first question (2000 SL1)
 

it may or not be a problem... but the car drops out of O/D going downhill(actually downshifting if you brake) and sometimes doesn't want to go back in after reaching the bottom of the hill, even after accelerating to 50+ mph... it always eventually goes back into O/D though...

i read that the car was built after they made the transmission ("read driver input patterns", or some stuff)... is this sort of behavior normal? drives great otherwise, just not used to the tranny acting like it does...

bump, is the above mentioned behavior normal for a late model Saturn with the auto gearbox? you know, after they got rid of the economy/sport button...

I'd swing by a "Saturn friendly" dealership, and have them check the transmission computer for error codes ( or anywhere else, for that matter)

a code reader didn't show anything... but i don't know of a "saturn friendly" dealer near me...

sorry no help from here my s cars are all 5 speeds

That is usually a function of cruise control, but to act the way you describe, it would be a cruise control gone amuk.

Call GM customer service, they know all Saturn friendly dealers

When I had the automatic in my car it was a very, very funky little transmission. It would downshift under braking at times, but when I made it downshift on the highway to go faster, the revs would jump high then slam down into gear, as if the torque converter was letting loose. Mine was also missing the econobox/performance mode switch. So i think it was trying to econobox me all the time

I remember reading somewhere these transmissions learn how you drive, seeing that its your wifes car maybe your driving it abit differently? I remember when I lent my brother the car it would shift early for a few miles, cause hes slow hahaha

Well ... now that I think about it, I did have some problems with the automatic tranny in our '98SL2. Would be driving down the road (level road) in cruise control mode, but could feel the transmission going in and out of "O/D". The tach would mirror the problem with a 600rpm jump/drop as this occurred.

Finally got the dealership to connect a set of gauges to the transmission, and take a ride. Fortunately, the car was cooperative, and misbehaved for the tech. Final decision was that the final control valve for the "O/D" was not locking up properly.

At the time, we were still under warranty, so the dealer simply dropped another transmission into the car, and away we went. Don't know what it would take to repair such a problem ...

from what you said I would guess valvebody rebuild, next best thing to do before dropping it

kinda what our car does... it's only problematic on the hills where we live where it tries to "econobox" you going uphill and it downshifts going down... if you pound the brake pedal going into a corner, it drops a gear for you, trying to be sporty(which i guess is cool) but i don't drive her car fast enough to warrant any sporty trans behavior... i would prefer for it to drop gear when i open the throttle going uphill, without it having to bog down to like 30 and then kick down and turn nearly 4000 RPM, and i would like to go downhill without it downshifting and turning 3000 RPM just to try and hold the vehicle... i guess what i'm wanting is a "dumb" automatic that doesn't try and read driver input patterns...

Well, the hills of WestVirginia are much more than the flatlands of Mississippi. I must admit, I've never felt the car drop a gear to retard speed on the downslope while running in "cruise", but I guess anything's possible ...

Our diesel f350 would drop 2 gears while we were towing to keep 72 MPH, thing was close to redline and it was on cruise control

The last thing I would try before rebuilding the valve body and going through that head ache is try disconnecting the battery for 30 mins and see if it still does it. I know that some of the auto trans have a computer that learns your driving habits and tunes your shift to those habits. Some times you can reset the computer by disconnecting the battery for awhile. Mind you I didnt read all the post above me if I repeated something I'm sorry.

note, this is not using cruise... the car isn't equipped with it,lol... car downshifts as you brake and if you're going downhill, it stays in that lower gear... wouldn't be an issue but it is reluctant to return to the higher gear, like it thinks it's still on the steep hill...