I read in another post that you can get an aftermarket TCC apply valve with a teflon seal and this may help out low rpm dead spots or shudders in the torque converter when in o/drive. Such as when in o/drive at 45 to 60 mph in lock up (I have 273's). To be honest I do not even know what the heck this TCC valve is but if getting one helps me out then:

Does anyone know more about this aftermarket TCC apply valve with the teflon seal, where can you get it, do you have a part number and how much? Is it hard to change as in can you get to it without ripping too much tranny guts out??

68SSElCamino was the one who mentioned this in the other post.

Anyone??

 

The best place to get this part is through Sonnax industries. The web site to start on is www.Sonnax.com and the part # is one of two.
For PWM application order the 77805E-K
for non PWM theory use 77805-K

This is for the TCC apply valve located in the front pump of the transmission. The OE valve wears the bore and this causes the fluid to bypass and kick the valve into a neutral position.

For the harsh 1-2, you want to address the TCC regulator valve located in the valve body.
This can be done with another Sonnax part #.

I would need to know application and year to advise on the correction for this problem, but its a matter of removing the valve body and reaming the bore. Once this is done you use a anodized aluminum valve with a wear resistant sleeve to prevent the side loading and wear thats caused by the OE valve.

This is NOT a job for the inexperienced! Better to take it to a shop and have the problem corrected, then it would be to have the shop correct the problem you could cause attemting to correct the problem......... (say that 10 times fast) :-Þ

 

Ive had this problem in my 97 Z for years. Every once in a while it throws a P1870 code and starts the harsh 1-2 shifts untill you shut the car off. Then its fine untill it happens a few days later.
Ive been just living with it and dont realy mind it anymore but would like to find a solution.
GM claims installing the revised valve body fixes this problem. You can get this valve body for $275 from gmpartsdirect.
But ive heard of guys replacing the valve body and still having the problem.
If this in fact was the problem, wouldnt I feel the transmission slip or something. Because ive never had a bad shift in it.
I would just like to stop the P1870 code from comming on. If anybody knows how to do this, let us know. Brian at pcmforless said he could not.
I beleive this is a software calibration problem. Something is telling the pcm the transmission is slipping but in fact its not. If anyone knows how that works, please enlighten us.

 

VegasZ:
The harsh 1-2 shift is most often in the valve body. The TCC regulater valve bore gets oversized on one side due to side loading. The replacement valve uses a sleeve to restore the bore and this sleeve keeps the valve centered to prevent future wear.

The valve body can be fixed for less money then you would spend to buy a new one that will eventully have the same problem.

Fix this and be done. The worn valve is sending faulse readings to the computer, but its also sending signal to the converter apply that will kill the converter.... First the lock up friction, then the piston and apply surface. A sure sign of this will be a blue ring (caused by heat) on the front side of the converter near the mounting area (flex plate side).

The 4L60E has been through many revisions in its life. While its a great transmission in general, it has inherant problems.
Once called the 7004r (84-93) this transmission made many shops a lot of money.... 93-96 it was the 4L60 and is now the 4L60E that most of you run.

 

Thanks for the reply. Your knowledge will be well appreciated on this board. Ive heard of this fix before. It makes sense and I may just go ahead and do it.
I know I can take the valve body out myself. I just need to find a place I can trust to sleeve it.