Question : 94 corsica V-6, 4T60-E,shift prob

[racerxpl]

Shifting into 1st gear in drive slippage, but will shift by manually downshifting fine, changed fluid & filter, no change, changed modulator, different results, still not right, ABS?, vacuum modulator or possible sensor? Can't seem to pinpoint exact problem, 3.1L. Thinking about seeking counseling, please any help appreciated.

[IsaacHayes]

rebuild or swap low mileage junk yard unit...

car-part.com ...

Once I get my orange car done, I might go ahead and take the stock 3400 that I will have pulled out of it, and get a low mileage (40k) trans with 3.29 FDR, do some small mods to it, then slap both into my blue daily driver.. Would be nice to have a trans that was snappy and fresh again. Mine does not "bite" hard anymore going into 1st.

You might want to try some GM automatic transmission seal conditioner... It fixed my issue of it not going into gear when cold until it warmed up. It could be a seal issue or something leaking.. But other than that not much else you can do other than do a rebuild (get a transstar trans rebuilt kit, get ATSG book, and the related hard parts to replace/upgrade the factory stuff...)

[gpse3400]

Shifting into 1st gear in drive slippage, but will shift by manually downshifting fine, changed fluid & filter, no change, changed modulator, different results, still not right, ABS?, vacuum modulator or possible sensor? Can't seem to pinpoint exact problem, 3.1L. Thinking about seeking counseling, please any help appreciated.

I bet you wore out the oil pump shaft for the trans. that wil cause bad shifting except in manual select...