4l80e went soft

[dhcomp]

1991 burb.
Ran trans low on fluid 5 yrs ago. Smoked transmission

Had rebuilt trans installed.
5 yrs and 4K miles ago

Trans had a hard 1-2 shift since installed.

Now it’s gone totally soft.

Thoughts? Any sensor related causes, or does it need to go into the trans shop?

Thanks!

 

[centexk5]

How’s the fluid and inside of the pan look? Shifts soften a bit after some wear.

 

[shady]

There's a solenoid that controls the line pressure.
If that's old enough and has gone bad it could do that

 

[Greg Ducato]

Could be a lot of things, check that fluid level and condition first

 

[Blue85]

Drop a blue pill down the dipstick tube?

 

[dhcomp]

Fluid level is good. Color, smell, all normal.

A slight softening with wear, I get. This is like Shift firmness 8 to 2.

Going to call the shop, see what they can do.

$4k trans that doesnt make it 4k miles is a tough bill to pay again.

 

[dhcomp]

False alarm. Needed to be run hard.

Quick rip on the freeway and it seems to be back to normal.

Guess it earned itself a low mileage fluid and filter change.

 

[Chickntrk]

Almost all things can be fixed by taking them out and pounding on them