automatic transmission fluid drain and refill location....

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blockerb
Posts: 127
Joined: Apr 28, 2011 9:58 AM

automatic transmission fluid drain and refill location....

Post by blockerb »

1986 528e stock automatic transmission. OD stopped at 104k i'd imagine 160k+ is more realistic....

So i've searched and have found many references but not the detail i was looking for. I wanted to do a drain and refill of the transmission fluid for my automatic '86 528e, not a flush, but the drain and refill and then maybe do it again next oil change.

I've gleanded that there is a draing plug and i've also seen references to a refill plug/location. My dumb questions:

1. is there a dedicated refill location or do I just refill via the transmission fluid dipstick?
2. Do i have to drop the tranny pan, etc?

not looking for a major flush just incrementally newer fressher fluid. Am i missing a post that describes the process in more detail somewhere?
Mike W.
Posts: 26872
Joined: Feb 12, 2006 12:00 PM
Location: California Whine Country

Re: automatic transmission fluid drain and refill location....

Post by Mike W. »

Pulling the pan to put a new filter in isn't a bad thing, but not essential. Drain plug on the pan, fill thru the dipstick tube.

Fortunately unlike newer BMWs, no need to fill it like a manual, while running, and let the excess leak out. Brick to the head for whoever thought that one up.
Zeta
Posts: 153
Joined: Sep 07, 2017 12:33 PM
Location: Salt Lake City

Re: automatic transmission fluid drain and refill location....

Post by Zeta »

I just did mine because the pan was leaking. If you’re going to pull the pan (which is a good idea, since that will let you clean up the magnets), you might as well replace the pan gasket and the strainer. They’re both very cheap parts and can prevent future leaks and extend your transmission’s lifespan, respectively. Only challenges I had were loosening the filler tube nut, which required a large adjustable wrench with a huge cheater bar and copious swearing, and getting the pan back on squarely without the gasket slipping off of any of the corners, which required an hour of patience while repeatedly loosening and tightening the bolts around the pan, and also copious swearing.
gadget73
Posts: 1176
Joined: Nov 22, 2017 10:30 PM
Location: New Jersey

Re: automatic transmission fluid drain and refill location....

Post by gadget73 »

drain plug is on the bottom of the pan. Drain it, then drop the pan and clean it. I made the mistake of doing a drain and refill without dropping the pan on the 4HP22 in my Lincoln. Wasn't planned, got the fluid out then realized I had forgotten to order the gasket and filter kit so I just refilled it. It stirred up muck in the bottom of the pan and jammed up the governor, which I then had to take apart to fix. No idea how many miles were on the fluid but it was dark brown and the odometer in the car read 182k miles.


Fill through the dipstick tube.

You should be able to just drain and refill at the next oil change if you want to without any issues once the pan has been cleaned out.
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