grnd prix Transmssn shifting very hard

[dmen921]

Hello all, I'm new to this chat. What a great idea though. I have a Pontiac Grand Prix GT that I bought new in 2000. Approximately 2 1/2 years ago I noticed that my transmission started shifting really hard once the car had been driven for a little while. This started out very infrequent and then eventually got worse and worse. I took it to a Transmission specialist and they ran diagnostics on it. They determined there was some type of computer chip that was bad. I had it repaired for over $900. That did fix the problem for about 2 years and recently the problem has started back up again. It seems obsurd to have to replace this every 2 years at a cost of $900. Does anyone have any insight for me or has anyone had this problem with theirs? Thanks for all your help.

[maxwedge]

Have it scanned on a trans capable scanner they can determine any slippage that would force the trans to compensate with high pressure settings, there are problems with valve body and the pressure control solenoid that could cause this.

[harv405]

I had a similar problem with my old car. Took it in for a transmission service and havent had the problem since.

[rbsteve]

Do you do regular transmission oil changes ? i think they recommend changing it about every 2 years, which is about the timescale you are talking about. I know that my car shifts noticeably smoother after a change.

[richtazz]

I agree with Rbsteve, go have a new filter put in, but don't let them talk you into a flush/fluid exchange or you'll be buying a new transmission. Just have them drop the pan, change the filter, and replace only the fluid that was in the pan when you dropped it out.