I have '99 Deville with 79,000 miles. Sometimes when I start from a stop (and less frequently when I'm accelerating) there seems to be a grinding noise coming from the transmission. I've heard/felt this when the car is cold or warmed up. It also feels like the car is hunting for a gear. Once it finds first or reverse the noise goes away and the car takes off with a bit of a lurch. The transmission fluid is clean, doesn't smell burned, is a clear reddish color, and at the correct level. Shifts between gears -up or down - are quite smooth under normal or hard acceleration or braking. The transmission doesn't make other noises that I know of. Sometimes the traction control, ABS and SES lights come on. They go away if I restart the car. I don't know if they are related to the problem with the grinding noise. What could be the trouble?

 

if the transmission is hunting for a gear, there will be codes, and the solenoids need replacement . They cost around $40.
IF they are hunting and continue to hunt, you will need a new transmission as they wear out other parts. Cost: $2,500.

the grinding, i have no clue.

codes please.

 

Here are the codes.... It was actually easy to get them (HVAC OFF Button + Warmer Temp. Button with ignition on). I think I was able to turn off the Traction Control using the button in the glove box. It seemed to help, the last time the grinding began the traction control system engaged. I don't know if it comes back on when you restart the car. The ABS and Traction Control warning lights went off on their own, but the SES light is still on.

I. PCM Codes
P0440 (Evaporative Emission (EVAP) System)
P0603 (Control Module Long Term Memory Reset)
P0741 (TCC System Stuck Off)
P1574 (Stoplamp Switch Circuit)

II. IPC Code
B2710 (PASSKey Open/Shorted Pellet)

III. ACM Code
B1341 (Air Mix Door Two Movement Fault)

IV. TCS Code
C1226 (RF Excessive Wheel Speed Variation)

V. RFA Code
U1000 (Class 2 Communication Malfunction)

There may have been a TSB on this problem. I'm not sure where to look for them (for free that is). I saw a posting on a website, but it was a paid access site. NHTSA has a website that summarizes the TSB's at http://www-odi.nhtsa.dot.gov/tsbs/