4l80e lockup problem
 

having some problems with my 80e lockup, when i come to a stop after the trans is warmed up its making the converter go into lockup and stall my engine out.

i replaced the lock up solenoid with no luck, i also just put in a new circle d 3200 stall thinking it was my tcs 2800 but im still having the same problem.

but with my tcs 2200 stall i did not have this problem, could this maybe be a problem with the trans tune or what?

i did a search online for this problem and find lots of info but no ones seems to post what the fix was.

any help would be great :hail:

no one has any ideas? :poke:

Either a sticky valve or a cross leak in either the pump or the valve body is what I would suspect. Just looking in my sonnax book and they have a new valve out to address lockup issues. One of the complaints is TCC apply and release issues do to a worn bore in the valve body. This does require a tool to bore the valve body but it looks like this might be an area for concern with a complaint such as yours. Sonnax Part # 34994-18k. Maybe try to install a different VB to see if it corrects your condition. HTH Vince

Have you put a scanner on it to determine if the ecu is calling for lockup?

Good point but I really feel that the issue is a cross leak or a sticky valve not a programming or electrical issue. Here's the thing according to the oil schematics this trans should not have TCC operation in 1st gear because it uses what they call 2-3 drive oil. This is really what starts all of the fluid for TCC operation. This oil is not present until second gear when the 1-2 shift valve goes to a released position. I feel that the problem is either in the pump or the valve body. Vince

i got this info from Chris at Circle D

There is a spring you can install in the pump to help with this. I see it on a few 4L80s, they have low line pressure at idle and the clutch will drag some. I can get you a spring. I have also had a few guys fix this in the tune with the EPC settings.

Chris

X2. VB, Pump, or converter issue.

Should of also mention the cross leak as well, like Vince mentioned.

Chris

My 80 was doing the random lock/unlock and neutraling out at part throttle. I pulled the valve body and had the TCC and AFL valves replaced with upgraded parts, either sonnax or transgo and its worked great ever since.

Those are the two area's in the valve body that I address on my builds. The AFL valve on these units may not need to always be replaced with upgraded parts. However it should be looked at closely on every build. This valves main purpose is to regulate oil pressure for the solenoids and worn or improperly machined AFL bores can cause many issues. The TCC valve upgrade is a good one to do and I do this on everyone I do. HTH Vince