BigD

iTrader: (31)

I just got done rebuilding my trans (4L60E) by myself. Everything works great, except I don't have torque converter lock-up. I checked the TCC valve in the pump, replaced the electronics. It has a Transgo reprogramming kit in it, made sure all the mods were done correctly to the valve body. I'm sure the o-ring is on the input shaft too. No codes. engine or trans. It locked-up once after a short squirt on the throttle, hasn't since then. What else could it be?? Any help appreciated.

Pete2k_Z28

Did you remember to put the O-ring back on the input shaft after the pump was installed?

TeamTripp

What year unit is this and how far does the TCC lockup valve in the pump move? Many of the '97 and later PWM pumps had a plastic checkvalve behind the apply orifice that would break and get jammed into the valve. The valve would move, but not all the way. It needs to rest on the plate against the snap-ring. If you push on it, it should go about .500" (half inch).

Which TCC valve did the TransGo kit come with? Was it a long valve with a blue spring, or a short valve with many "grooves" in it?

BigD

iTrader: (31)

Positive the o-ring is on the input shaft.

It is a 98 PWM pump. I took the TCC valve in the pump apart 2 times after I got it running to double check the springs and make sure valve was installed correctly, it was. Don't recall seeing a plastic check valve, unless it is a yellow screen looking thing? If so, I replaced it. It also had a steel checkball and spring in another passage held with a pin? My transgo kit came with the long valve with blue spring. It moved freely in the valve body FWIW. I am at the point of pulling the trans and making sure the check valve in the input shaft isn't jammed.

Sport Truck

Mine did and is doing the same thing, put it together and it went thru the gears perfect, and then locked up the converter. Now it seems that the lock up happens at the same time 4th gear shifts. no codes or anything out of the norm, it also has new everything in it as well as a trans go kit in it. 55mph shift it out of o drive into 3rd and it down shifts ok, go 55-60 mph and hit the tow/haul botton and it is ever so slight in difference.

BigD

iTrader: (31)

Ok, pulled the trans back out. Couldn't find anything visually wrong in the pump or on the input shaft as far as seals go. The TCC valve is free, can push the valve .500" farther in the bore when it is assembled. Is there anything else I could be missing? What is left the valve body?

Also, as far as stator support seals go, which is better? teflon or the scarf cut? Does it really matter? Trans had the scarf seals in it when I disassembled it (TCI trans). I know the stock ones were teflon. Hate to by a teflon seal installer and sizer if not really necessary. TIA

Darrin

BigD

iTrader: (31)

Figured it out! Wasn't mechanical at all. Was the misfire detection thing in the PCM. This will explain it https://ls1tech.com/forums/pcm-diagnostics-tuning/162767-i-just-replaced-my-torque-converter-now-unlocks-randomly-fix.html Thanks Ryan!

I found it by clearing the codes, even though there were none. It would lock up once then never again. I then cleared the none existing codes again and it worked only once again. From that point I knew it was electrical. Evidently I haven't had lock-up for awhile, just never noticed it.

Thanks everyone for your help.

Darrin

Roadrunner 45

iTrader: (1)

big D- do you do trans rebuilds for a living? If not how'd you learn how to do it? I ask cause I just fragged my trans again, and I'm sick of waiting to get the damn thing back (last time was 6 weeks and the thing was never right when I did get it back).

I want to learn how to do it so I dont' have to count on anyone else in the future.

BigD

iTrader: (31)

Nope, first trans. I ever rebuilt. Bought an ATSG manual and the proper trans. tools and did alot of reading. Intimidating at first, but it wasn't to bad in hind sight. Couple hundred miles already and all is still good. If I was in your shoes I would set-up to a TH400. Call me at work if you need more info, I work up the street from you!

Darrin