98 GP GT tranxaxle fluid questions

[Wide_Track]

Hi,

I drove (over 30 miles highway) to pickup wife the last weekend, was park idling for about an hour. While parked I noticed the temperature went very high (~ 235 degrees). When taking off experienced a hard shift into second gear. It seem to stop after the temperature (~ 185 degrees) when down, transaxle shifted like normal. Checked transaxle fluid was in cross section but darker than normal. I believe the transaxle fluid may have broken down. Currently, planning on changing transaxle fluid and filter on a 98 Grand Prix GT 3.8 liter on Sunday. Questions: Is this a correct assumption (fluid broken down)? Also, is there a tightening sequence for the pan bolts? Do not own a torque wrench, planning on hand tightening… will this suffice?

Also, any comments or suggestions are appreciated.

Thanks,

Nu Sky

[troy1]

Fluid does break down over time. Sitting there idle you have no airflow over the cooler so temps could rise. No there not really a torque sequence just uses common sense by working from the middle out. As for a torque spec roughly 90-115 inch lbs so lightly hand tight with a short ratchet should be fine. Have 8 qts of a high quality DEX III fluid on hand put 6.5 qts in to start with and add from there. You can have the fluid slightly over the crosshatch when warm so don't worry too much.

Oh and don’t throw away the reusable heavy OEM gasket keep leaks away and reuse-it

[BNaylor]

What mileage does this '98 GT have and when was the last transaxle service?

I always use 120 in-lb or 10 ft-lb on the 23 pan bolts. And.........................



With a torque wrench. We as humans are not properly calibrated so use the right tools for the job.

[Wide_Track]

Hi troy1 and BNaylor,

Thanks for the quick response.

I appreciate the detailed information, very helpful. The GP has over 200,000 miles on it. The fluid and filter was changed last around 100,000 miles. I drop the ball here because of being too busy and not knowing anyone reliable.

I will check back here prior to purchasing the fluid and filter this evening. Again thanks!