Thread: TCC lock up issues after rebuild and new TC

I had my trans rebuilt at a local trans shop, and decided to do some upgrades while i was there, a 3500 torque converter, and a zzp 4340 input shaft. Everything worked fine for 2 days then my tcc stopped locking up and it threw a p0741 code, so i talked to the shop and they said that they checked all the tcc solenoids, and valve bors and they were fine, and i checked the wireing and i didnt find anyhting. I heard that if you forget to install the oil diverter tube in the input shaft that it could case tcc lock up issues, what does this tube do anyway? And i was wondering if anyone knows if the zzp 4340 input shaft has one installed or do you need to swap your stock one?

Does anbody have any input

You know.. I am having the same problem.

I did a complete rebuild on my 04 GTP Comp G last May (2009), with ZZP 300M input, 2750 converter, new clutches, solenoids, 7/8th chain, transgo shift kit, etc.. lots of other bands/sun gears, blah.

Ever since, I have been getting P0741 and I get absolutely no lockup. I've had the car parked for a year now.. I even had the transmission removed from car and taken apart by another shop (on my dime) and was told nothing was wrong with it.

I have since replaced my brake switch (heard that can go bad), swapped PCMs, checked the 20pin harness for shorts, etc...

Still can't figure it out. I am borrowing a scanner AGAIN and having another guy take a look at it (avoiding going back to the shops since it's $110+ an hour with taxes).


I was going to try a "TAP" reset, since I know that should have been done, but I am unaware if the original guy did it. He won't help me out since he's blaming me for having a fault after he did the work (even though a complete rebuild should fix ANY error/code, which I didn't have prior to his work).
Let me know if you find a solution... I am completely fedup. I even bought a new ZZP converter after the original shop told me the ATI one I bought (new) was faulty. I don't know of anyone else who went to a 245mm converter having problems..

So far i have not figured it out, but the new solution i am trying is a new TC, the kevlar clutch in th ZZP TCC is not compatable with our TCC strategy. MY Trans guy said that kevlar clutch can be completely whiped out in 2 or three trips, so i am switching to a converter with a carbon fiber clutch to see if it will fix the problem. I'll keep you up dated, do you use a ZZP Converter?

When I had my stock converter before the rebuild, I had ZERO problems. Since I replaced so many parts, I have no idea what the culprit is. I then put an ATI street/track converter in, had the problem. Then bought a ZZP 245mm 2720 converter, same problem.

Starting to believe it's not the converters...

I was wondering if maybe the TransGo shift kit was put in wrong, or maybe something silly like an O-ring missing on the input shaft?!

Keep me posted!

A heads up... I did some driving around today with a MAC Mentor scanner (compared results under TCC Data with my '99 Bonneville SSEI, 4T65E-HD in there as well).

Well, everything looks similar, ISS speed, output speed, slip matches at acceleration, etc.

Only thing I can see that is actually different with the readouts is "TCC Release Press" is always on "YES". It never says "NO" like the other car when lockout is engaging.

So, I am now assuming I have a fluid/hydraulic leak somewhere.. BTW, I have an Overkill PCM w/ updated transmission parameters (modified). I am waiting for a 3rd PCM sometime this week that has stock transmission settings to use as a test to make sure it's not a modded PCM + upgraded transmission that's causing all my woes.

whan i had my car on a scanner everything looked good also except that the TCC duty cycle % was only 40% at its highest, and the reason for this is that the TAPs were never reset after the rebuild. And the extra high trans presures before the rebuild cause the pcm to back off the TCC duty cycle to soften the TCC engagement. when you reset the TAPs it puts the TCC% back to normal, but by this time the damage to a non carbon fiber TCC may already be severe enough to cause no lock up.

I had planned on doing a TAP reset, but I can't seem to figure out how to do it on this scanner. Have any suggestions?? Maybe the wording is different than I am expecting.

It's a Mac Mentor unit.. Pretty nice, but not sure how to fully use it.

Thanks for the heads up.. So, are you now having NO problems after the reset, or did I mis-read???

No it wasnt a fix but it might have contributed to the problem, the Tech2 and snapon scantools can do it. Most pepboys have a scanntool that can do it and they might not charge you if you know exactly what you want to do, if not the dealer can def do it.

I found the root cause of the problem, while my trans was apart today we found that the snapring that secures the drive sprocket to the input shaft had poped off causing the shaft to move back and forth wearing into the sleeve that the input shaft rides in, this caused low apply pressure to the TCC. The reason the snap ring poped off was the groove in the ZZP 4340 input shaft, that the ring rides in was machined incorectly it had a rounded upper lip causng it to pop off.

So your input shaft is no good? You are just going to replace it with another? You already have it back together with SUCCESS????

Curious, keep me posted. I was always wondering if my 300M input shaft was the culprit. I just got some gaskets from ZZP and they were wrong, so who knows if my input shaft was some race modified / no lockup version that I didn't ask for.

BLAH

I am going to replace it with another, but zzp is giving me a hard time about it being defective, i dont have time to send it out and wait for them to decide if its defective that could take weeks. You can see the difference in the edges were the snap rings sit the one on the left is the zzp and the right is stock.

Did you get your input shaft replaced by ZZP? I just brought my car to another shop, drove 4 1/2 hrs to get here. After taking it apart, apparently my 300M input shaft is missing a piece inside. I am being told it's a manufacturer's defect.. I emailed them last night to see if they will replace it, since I've had it for a year and a half on a car I haven't been able to drive/resolve. There was a member nearby who has let me use their input shaft (same one) in the meantime, but I need to replace it... Worried ZZP is going to stick me with buying another one. I decided to take this new revelation as a reason to inform them of the past half dozen products I've purchased that have almost blown my engine.. This was the final nail in the coffin, time to speak my mind!