4T60E Won`t shift out of 2nd

[Jewelnohio]

88 cutlass supreme Fwd 2.8L . Sat for 2 years , tranny was working fine when parked . Now it starts out in 1st , then shifts to 2nd , then it shifts to what seems neutral. Unplugged harness made no difference . Any ideas ?

[bszopi]

Check the fluid level?

[bud36light]

Check the simple stuff first like the mod vac hose-cracked maybe. Hell since it sat for awhile make sure somebody didnt fivefinger any spare vac hoses on the motor or dirt dobbers didnt make a home there or anywhere else. For sure check the fluid level. Hope that isnt same prob I had with my 4t60e- it lost reverse,3-4. It stripped the teeth off of the clutch drum. BTW is that really a 4T60E?

[bszopi]

He brings up a good point... The 60E didn't debut until 91, and it was NEVER offered with a 2.8L. So it would either be a 4T60 or 3T40 (although I doubt the latter was ever found in a W-body).

[mihela816]

yes the 3t40 was offered in the w-body

[Jewelnohio]

fluid is ok, changed the mod . still same problem .Any Ideas

reverse is ok . 1st and second ok . fluid is ok . changed the vacuum mod. and still no 3 or 4th . Any ideas ?

[RednBlack]

Try a bottle of Lucas Trans Fix. May have a stuck valve due to varnish. This stuff is safe too. Contains no harmful chemicals that will eat an internal seal, however, I recommend changing all seals that were exposed to ouside air if the car sat that long. Otherwise it will start bleeding all over your driveway. Don't do the seals yet! Run the Lucas to see if it eventually fixes the problem. May have to drive it around for awhile, preferably not on an interstate, baby it. If it does start shifting, then drop the pan and replace all external seals and the pan gasket. You might consider using Slick 50 Trans Treatment when you refill.