:56 PM

I had the same issue on a b&m c4 years ago in a falcon i had.
It was a new out of the crate trans with a 2800 stall.
Turned out there was trash clogging up the valve body. It had kind of a grease and clumpy metal wad in it.
Supershops where i bought it was no help then finaly I got a call back from B&M.

A week later a new valve body was shipped to me along with the fluid and pan gasket they dont know how or why it had trash in it but they took care of fixing it minus my time.
It had kind of a grease and clumpy metal wad in it.