Ok guys, this may sound like a dumb question but need to ask anyway. I recently had a trans shop install a Transgo shift kit and do a fluid change. When I checked the level, in park, it was above the "safe" line. I brought it back to them and asked if it was overfilled. He put the truck in drive, set the parking brake and checked the level. It was then reading in the "safe" zone. He said the proper way to check the level was this way. not in park. So I'm wondering which way is correct? To check it in park or in drive? Thanks..

 

I've always checked mine in park, but I start the vehicle and move the tranny through all gears and back to park. I also leave the engine running.

 

Your manual should have detailed directions.

In short, drive the truck around (about 20 miles) until fluid is at "operating" temperature. Then with the engine running, put the vehicle in park on a level surface, engage emerg. brake, shift through all the gears allowing time for each gear to engage, put in park, leave the engine running, check the fluid level.

 

Ford and GM vehicles cheked the trans fluid in "Park" position. The only one the I know is that Chrysler Vehicles need to check them in "Neutral" position.