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Have a small leak of trans fluid so check it every so often. Had car running at temp, checked, said to add a pint. Added pint. Dipstick seemed to be at full.
Few days later, check (cold) and appears way overfilled, start back up at temp, says add pint. I’m very wary to keep adding because I don’t want to overfill. Is this dipstick smarter than me
Ive notice addition leak near pan, probably need new gasket. Should I keep filling while temp warm? Feels inaccurate for some reason ugh
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I'm not too sure, but your post implies that you checked the level without the car running, saw it apparently overfilled?
Trans fluid should always be checked with the car running and in Park. Ideally it should be warm, that is, if you touch the wet end of the dipstick you should be able to hold it. In that case, the level should be just about at the "Add" mark. That is fine and fluid should not be added. If the dipstick is too hot to touch, then the level should be at the "Full" mark.
I have an annoying "weep" from the speedo drive, which only manifests itself after the car has been standing for a week or more, as the fluid drains out of the converter. It collects in a drip-tray and I monitor the amount of fluid in there, which gives me an idea if I need to think about checking or adding. I keep promising myself to put new O-rings on the (almost new) drive connector, but it such a pain to reach on my '78 that I have put it off way too long!
I get his point: There seems to be a big difference between cold and warm/hot.
Tranny fluid expands quite a bit, so the OP's doing it right by checking warm and adding fluid when warm. The reason it seems to expand a lot between warm and cold is...a lot of tranny parts protrude down into the pan which displaces a lot of volume inside the tranny pan. Think of it like you put water in a glass. Then you took a smaller glass and pushed down inside the first glass. Only a little downward movement raises the level quite a bit. That's kind of an exaggerated example of what's going on in your transmission too. Also, when the engine is shut off, some fluid is going to drain back into the pan, which also throws off the level. Which is why you check it while the engine is running (engine warmed-up).
Try to figure out where your leak is and resolve it if you can. But keep checking and attending to the fluid leak like you have been..for sure.
Trans fluid question
