Automatic transmission slightly overfilled. Drain some?

Elkins45

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It’s 1/8”-1/4” above the top cold mark on a 70° day after idling maybe two minutes. This isn’t overfilled enough to worry about, right? I have no experience maintaining automatic transmissions, having driven manuals all my life until recently.

IMG_8513.webp
 
It's irrelevant what he took out. What's important is what the dipstick reads when looked at as prescribed in the manual.
It can be used for comparison. If he took out 3 and put in 4, that could be an indicator of possible overfill.
No one said it was the proper check procedure. Just a data point.
 
After driving it and getting it up to temperature, park on a level surface and check it while it’s idling. Even if it’s a little under or a little over, you’ll be fine. There’s always a little wiggle room, otherwise there’d be messed up transmissions and engines everywhere. Do that and post the results. Let’s see the dipstick after checking it at operating temperature and while idling.

I’d bet that you’re fine.
 
I would remove some. You are basically checking the fluid cold. Typically, a cold check should be within the add section. After a five to ten mile warm up as it should be checked, it will rise significantly over the full mark..
 
Get it up to operating temperature, park it on level ground and check the fluid as per the owner's manual directions. A tiny bit over or under is OK as long as you checked the level according to the mfg's directions.
 
Hot is typically more accurate. I would not drain anything based on that cold reading. Be certain that the car is on dead level ground when you do the reading.
 
As others have said, check it hot. My guess is, you are pretty close if not perfect. Nice work and your transmission thanks you.
Agree. You are close. Take vehicle for a quick run to get the transmission good and hot. Then, with the engine running, wait till the electric radiator cooling fans turn on, then off. With the engine idling, check level again. The stick supposed to read at or near the hot notches on the stick. If vehicle not equipped with electric fans, perform the same procedure, except let it idle 10 min before checking level. Add or remove fluid if needed. If you see bubbles/ foaming on the stick, it is overfilled.
 
I agree with the above: not an issue. Think of vehicles parked on steep inclines, or on an embankment. The level's for 'worst case scenario'?
I've worked on cars - mainly Citroens - since the seventies. I bet I've worked on fewer than 30 cars with automatic transmissions here in the UK. Weird. No particular reason, simply odds. A quick calculation says I've worked on easily 20,000 cars.
 
If you replaced what you took out you should be good
If the level was checked and deemed good before the drain, then perhaps so. Regardless, check the level per the proper process.
But given his pic, I have to believe the level is, at least, pretty darn close.

Just me 2 cents. I often overfill fluids, so I could take a lesson.
 
I don’t have a photo because it was just starting a hard rain when I checked it, but it was about 1/2” above the top hot mark after driving it 16 miles to town and back. I think I’m going to siphon it down to the top mark if for no other reason than to see how much extra fluid it takes to raise the level 1/2” on the dipstick.
 
I don’t have a photo because it was just starting a hard rain when I checked it, but it was about 1/2” above the top hot mark after driving it 16 miles to town and back. I think I’m going to siphon it down to the top mark if for no other reason than to see how much extra fluid it takes to raise the level 1/2” on the dipstick.
It should not exceed the hot maximum line under most conditions, so you’re probably overfilled by 1/4-1/3 qt.
 
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