Occulus

So I'm having problems with my 4l60E and I'm confused by all the posts I'm reading. Some people say its a shift soleniod problem, others say 3-4 clutches are burnt up. So I've come to the experts..lol.

Here are the symptoms...on my '98 Trans Am. 120K miles, SUPPOSEDLY it has a rebuilt transmission with a few hundred miles, some tranny parts from "Monster" whatever that is and a 3500 stall. I've had the car about a year, it runs like a beast and I've never had any problems out of it what so ever

I never take it on long trips but the two times I did (about 40-45 miles) I noticed right after it "slipped" in 4th a couple times but it stopped as soon as the car was parked and cranked again. I also noticed a couple times it would shift hard in 4th and a couple times "lugged" in 3rd or 4th (I can't remember what gear I was in ) after it shifted and I had to let off the accelator due to traffic. It has never like going in reverse...you have to shift it let it set a sec then back up. If come to a stop, put it in reverse and try to back up to fast the engine fluctuates to the point of almost dying out but then levels off. I've someone tell me it has to do with the aftermarket cam and some tell me it has to do with the stall convertor


Here's what its been doing the last two days.

1) When it first cranks it shifts all 4 fine, after a few miles it "revs" in 3rd and 4th (even manually shifting).

2) If I go from a stop and give it steady and moderate pedal it feels like it shifts through all 4 gears but I don't know if its actually going back into 2nd or 1st. The RPMs don't jump like it is down shifting but the car is defenitily shifting 4 times. Now, if I give it the gas it "revs" again. I have to take it slow and steady.

Any advice or thoughts on this would be great! I might change the solenoids just to see what happens. I don't think my skill level will allow me to rebuild the whole thing.

Occulus

Some of the parts list if it helps

Thunder Racing Cam Kit-TR224/224 duration, 560/560 lift, 114 lob seperation. Speed PRC Stage 2.5-5.3, TCI 10in 3500 stall, LS6 intake, Hooker Headers, 3" exhaust with 'Y' pipe, Racetronix pump and hotwire kit

mrvedit

First of all, the problems with the engine almost stalling is related to your cam; it just needs to be tuned better for it. The high stall converter makes it less likely the engine will stall, not more.
With a high stall converter the rpms will not change as much during easy shifts as they would otherwise.

The "revs in 3rd and 4th" is likely the 3-4 clutch slipping. (But see my post #5) Assuming the trans was recently rebuilt, this indicates a problem in the clutch assembly, a leak in the circuit going to the clutch or low line pressure for any number of reasons.
I don't think it is a shift solenoid, but it could be the pressure control solenoid. It can even be a defective TPS, MAF or MAP sensor in the engine.

I would hook up a pressure gauge to the trans (it comes with a long hose) and drive while monitor line pressure. It should increase quite a bit when you accelerate. You can buy a trans pressure gauge on ebay or have a local trans shop test it for you.

See my post #11 in this thread (about 3-4 clutch slipping) for more details:
https://ls1tech.com/forums/automatic...o-neutral.html

Other related threads:
https://ls1tech.com/forums/automatic...cks-toast.html
https://ls1tech.com/forums/automatic...-3-shifts.html

With your power level you really need a high performance trans with 7 or 8 friction 3-4 clutch, a 0.500 boost valve (and/or shift kit) and a few other tweaks.

Occulus

Thanks! Ill read over your posts. The guy told me they never tuned it after installing all the parts and I called the hi-pro shops around here because some people suggested it get it "flash tuned" but all the shops said it they don't have the programs for a '98. I'd like to learn to do all this myself.

I'm trying to find the parts list for the tranny that the guy gave me so I can give you all alittle more info. Hopefully ill find it this afternoon. I do know that for a week it was idling very high but I found a vaccum leak where a hose had wore a hole in it. I changed it and the idle went back to normal. I really don't think that has anything to do with it but ill check it again anyway.

Thanks again for the input

mrvedit

I don't have personal experience with exactly what it feels like, but I should have added this:

If it feels like it has some acceleration in 3rd gear, the 3-4 clutch is likely slipping. If it feels like neutral after the shift out of 2nd, it might be Shift solenoid "B"; the trans is basically free-wheeling because the band is no longer applied and the 3-4 clutch is not engaged.

Occulus

It definitely feels like nuetral after 2nd. I find it weird that it only does it after several miles and before yesterday it only did it after those two 40 mile trips (which were a couple months apart and each time it was fine the next day) but I'm not a tranny tech by any means. I'm going to try it again after work and see what happens. If this forum lets me post videos I shoot a quick one to give you more on an idea of what it's doing.

mantycarguy

Scan for codes first. If no codes were set, it is likely you have a small leak in the 3-4 clutch circuit. As fluid temp warms up, pressure will drop just enough to cause the clutches to slip. This may explain why after an extended drive this becomes more apparent.

mrvedit

Yes, always best to first check for codes as some do not (at least immediately) turn on the MIL light.

Solenoid B would have be stuck in the ON position to cause free-wheeling after the shift out of 2nd. While it could be a short in the wiring, it could also be stuck plunger in the solenoid which the PCM would not detect and therefore not give a code.

As mantycarguy says, it probably is a leak in the 3-4 clutch circuit, but it only costs $12 and a little time to replace the solenoid and hope for the best. There are similar threads where people said it was just the solenoid.

Occulus

Thanks guys. I got off late yesterday and didn't have a chance to mess with it, hopefully today. I did check the dipstick, fluid dosnt smell burnt (my basis of compassion is limited though) it was still red but it did have slight black residue, not too much. Hopefully ill get pics today.
The car does have codes thrown when I got it but I'm assuming most of them were because of the aftermarket stuff without a tune up. Ill go by autozone today and check it out and update y'all. Fingers crossed!

Thanks again.

Occulus

Okay guys here's the update so far. Got a video that I'm going to upload in alittle while. I couldn't get it to rev in 3rd or 4th though. It shifted fine all the way to Autozone and back but y'all can watch the video to double check. Which goes back to me saying it only does it when it's heated up.

The codes it threw at the 'Zone
* P1404
EGR valve stuck open
*P0404
EGR system fault (exhaust gas recirculation)
*P0131
Heated Oxygen Sensor- bank 1 sensor 1 low voltage

Here's something else I didn't notice before. I heard that these trannys were very sensitive to low fluid. I checked it today in park on level ground at 160degrees. The fluid covered the 'warm' slot but baaaarrreelly crossed the 'hot' line. Would that be enough to cause my problems?

mrvedit

A video showing it working won't be very interesting. See that every day.
I don't think a 1/2 quart down is going to cause trouble, but why not add it. Many recommend overfilling by 1/4 to 1/2 quart.

Occulus

Lol, I thought the same thing so I didn't bother. I'm gonna try the over fill and see what happens.

Occulus

Btw, what is exactly the 3-4 clutch circuit and how would I go about testing/fixing that ?

Occulus

Sorry for the delay in the update but with school and work I've been extremely busy. I havnt been able to change anything yet. I took the car out for a spin and sure enough right on cue it started its thing again. I pulled right over and put in the missing 1/2 quart it was missing and a little extra. It fixed it right away. We'll see if it lasts, maybe they are overly sensitive to low fluid. :/

tashspop

my cammed motor liked to idle hunt with a o2 sensor fault. fix that and it could solve those issues for you. bank 1 sensor 1 is drivers side before cat.

Occulus

Thanks!