capot

Which is the correct way to check the transmission fluid? I've been taught that you pull the dipstick, wipe it re-insert and check again. According to the service manual for my wife's '78 Olds Delta 88 Royale it says to "immediately check the fluid level" . So I drive the car for about 1/2 hour or so, get it warmed up, pull the dipstick, wipe it, re-insert and it looks dry. I add some fluid, go through this again. This time after driving and parking in the driveway I pull the dipstick and it shows 'full hot'. Is this correct or is it just reading fluid splashed up on the dipstick? The transmission is a THM-350.

Chris

oldzy

I always check while running, put in reverse then drive perhaps, then put in park... pull, clean, then check again.

MDchanic

Always wipe first.
The "right away" refers to running it through the gears, then putting it in P, then getting right out and checking.
If it always reads low, then it may need more fluid. These things can take a tremendous amount of fluid between "just visible on the bottom" and the "low" line, or they can just take 8 ounces.

- Eric

capot

Thanks to both of you. I thought you were supposed to pull, wipe, check but the service manual neglects to mention the wipe step. I'll check it out again tomorrow evening after work when it's still pretty light outside.

Chris