[mike 96 ws6]

I did very little searching since I'm in a bit of a hurry, {need to get parts ordered} but found no results for 'isolator valve'.
I'm trying to get all the parts together to rebuild my 4l60e in my 96 trans am this weekend. I have a TCI #378950 rebuild kit. A short tech info sheet that came with the TCI kit mentions a Sonnax kit and reamer available that includes an isolator valve, sleeve and regulator valve. It is intended to correct PWM boost and actuator feed oil loss and correct for slip code on 93-97 units.
Since I'm going to be using a 3000+ stall converter with an OBD1 {conversion} PCM, will this kit eliminate the problems that are common with using a high stall speed converter with OBD1? If so, has anyone got a part # or link to where I can order it?
Also my rebuild kit does not include vanes for the pump. I have only built non-electronic trannys and not familiar with the 4l60e. Shouldn't I be replacing these vanes while I'm in there?
Do I need to order a 0.490 boost valve? Beast sun shell?
This car sees daily driving around town with little highway use and 20+ 1/4 mile runs yearly. Dyno #'s are around 280 rwhp/ 305 rwtq now but a cam, heads and n2o will be added soon so I'd like to build the tranny pretty strong now although the $'s are getting low. I can come up with $300 or so more.
Are there any other parts I need to get ordered?
TIA,
Mike

[Crosley]

One of the parts you are worried about is the valve assembly for the PWM lock up circuit. TransGo has a valve that slides in and fixes the problem. No need for the reamer and the related expense, IMHO.

The actuator feed limit valve is a different area. It is behind the force motor where the main line pressure is controlled. I've never had much problem with this valve asembly.

edit: the problem with a high stall speed converter is the OE programing for the PCM.... When it sees RPM's and related items outside the parameters of the program . It then sets a hard trouble code , which turns on the service soon light.

I believe you have custom programing if I remember correctly

[mike 96 ws6]

Originally Posted by Crosley

One of the parts you are worried about is the valve assembly for the PWM lock up circuit. TransGo has a valve that slides in and fixes the problem. No need for the reamer and the related expense, IMHO.

The only valve I have ordered for the pump is a .049 reverse boost valve and sleeve. I'm driving to TCI in Ashland Ms {25 miles from me} in the morning to pick-up a new converter and I'll see if they have the valve for the PWM lock up circuit {is that the tcc apply valve in the pump?}. I don't know of a TransGo supplier locally and I won't have time to order it online and delivered by this weekend.

The actuator feed limit valve is a different area. It is behind the force motor where the main line pressure is controlled. I've never had much problem with this valve asembly.

Then I'll leave that alone.

edit: the problem with a high stall speed converter is the OE programing for the PCM.... When it sees RPM's and related items outside the parameters of the program . It then sets a hard trouble code , which turns on the service soon light.

I believe you have custom programing if I remember correctly

Yes I have LT1 Edit programming software but I don't know what needs to be changed for this. Since the valve I was hoping would address this problem won't, I'm going to have a mail order tuner that I have purchashed programs from before send me a program to flash that supposedly will fix this stall-vs-PCM problem. I hoped I could save that money.
BTW: I also have a 'Beast sunshell' {SPX Filtran} ordered since this part was broken in the 700r4 I dissasembled a few weeks ago. I've since read several post about it being a weak OEM part in the 700r4, 4l60 and 4l60e's.
The converter I'm getting from TCI tommorrow is a 10" with a 12" clutch, approx. 3000-3400 stall with SBC. {part# 243106}. Do you have any opinion on this converter? It's about all I can afford right now {$576}.
Is there any other parts I need to get tommorrow?
Thanks a ton for your help!

[Crosley]

Nope.... the PWM valve assembly in the v-body is the problem area. Wears out the bore. TransGo orange box kit fixes this.

if you have a SERV v-body , then TransGo has another replacement valve since GM oversizes the valve bore for the PWM assembly

{is that the tcc apply valve in the pump?}.

[mike 96 ws6]

Originally Posted by Crosley

Nope.... the PWM valve assembly in the v-body is the problem area. Wears out the bore. TransGo orange box kit fixes this.

if you have a SERV v-body , then TransGo has another replacement valve since GM oversizes the valve bore for the PWM assembly

Okay. I got the part # T74165E from the the other thread on this topic from 5-15-05. I'll try to find one in Memphis tommorrow.
Thanks

[mike 96 ws6]

As usual I did not have everthing for the rebuild this weekend but I got everything apart and see what I need. The TCI rebuild kit I got was not correct, marked "not for moulded pistons". The seals for the overun, foward and 3rd-4th pistons are for the earlier style like in the 700r4 I tore down a while back. My 96 4l60e has these seals moulded onto the piston, therefore a replacement of the piston is required. I'll order them from the dealer in the morning. What year did they start using the molded pistons? My rebuild kit application list 96.

Questions:
The ATSG manual says the ball {in side the ball capsule module} in the end of the input shaft can be taken out for firmer TCC apply. Is this correct?

ATSG also says the 3-4 accumulator spring can be left out for firmer 3-4 shifts. Is this correct?

Do all 7 check balls need to be re-installed on the bottom side of the valve body separator plate? The reason I ask is because when building TH350's, I would install 'only' the check ball closest to the modulator valve. Just wandering.
Thanks again.

[Crosley]

install all the check balls, cept the one near the 3-4 accumilator piston in the main case.

4L60E tranys respond very different to opening the shift holes in the plate. On a t-350 or 400 it is common to leave the check balls out for firmer shifts.

a 4L60E or 65E will shift very violent with checks balls left out say on the 1-2 shift .

If you have a vette or billet servo for 2nd gear , you can clean up the 2-3 shift with a coasting band servo spring from a t-400. It pushes the 2nd gear of the 4L60 servo off slightly faster

Install the 3-4 spring into the case first then the accumilator piston. You can also drive a 1/4 inch check ball into the feed hole at the bottom of the hole in the case where the 3-4 piston moves.

if the molded piston seal is soft , reuse it

the check ball in the input shaft end will firm up the tcc apply a bit if you also install the TransGo valve in the PWM circuit. With your custom programming I guess the PWM programming is gone. PWM lock up style is to soften the apply and actually slip the converter clutch.

Originally Posted by mike 96 ws6

As usual I did not have everthing for the rebuild this weekend but I got everything apart and see what I need. The TCI rebuild kit I got was not correct, marked "not for moulded pistons". The seals for the overun, foward and 3rd-4th pistons are for the earlier style like in the 700r4 I tore down a while back. My 96 4l60e has these seals moulded onto the piston, therefore a replacement of the piston is required. I'll order them from the dealer in the morning. What year did they start using the molded pistons? My rebuild kit application list 96.

Questions:
The ATSG manual says the ball {in side the ball capsule module} in the end of the input shaft can be taken out for firmer TCC apply. Is this correct?

ATSG also says the 3-4 accumulator spring can be left out for firmer 3-4 shifts. Is this correct?

Do all 7 check balls need to be re-installed on the bottom side of the valve body separator plate? The reason I ask is because when building TH350's, I would install 'only' the check ball closest to the modulator valve. Just wandering.
Thanks again.

[mike 96 ws6]

Originally Posted by Crosley

install all the check balls, cept the one near the 3-4 accumilator piston in the main case.

That would be the one on top of the plate-
#91 on this page.
Why does it say no 10? Is that a different size than the rest {.250 = 1/4"}?

[QUOTE]If you have a vette or billet servo for 2nd gear , you can clean up the 2-3 shift with a coasting band servo spring from a t-400. It pushes the 2nd gear of the 4L60 servo off slightly faster[QUOTE]
I have a vette servo. Do you happen to have a part # for the TH400 spring. I don't have access to part #'s for TH400 or a TH400 tranny laying around. I'll order one tommorrow at the dealer.

Install the 3-4 spring into the case first then the accumilator piston.

That's reverse of how it is assembled from the factory, correct?

You can also drive a 1/4 inch check ball into the feed hole at the bottom of the hole in the case where the 3-4 piston moves.

With a hammer and punch? Will it stay there?

if the molded piston seal is soft , reuse it

I need one new piston since this piston has a chunk out of it. Id rather go ahead and get all three moulded type pistons new while I've got it apart.

the check ball in the input shaft end will firm up the tcc apply a bit if you also install the TransGo valve in the PWM circuit. With your custom programming I guess the PWM programming is gone. PWM lock up style is to soften the apply and actually slip the converter clutch.

I'm going to install that Transgo valve #T74165E so I'll leave the checkball out. The TCC apply tables in the PCM are still as they were from the factory except for TCC apply vs %TPS in MPH, TCC release vs TPS% in MPH, and TCC shift delay. I'll run the this program until I see a need to change it.

What do you think about the dual coolers shown in my photo album ? If I have a tranny failure, it should not be heat related.

I have to work at my real job all week so I plan to re-assemble everything next Friday.
Thanks again for your help.

[Crosley]

Originally Posted by mike 96 ws6

That would be the one on top of the plate-
#91 on this page.
Why does it say no 10? Is that a different size than the rest {.250 = 1/4"}?

======= that is the check ball. size is not different. I cannot answer the question about the ATSG manual , I don't own one on the 700/4L60 trannys


[QUOTE]If you have a vette or billet servo for 2nd gear , you can clean up the 2-3 shift with a coasting band servo spring from a t-400. It pushes the 2nd gear of the 4L60 servo off slightly faster

I have a vette servo. Do you happen to have a part # for the TH400 spring. I don't have access to part #'s for TH400 or a TH400 tranny laying around. I'll order one tommorrow at the dealer.

====== I do not have the number in front of me

That's reverse of how it is assembled from the factory, correct?

========yep

With a hammer and punch? Will it stay there?

======== I've done it that way for decades

I need one new piston since this piston has a chunk out of it. Id rather go ahead and get all three moulded type pistons new while I've got it apart.


I'm going to install that Transgo valve #T74165E so I'll leave the checkball out. The TCC apply tables in the PCM are still as they were from the factory except for TCC apply vs %TPS in MPH, TCC release vs TPS% in MPH, and TCC shift delay. I'll run the this program until I see a need to change it.

What do you think about the dual coolers shown in my photo album ? If I have a tranny failure, it should not be heat related.

I have to work at my real job all week so I plan to re-assemble everything next Friday.
Thanks again for your help.

======= keeping tranny oil cool is important

[mike 96 ws6]

I worked all night 11-7 then went to Memphis to get the transgo kit, so I'm going to take a nap and get started this evening.

I've got a couple more questions:

The Transgo kit has the iso-conv valve in it along with several other items. Should I only install the iso conv valve according to the directions and leave the rest alone? By looking at all the directions, I may need to just install the shift kit stuff I got in the TCI rebuild kit to keep from messing something up. Would it be better to go ahead and do the transgo?

ATSG recommends removing and discarding these load release springs but as you can see, Transgo says they are needed. What do you say Crosley?
Thanks again,
Mike

[Crosley]

do not mix the kits together with your limited experience.

instal the Transgo PWM valve & you are done with the PWM problems. The bore wears out, the valve fixes the pressure loss for lock up.

Load release springs depends on the 3-4 clutch pack you are installing

Originally Posted by mike 96 ws6

I worked all night 11-7 then went to Memphis to get the transgo kit, so I'm going to take a nap and get started this evening.

I've got a couple more questions:

The Transgo kit has the iso-conv valve in it along with several other items. Should I only install the iso conv valve according to the directions and leave the rest alone? By looking at all the directions, I may need to just install the shift kit stuff I got in the TCI rebuild kit to keep from messing something up. Would it be better to go ahead and do the transgo?

ATSG recommends removing and discarding these load release springs but as you can see, Transgo says they are needed. What do you say Crosley?
Thanks again,
Mike

[mike 96 ws6]

Originally Posted by Crosley

do not mix the kits together with your limited experience.

instal the Transgo PWM valve & you are done with the PWM problems. The bore wears out, the valve fixes the pressure loss for lock up.

OK, I'll leave the other Trango stuff alone.

Load release springs depends on the 3-4 clutch pack you are installing

It says they must be used with original thickness bottom and top pressure plate and snap ring which is what I have so I'll keep them in there.
Thanks,
Now for that nap.

[Crosley]

RE: the release springs,

grind down the metal retainer the springs fit into. Take about .040 to .060 off the end where the spring extends beyond the retainer. This allows for more compression on the clutch pack.

Check the clearance of the 3-4 clutch pack and these release springs so the release spring retainer does not foul up the pressure plates of the clutch pack. the pack will slip if the retainer binds up the works

I hope that is clear.......

Originally Posted by mike 96 ws6

OK, I'll leave the other Trango stuff alone.


It says they must be used with original thickness bottom and top pressure plate and snap ring which is what I have so I'll keep them in there.
Thanks,
Now for that nap.

[mike 96 ws6]

I got it all back together today. I won't know how strong it is till after I drive it a few days to break in all the new parts and change the fluid / filter. I may need to pull the 1-2 accumulator back out and cushion that shift a little more.
Thanks very much for your help Crosley. I posted on a couple of other boards but got little help. I usually post on ws6zxr.com under username 'lectrocrew' and linked this thread in a thread I started there, in case others have similar questions. .
Thanks again.

[mike 96 ws6]

I have a couple of issues. 2-3 shift at part throttle is quick then it seems like the 2-4 band is still holding momentarily. What should I do? Should I install a stiffer servo return spring or modify the oil passage in the servo bore?

Also I'm still having a problem with the TCC holding. The ATSG manual suggested leaving out the ball inside the capsule in the end of the turbine shaft.

Quote:
"The ball can be left out of the capsule on heavy duty applications only, for firmer TCC apply. Always re-install the capsule".

I did this reluctantly. Could this be causing a problem?