2000 Buick Century Hard Shifting

I have seen TONS of posts about issues with the transmission in the 2000 Century, but no REAL answers. My car shifts perfectly fine cold, but once it warms up it shits hard between all gears. Downshifts are never an issue, just up shifts. To me this sounds like both shift solenoids may be sticking or shot… before I go digging for them though are there any other suggestions? I have already drained the fluid and changed the filter, added lucas tranny stop-slip, drained that out and replaced fluids again… no codes to go by and no high revs before shifts when accelerating…

A lot of people…back in the day…used to buy kits to make their transmissions shift hard. Transman…where are you?

This is a Very common problem. Lots of replacing the pressure control solenoid in the tranny. I did find reference to replacing an intermittent TPS and that corrected the same issue.

Removing side cover to reach PCS is not fun. Usually there are additional internal seals that are leaking in addition to pcs issues. So a new pcs may not fix issue.

People said they replaced the pcs and the problem came back. One guy said he put synthetic tranny fluid in and it fixed it. My father-inlaw’s Century does the same thing when warm. They don’t drive it much and they apparently don’t notice. I think having Mobil 1 synthetic tranny fluid is worth a try.

Wouldn’t a rebuild solve the problem?