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hello all, i have a converter slippage issue, i feel like it is in my tune because i can play with the unlock/ lock button in my Scanner, it will lock briefly but then slip.
I have a log attached.
The truck is a 4.8 with a TB converter currently, LS HotCam 4.11 gear 4l60e. i have put a new transmission, and swapped from my FTI 3200 converter to a TB converter, trying to solve this problem... any advice... im cluelesss...
By new transmission what do you mean? Another used one? built? So you had an FTI billet converter slip?
Anyone check the o-ring on the input shaft? Is it a 2000 transmission or is this a swap vehicle?
With a converter the tcc min and max duty cycle should be set to 98. Torque management should be deleted.
Looks like a mechanical problem to me.
the "new" transmission in the truck is a used one that was rebuilt about 20k ago, and the FTI converter wasnt a billet one, just the $400 summit sales. O-ring looked good on input shaft. It is in a 2003 Silverado, no swap. I fear it could be a mechanical problem, but i wanted a second opinion on my tune, being that the last used transmission i put in did the same thing. I've checked misfire monitors, they are all up, also when i tap my brakes it doesnt lock the converter up like it should, could a bad neutral safety switch cause this?
When you tap the brakes the converter should unlock. not lock.Quote:
Originally Posted by DJ_Martin
Usually if the brake switch is bad the tcc won't lock at all, it will never cause it to slip.
Was anything reused between the two transmissions?
The only thing reused was the neutral safety switch and the torque converter(less than 50 miles)
I read that wrong I guess. I thought you swapped the trans with the FTI converter to another trans with a TB converter.Quote:
Originally Posted by DJ_Martin
So you swapped converters, then swapped the transmission?
Does it shift ok? Ever log shift times or put a pressure gauge on it?
Any transmission failure? Like theres not a chance that theres garbage floating around in the cooler or the converter contaminating the new stuff?
It shifts fine, just whenever it gets to OD the converter wont lock.. and yes, i swapped converters then swapped trannys. I did mess up the 3-4 on the original transmission, so it could be possible some stuff could be floating in the cooler, but that was three transmissions ago, what would be my best way to flush it? Would i use regular transmission fluid or some sort of trans flush?
You don't flush it with anything. Just take the filter apart, if theres crap in it, theres still stuff in the trans/converter/cooler. Sooner or later it'll all get stuck in the filter or valve somewhere. Some kind of flush is not going to be any different than fluid.Quote:
Originally Posted by DJ_Martin
The problem is when a piece of it gets stuck somewhere.
If you have the trans pan off sometime soon check the filter in the tcc solenoid snout, check the solenoid snout for cracks even very small cracks, make sure the tcc solenoid o-ring is good and fits snug in the bore. It's real easy to crack a solenoid snout. A lot of people rebuild these transmissions and reuse the electronics but test them. A crack might go un-noticed but it'll pass an electrical test. Other than that I'm out of ideas.
Except for the tcc regulator valve bore in the valve body. I noticed your tune doesn't have the DTC for trans component slipping P1870 so I don't know how it doesn't pick up the slipping and go into limp mode.
But the most common thing as far as I know is the tcc regulator. People have all sorts of tricks to eliminate the wear problem. I has to be fixed properly, either reamed and an oversized valve installed, or a transgo valve, Sonnax, even a Fitzall valve. I'd almost guarantee something mentioned here is the problem.
Scan for TCC_MODE and see if it reports LOCKED or --3--
(do not command lock, for reasons such as misfires).
Look at TCC_Duty and see if you're getting full apply
commanded. Look at force motor current too. Different
converters need different delivered pressure to not-slip
at a given input shaft torque.
Look for transmission component slipping codes, maybe
immature, which once set will inhibit lockup until next
key cycle.
His scan file shows duty cycle and commanded on/off. It shouldn't be slipping. It also shows misfire tables maxed out....etc. It's been tuned to not react to tcc slip as far as I can see.Quote:
Originally Posted by jimmyblue
This is old info that still applies to 4L60E/65E/70E transmissions.
Quote:
Originally Posted by Jason B
Yesterday i had adjusted the force motor current, the truck drove normal;however two new things i noticed. 1) p0894 showed up, and two, the fluid temp got up to 230. I have a tru-cool 40k and the factory cooler in radiator on it still... and i averaged about 150rpm slip at 55-60 mph.. so now im thinking start by changing the TCC solenoid, then go from there
It's not the force motor current. I compared your file to 3 vehicles I have and they have the same force motor table. All you did was shove more pressure through a problem and it caused it to clamp more but still slip.Quote:
Originally Posted by DJ_Martin
My best suggestion is FIND the problem, then fix it.
Sure, pull the tcc solenoid out and look at it. If it's not bad then what?
Should pull the valve body, check the tcc isolator bore, maybe have a local shop just ream and install a new valve if wear is found. Otherwise you're accelerating the death of your converter.