I recently installed a TransGo shift kit and ran into a problem yesterday at the track. When I shifted (manually) from 2nd to 3rd, the car delayed and almost bogged for a couple seconds. It never did that before the shift kit so I don't think it has a flat spot in the tuning. I even tried shifting 500 rpm later to get the rpm farther up in 3rd just in case there was a flat spot, but it didn't help. In normal driving circumstances everything works fine. Are there any specific things I could have done wrong installing the shift kit to cause this kind of problem?

The tranny was rebuilt about four years ago by Bowtie Overdrives using there own "special" shift kit, could the two kits have compatability issues? In the video and paperwork the TransGo kit shows 1 piston and spring for the 4th accummulator that sit in the bore above the seporator plate. My transmission had 2 pistons and an orange spring? I talked to a local 3rdgen mechanic who assured me there should only be 1 piston in that bore and suggested I only put 1 back in. I'm wondering if Bowtie OD put two pistons in and then used a lighter spring, so now with only one piston I have the wrong spring? Could this be my problem?

Thanks for any possible help.

 

In normal driving is there a slight 'clunk' during the 2-3 shift? Like the clunk is from the rear? It maybe a timing problem where the trans is in both 2nd and 3rd at the same time.

RBob.

 

Yes, there is a clunk and I believe it was there before the shift kit. I just took the car out and it made the 2-3 shift fine but yesterday at the track I had trouble with that shift on every run.

If this is the problem, is there a solution? Could it have anything to do with the shift linkage? It does have a mega shifter, so I might need to adjust the cable out.

 

At the track did you happen to heat up the tires with a burnout? Check this thread:

https://www.thirdgen.org/techbb2/sho...hreadid=195783

I don't know if he ever resolved the issue.

RBob.

 

Yes, on the burn-out.

From reading the thread, first I'd like to say "Wow," you did some serious research and testing, but I do have some questions.

If this is a feasable solution and would allow me to leave the seporator plate alone, I'd prefer this fix. Looking through my GM manual I was able to I.D. the 3-4 accumlator and the 1-2 accumulator. Are you talking about adding washers to the 3-4 accumulato or is the 3rd accumulator something else.

Is he talking about 2-4 servo and the six washers in there? If so, I believe you said you removed a washer from there and it helped a little. Should I try setting that up "floppy loose?"

 

Is the "3rd accumulator checkball capsule" located in the bore where the 2-4 or "vette" servo resides and if so is this what you were talking about loading up with washers? Could the root of the 2-3 problem reside in this checkball capsule. I had the clunking before the shift kit, but not the problem w/ the full throttle shift at the track. The kit no doubt magnified the problem, but I don't think it was the root of it. I first noticed the clunk when I installed poly bushings in the rear, I assumed the clunk was from the stiffer suspension, but now I think it was probably always there but masked by worn out bushings.

I'm just trying to understand as much as I can before I open up the tranny. The prospect of pulling the valve body again isn't too inviting.

BTW, thanks for the replies and links, they've helped a ton. At least now I know what the problem is. The fix seems to be a bit complicated though.

 

First, DO NOT block or remove the checkball capsule behind the 2-4 apply servo. This will create other problems. Give me a call at 800 7763288 as I have a few questions on this.

 

slow91, if Dana would like to talk to you I would take him up on it. I'm the type that tends to do things on my own and didn't hit him up with this.

As for stacking the 3rd accumulator solid with washers. The 3rd accum is also the 2nd apply piston which is in the servo bore. The stacking is such that the large snap ring is removed and the cover removed. The spring inside is removed and replaced with washers. The cover is put back into place w/o the snap ring.

This will/should cause the 2/4 band to be pushed off faster on the 2-3 shift.

A band too tight would be because the servo pin is too long. As long as the driveshaft turns in both directions no problem here.

The 3rd accumulator checkball capsule is basically in the inner portion of the servo bore. It is accessed through the case from above the valve body. I replaced it as I had the valve body down again, AND, it seems to be a troublesome checkball. A lot of places I read about the 700R4 mentioned replacing that capsule each and every time the trans was refreshed. So I just did it on general principle.

Now, on another note, when I removed the capsule it seemed as though it was too far up in the bore. I didn't expect this and didn't measure the location.

I still wonder to this day whether the capsule was too far into the bore which caused the ball to hit the top of the bore before it seated in the capsule. This would create a leak and maybe cause a 2-3 shift bind.

On the other hand the 3-2 manual shift does not lock up the trans, the 2-3 part throttle does not clunk, and the 2-3 WOT does not bind.

RBob.

 

Okay, just wanted to make sure. That's where you start with 3 thick and 3 thin washers and adjust until you can move the band freely on the drum up inside the tranny. Cool got that covered.

RBob, thanks again for your help. Otherwise, I'd probably be fittling with things that don't need to be tampered with--like the shift linkage. I'll definetly give Dana a call.

 

Solution

I have yet to try it but it looks like we've found the problem. Dana at Pro Built mentioned in one of our conversations that I might need to open up hole "G" on the seperator plate and after reading through the instructions it looks like I messed up.

The directions say, "If plate does not have "G" use gasket as guide and drill hole "G" .110 to .116." I read it as, "If you don't have this hole drill it and drill to .110 or .116." But appearantly if you do have it, you still need to open it up to .110 or .116. My mistake. Dana confirmed having the small hole "G" with the shift kit would cause the 2-3 bind I was experiencing.

Thanks again to Dana (Pro Built) and RBob.

 

I'd say that this is entirely correct. Holes F & G are in parallel (oil feed wise). Stock, hole F is about .210" and uses a checkball as a one way valve. Stock, hole G is about .065". This is with a '92 CS plate.

The shift kit has hole F blocked off. Which then forces all of the fluid through hole G. Without opening up hole G the 2/4 band doesn't get pushed off fast enough on the 2-3 shift.

RBob.