mk3cn4

iTrader: (3)

I have a 98 Camaro, all stock except Vig 3600 stall and mail order tune.

Did not slip for a long time, like a year, and now I have a strange symptom.

When the car is cold, TC holds solid, as it warms, either the TC or trans slips in a STRANGE way, if I go to 3rd and immediately back to OD to unlock/lock (tune stops TC lock in 3rd so this unlocks and locks the TC again) then it locks solid for another 10 minutes or so.

BUT, WHEN it slips, it slips strangely like a modern TC where light throttle raises the tach slightly and a little more throttle makes it grab better usually making the tach go down and lock tighter.

I don't know enough about trannies, is this a clue like line pressure problems or something like that?

I have a friend who's going to stop by in a few days to make sure it's being commanded to lock while it's doing this and will check for codes (not sure if the mail order tune has eliminated any code generation or whatever, no lights on the dash and I know my EGR and rear O2's are tuned out).

For the time being, I was considering doctoring the wiring to prevent the TC from locking so it wouldn't slip-burn out that clutch in case it's something minor or unrelated to the TC.

So, the question is, does this sound like TC clutch wore out maybe?

Fluid is right on the full mark, clean. Other than the slip in OD while locked it feels just fine otherwise, has strength to spin tires 1st and into 2nd. 3rd and 4th shifts feel very tight and solid, no redline bumps under WOT, no other symptoms.

Tranny has 100k miles on it. TC has high mileage too, but I'm all highway and it should have relatively light wear on that clutch I'd think.

Thanks guys!!

LS_Canuck

It's possible that you may have a leak somewhere in the TCC hydraulic circuit... Is there any way for you to check the AFL pressure (mainline pressure) when the TCC is applied?

mk3cn4

iTrader: (3)

I have a friend who has OBDII software on a laptop that can do all the extended GM stuff including trans data, I will add that to the list to see if it can check.

I have another buddy who might have one of those line pressure guages, yea I did read another thread describing a scenario where higher RPM's made slipping stop because some sort of pressure was low and RPMs raised it, so I am going to try to check that too to see if line pressure is too low or something.

Thanks!!! If anyone else has anything I can check I'd appreciate it!

mk3cn4

iTrader: (3)

Until I figure this out, can someone tell me what color wire to pull on the trans harness so the TC doesn't lock so I drive this car to work tomorrow? I think I saw someone mention green in another thread but it was unclear.

I'm afraid that even though the tc is only slipping a little, I am risking my whole transmission because the tc clutch material might harm it.

Or is that something I should be worried about? What is the worst case scenario that I allow my TC clutch to keep slipping like this?

Gilbert@Ace Racing

I think you're on the right track... get some good data and then get back to us.

You'll be looking to know what is being commanded and when. Also, be sure to monitor line pressure as it becomes symptomatic. There can be a few reasons for this condition... everything from worn valve body bores to an excessively worn converter clutch disc.

What is the fluid condition?

g

mk3cn4

iTrader: (3)

In the spirit of the forum and for the benefit of others who may be searching for this, here is what I have come up with.

Two things: first, I am absolutely convinced my problem is that apparently very common worn bore problem. My TC locks for 3-5 minutes rock solid and slowly decays to where it slips, and I pull down to 3rd (TC tuned out in 3rd) and let the revs come back and it's good in 4th locked for another 3 to 5 minutes. So, it's a pressure leakdown gig somehow. When it's locked, it's solidly locked and holds all the way through to 50% throttle or whatever it is that kicks it out. I really can't believe my TC clutch is gone.

But, here's the cool part. I was able to snip a single wire to get the TC to not lock because the "mail order racing tune" I have apparently tuned out the slipping tranny code. Even with a 3600 stall, it's not that bad without lock on the highway, so I think I can drive it until I can fix it now. For details here is the parallel thread I posted earlier:

https://ls1tech.com/forums/automatic...tc-lockup.html

Clearly I was wrong on the wire color in my original post, I think it's because I am a 98 which has different wiring or something. But, at this point for the TC slippage, I have ordered the TransGo orangebox shift kit which has the remedy for this worn bore problem, and I can now drive the car until I get around to installing the shift kit. My guess is I install this shift kit and patch up that wire and I'm golden. If not, maybe I'll just run lockless!!

THANKS guys for the input you guys all throw at us normal joe's. It's greatly appreciated!!