transmissions

1999 PONTIAC GRAND AM

227,000 MILES • 6 CYL • 2WD • AUTOMATIC

TDEW

MEMBER
1 POST

I recently repaced a 1999 motor and tran with a 2000 motor and tran with less mileage. My problem is that now the tranny sometimes after about 30 miles start to have a hard shift. I've driven over 3000 miles since the change over. If I shut the car off it starts to change smooth for approximately another 30 miles. Any ideas on what the problem might be?

Jan 23, 2011 at 1:28 AM

JACOBANDNICKOLAS

✓ASE Certified Mechanic
110,194 POSTS

First, we always recommend direct fit parts because sensors don't always work properly from one year to the next. If the check engine light has come on, have the computer scanned to see if it is a trans codes stored. If no light has come on, make sure the trans fluid is full. To me, it sounds like a bad shift solenoid. However, since it fixes itself when you turn the key off, it could be there is some incompatability between the PCM, trans control module (newer model)and the solenoid.

Mar 15, 2011 at 6:39 PM

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