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AMC 20 Fluid Level Question of Concern

AMC 20 Fluid Level Question of Concern

Gitzo

Jeeper
Posts
10
Media
1
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Location
Charlotte
Vehicle(s)
1979 Jeep CJ 5
258 w carb
T18 transmission
Just this week I just took ownership of my CJ5 and I am trying to access and prioritize my maintenance. The jeep is parked level in my garage. Today I pulled the fill plug on the Rear AMC20 and the oil came pouring out. I'm positive it needs to be changed and is on my to do list, but would you recommend me pulling the plug again and letting the oil level out?

Estimating I lost about about a cup.

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My only guess is that the last time it was topped off it was prior to the lift-kit or it was up on a lift that allowed the leaf springs to relax and the level was off slightly.

The axle still has the factory TORX bolts holding the cover on.

Thanks!

John
 
Not sure how they got that much fluid in there but yes you can drain until the fluid level is equal to the top of the fill hole. The torx bolts should be replaced with hex bolts, they are a disaster waiting to happen. New hex bolts, a new gasket and fluid is cheap insurance, you can probably do that for around 30 bucks. While the cover is off clean the gears with carb cleaner and inspect the gears for any damage, also not the gear size you have if its not already marked on the outside.
 
other than parking on a big angle, I have no idea how someone would over fill it that much.
I have seen them over full because they were full of water.:eek:
I'd take the cover off like Tin said and see what ya got.
 
other than parking on a big angle, I have no idea how someone would over fill it that much.
I have seen them over full because they were full of water.:eek:
I'd take the cover off like Tin said and see what ya got.

I'm with Old Dog, would pretty much bet it was water mixed in there.

Sent from my SAMSUNG-SGH-I317 using Tapatalk 2
 
I have seen that when an axle has been filled/topped off at a quickie lube type shop it is not unusual to find the differential overfilled. Not sure if this is because of the equipment that is used to move the oil or not but I suspect that may have something to do with it.
 
Thanks Guys. The oil that spilt out was pretty consistent and dark. It didn't show any signs of being milking from water. First action I am going to take is to get a catch pan and let the oil level out. Then from there I'll do my homework and completely change the fluid, gasket, and nuts. I did it once 20 years ago on a CJ8 I owned. I was young and dumb. Taking my time with this one. I'll be rinsing and repeating the process with the front diff, Transfer Case , and Transmission once I start the process.

Gitzo
 

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