Time for a tranny build in the TA

[Swindez95]

Well yesterday I was on my way back to work from grabbing some lunch and decided to do a little spirited driving so as I pulled out onto the rural road I gradually increased throttle to bring the rpm's up. Got to full throttle and when it went to shift into 2nd it hit real hard made a horrible noise and lost forward movement. Let off the gas and when pcm commanded OD tranny bound up so I manually downshifted to 3rd and limped back to work. Had to manually downshift into 3rd so the overrun clutches would hold. So I guess I have experienced the infamous forward sprag rollover. Got it at the tranny shop right now and gonna get it fully rebuild monday. Anyway just thought I would post that FYI. Probably going to tell the builder that it shifted a little to hard into 2nd so that most likely didn't help it live a long and fruitful life. It would literally yank a knot in your neck in high grip situations at part throttle and at wide open throttle the only thing that saved it for so long was the tires loss of traction on the shift.

[96RS Alex]

Re: Time for a tranny build in the TA

That experience sucks, I still have my original 5 speed transmission and at 320K miles on it I should look for another but I'm rolling dice til next spring.

Since yours is an automatic, which is more cost effective a rebuild or a performance oriented upgrade?

Are you a leadfoot? :D

[Swindez95]

Re: Time for a tranny build in the TA

Well I trust the guy I took it to for the rebuild. I do have a leadfoot sometimes and I do want to make a couple passes down the strip next spring if I still have the car. The tranny shop I took it to builds alot of racing transmissions for people in my area so he knows what he is doing. Everyone claims he does a really good job. He has already said he replaces the sunshell with the beast in all 4l60's as well as an upgraded sprag. I may also talk to him about putting a stall in it as well to take advantage of the camshaft installed. He quoted me 950 starting price plus whatever upgraded hard parts and valve body parts he has to install. Im thinking if I do a stall and all its going to be around 1400 or so, maybe a little more.

[ssms5411]

Re: Time for a tranny build in the TA

Most shops around here to rebuild just my 4L60E 3.8 tranny up to hold 500 WRHP is about $1100, and $300 for the 9.5" Billet stall.

[Swindez95]

Re: Time for a tranny build in the TA

Well i got the TA back from the tranny shop 1350 dollars later. 2nd gear band was burnt completely up and cracked like the majove desert. 3rd clutch pack was starting to go out and didn't have much life left in it. My initial diagnosis of the forward sprag was correct, I rolled the one way bearings completely over so it would lock in the wrong direction. The sunshell had a hairline crack so it was almost gone and the torque converter bushing had almost worked its way completely into the pump itself. Good news though was he said it appeared to have a completely aftermarket valve body and electronics in it because it had every sonnax valve upgrade kit installed and the solenoids and such didn't have GM stamping on them. So someone was definitely getting ready to do some serious racing in this bad boy which is what the guy I got it from said. They just abandoned the project for reasons he didn't state. Anyway the shop put the Alto race clutchs in and dialed in the clearances to what he had always had good luck with. Installed the HD borg warner 29 element sprag, the beast sunshell, and even got me a 12in 2800 stall from Dacco to go in it. Drives and shifts like a dream now. Good firm shifts but not bone jarring still enough to break'em loose on the 1-2 WOT and 3rd feels great. Great thing about this stall to is I don't have to goose the throttle while cruising for the Lock-up clutch to lock in, it just locks right in. Overall im satisfied but now I gotta get used to driving with a stall, never had a vehicle or drove a vehicle with one so feeling like im not going anywhere with the slightest throttle imput is a big change over the factory stall trying to push me through red lights with the hot cam.