Philip Pugeau

I have a high performance rebuilt 4L60E, 3500 stall, Transgo shiftkit. With a hard enough shift 1-2, the transmission will hesitate shifting 2-3 and bounce the rev limiter, then shift.

Having the trans tuned to shift at 5500 rpm, rev limit at 6500, 2-3 will function as programmed with a soft 1-2. However, on fresh pavement or at the track where 1-2 reaches a certain shifting pressure threashhold, it will pass 5500, climb to 6500, bounce the rev limiter, then shift 2-3. Any ideas that I can pass on to him?


2001 Firebird Formula A4
383 6-bolt 11:1 LS6 heads+cam, forged internals | Dana60 4.10 | BMR K-member | BMR control arms + Panhard | PST Custom driveshaft + 1350 yoke| FTI3500 stall 4L60E | stock air cleaner and exhaust! | P245/45R16 NT555R
345 rwhp / 391 rwtq
Built at Next Level Performance Orlando, FL

Philip Pugeau

So, has this problem stumped everyone, or has my question been answered somewhere else, and I just need to do some more thread mining?

Gilbert@Ace Racing

Just saw the thread myself, been busy in the shop lately. My apologies.

My question would be who built the transmission? Point being not all "high performance" transmissions are the same. A HD-2 kit does not make it a high performance transmission. It make it a transmission with a HD-2 kit. There is much much more to it than that. Knowing who built it will shed a bunch of light on your issues.

It can be an overly aggressive servo setup, an incorrect PCM tune, a sloppy build or several other issues. Not to shed a negative light on your build, but the devil is in the details. Can you tell us more about what is inside the unit itself or who built it?

g

Philip Pugeau

Yes, absolutely. Hey man, I can appreciate being busy! It was built at Transmissions Plus in Kissimmee, FL. Jesse runs the shop. He was referred to by Greg at FTI where I picked up my 3500 stall, so I want to trust his capabilities, you know?

Jesse said that he would put the Beast in, hardened planetaries, sleeve the housing, better servos, HD trans cooler, polyurethane mounts and many more awesome things that I can't remember right now. I can get more details if needed.

He said it can handle at least 600 hp, without a doubt in his mind. I told him that it would get abused every day, and it has taken it. I didn't notice this weird issue until I had drag radials on the car, and started having fun with the first gear. This presented itself especially well at the track, with the ultra sticky VHT hooking up. The shifts are still very solid and crisp after two years of fun.

So, having his guy do a ridealong with a real time scanner, he said the servos were working, and sure enough when I stayed WOT at the rev limiter, it did shift. That's how I broke valvesprings in the old motor.

Being told that it must be the tune, I had Geoff at Next Level Performance, who has done everything else to the car, help me. We also used a realtime scanner during the shifting process. Not to be too redundant with my explanations, I will describe again how he programmed the trans to shift at 5500, rev limit at 6500. As long as the 1-2 shift is soft enough, it will shift through all gears at 5500.

But, once I get the car on some fresh pavement, or take it to the track, banging 1-2 causes 2-3 to pass 5500 all the way to 6500 and bounce the rev limiter, something I don't like doing with a new motor!

I have the capability to post a video of this in action, if necessary.

Thank you for your response,
Philip

s13vette

iTrader: (1)

wow sorry to hear bud. I'm having the same problem, I installed a 3500 245mm circle D stall, and 9 clutch setup for my 3-4 pack with a full TCI kit, and a Transgo HD-2 kit. The car amazing 1-2 but when i hit 2-3 it bounces of the revs and then shifts. I have also a 4.09 gears in my 240sx so i was told sense i have the gears and now the stall the shift points are out of wack.
lmk if u figure this issue out.

Philip Pugeau

I just read a thread on a pickup truck forum that explained how the Transmission Adaptive Pressure works on the 4L60E. The post recommends that the values for the TAP should be cleared when this much extensive replacement has occurred.

The computer learns how to shift the trans as you drive it, so by modifying line pressure mechanically by a shiftkit, etc, the actual shift point can change away from the calculated shift point.

the thread : http://coloradofans.com/forums/67-te...explained.html

Mike Morris

iTrader: (55)

Go back in your tune. Take 3 MPH off on the shifts on both tables(WOT and the other one). You made no mention of changing the speed. The ECU looks the speed first on the command. Again 8 times out of ten its the tune when you have this problem. I bet the trans is fine.

Philip Pugeau

I hope the trans is fine. However, the tuner has adjusted the speed tables as well. It's just so strange that it would work as it's programmed, except when the 1-2 shift is under enough load when the tires grip really well.

s13vette

iTrader: (1)

Hey man just incase u havent found the problem... i found mine so here it is.

I was having the same issue till i got it tuned. We took away 3-6 MPH all around and set the rear end on my 240 and walla car is running perfect. Hope u fix ur issue.

Philip Pugeau

Tried subtracting even more speed away from the 2-3 shift and the trans is still having no effect. It has already been tuned for the stall, gear and then some.

silverz28camaro

iTrader: (20)

My GUESS,
1.) your 3-4 clutch pack is worn out from 2 years of day to day abuse and now thw clearance is over .100 and is causing a delayed 3rd gear engagement..I see this alot on stock units with alot of miles and during teardown I measure .100-.200 3-4 clutch clearance...after the rebuild and new clutches set between .050-.070(stock builds) the 2-3 is cured..

2.) possibly the tune?? Even though your commanding a shift at 5,500 doesn't mean its going to shift at that rpm, the computer MUST see a set mph also, with a stall converter this moves the desired mph down, for example if a stock stall shifts at 6,000 at 70mph, add a stall and at 6,000 mph you may only be at 67-68mph.

3.) I had a converter clutch go bad in my car once from overheating/hop lapping...this caused to much material to build up in the converter and made it very inefficient, during my desired 2-3 shift at my set 6,600rpm/76mph..the converter slipping would cause my car to reach the rev limiter at 7000 when I was still only at 74mph....sure if I stayed WOT the car wouls still acc. while hitting the limiter and then reach 76mph and shift....new converter fixed this issue.

Of course there are other issues that may also cause a 2-3 "flare" but these are the common ones, check the tunes mph request, possibly data log it and note what mph you are hitting the rev limiter at, if you have to JACK the tune out of normal range to get it to shift I would then suspect the 3-4 clutch back and inspect under the 3rd gear apply piston, if alot of material is built up here its from the converter clutch...even if its clean and only the 3-4 is worn I would still recommend shipping the converter off just to have it re-freshed.

Philip Pugeau

Even if the converter and trans are way overbuilt for the power it receives? There is zero slip in the shift in all gears, and the fluid was replaced very recently during the engine build, after the two year driving stretch. No contamination.

gofasterdammit

you might have a worn accumulator piston pin bore. id check it out. or sonnax sells a servo release valve that releases the 2-4 servo quicker and fixs the 2-3 flare at wide open throttle. it also fixs band burn up and 3-4 clutch burn up. hope this helps?

Philip Pugeau

A quicker servo release valve might be the way to go. Sounds quick and affordable. The trans does feel like a stuck valve anyways. How many of these upgrades have you done where the 2-3 flare was an issue? In the cases where the trans was tuned properly?

You can see a better description of the case on my other post "What's your shift point tune?"

stephen4036

how much was the labor at this shop in kissimmee? im in orlando and im going automatic.

Philip Pugeau

I can't seem to find my receipt, but I think parts + labor was $2000 to $2500. I will still recommend the shop. Give Jesse a call for the labor (407) 935-0223, I'm not sure how much it will be.

gofasterdammit

most of the transmission we build are for stock vehicles. this problem is almost always a WOT issue and only a few people ive seen had this complaint. lead foots usually. i can say that valve did fix the 2-3 flare everytime. including my own car. im new to f-bodys and my tuner said he has fixed that with programming but i feel that if you already had the flare for a while the band and clutches will so some glazing from the slow release. i do think it might be worth a try though. good luck!

Philip Pugeau

Transmission works perfectly now. Seemed to be a slight error in the speed calibration. Recently put some NT555R 315/35R17's on the back, which dialed the speed down to its true value. It was high by 5mph at 80.

With even MORE grip going into 2nd, one would figure that the trans would have an issue like it has been. Nope, just the speed tuning, enough to cause an issue.

What a relief that the trans is perfectly good, which causes me to recommend Transmissions Plus in Kissimmee for anyone in CFL who wants a badass automatic for your everyday lead foot.
__________________________________________________ _____________
2001 Firebird Formula A4
383ci 6-bolt 11:1 LS6 heads+cam, forged internals | Strange S60 4.10 | BMR K-member | BMR control arms + Panhard + adj Torque arm | PST 3.5' driveshaft + 1350 yoke | FTI3500 stall | built 4L60E | K&N intake | hollowed cats, stock exhaust | 315/35R17 NT555R
345 rwhp / 391 rwtq
Built by Next Level Performance, Orlando, FL
4L60E built by Transmissions Plus, Kissimmee, FL