Transmission Gasket installation

Joined
Nov 27, 2017
Messages
27
Location
Massachusetts
After 140,000 miles, my transmission was shuddering like crazy. This is a 2012 Lexus RX350. Lexus claims it's lifetime fluid and a sealed transmission which is a bunch of bull. It looked like motor oil after 10,000 miles. After 3 drain and fills, the shudder is almost nonexistent. Because I can't leave well enough alone, I decided I should replace the filter, plus I'd be able to drain much more than I'd be able to just from using the drain plug.

Anyways, I ran into a situation. I removed the transmission pan and gasket, replaced the filter, cleaned everything, but there's this annoying trickle that won't stop. This trickle is coming from somewhere up in the transmission. It is a very, very light trickle, less than a runny nose, but it clings onto the mating surface in one corner keeping me from having a dry surface to bolt the pan and new gasket onto. It's driving me crazy. The gasket is a rubber coated steel gaskets oem from toyota. What do I do? I'm letting it just drip overnight and maybe it will stop.

Also, when I removed the fill plug on the side of the car, the stupid crush washer fell somewhere when I was taking out the bolt and I can't find it to save my life. I have no idea where it is. I'm going to order a new one if I can find the part number, but in the meantime can I just drive it like that for a few days? It's on the side of the transaxle and is high up enough where it isn't submerged in fluid. All it does besides act as a fill location, is stop fluid from coming out if it splashes up against it.

Thanks.
 
Joined
Jan 22, 2011
Messages
7,918
If it is just a fill hole, you should be fine until you get the appropriate washer. I would slide under the car just to inspect after the first run. You could just buy a nylon washer of the correct size which is what I would do without any problems.
 
Joined
Dec 6, 2019
Messages
933
Location
South
That slow trickle could go on for days. Use brake clean and blast the area. Wipe with lint free cloth, quickly push the pan and gasket against the trans mating service, and loosely secure the bolts. Torque to spec in a center out-crisscross pattern. Spray the area again with brake clean to remove any fluid that did leak past and your done. That small fluid trickle won’t set you up for a leak. Those rubber gaskets are great.
 

Frankws6

Thread starter
Joined
Nov 27, 2017
Messages
27
Location
Massachusetts
Thanks guys for the help. It was next to impossible to wait for it to stop so I just wiped it down and moved as quickly as I could to keep it from being too wet. It was just a spot on it. So far no leaks and I'll keep checking for leaks in the following days. But overall, I'm pretty confident I'll have 0 leaks. Now for the bad news:

I was absent minded and realized I installed the pan without reinstalling the two little magnets used to catch metal inside it. I was shocked as to how little metal the magnets collected over 140,000 miles. They were lightly coated. This is a great sign to state the obvious. It was a pain to remove and reinstall and unless it is utterly important, I'd rather wait until this summer to bother dropping the pan and reinstalling the little magnets.
 

CleanSump

Site Donor 2022
Joined
Dec 13, 2019
Messages
1,050
What the others have said re the rubber gasket. If it was a cork/rubber flat cut gasket you'd need the surfaces absolutely dry.
The all rubber designs compress far more and don't need a perfectly dry surface to seal. Just do your best to wipe the case mating surface off and put the pan up quickly to minimize spread and drip.
Torque by the book and you'll be fine.
 
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