75W140 Gear Oil

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Crabman

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Denver Colorado
Has anyone used 75W140 gear oil in place of 75W90? If so were there any benefits or problems? I am having input shaft bearing noise (moderate) and was wondering if the 75W140 might make it quieter.
Thanks for any response!
 
Crabman said:
Has anyone used 75W140 gear oil in place of 75W90? If so were there any benefits or problems? I am having input shaft bearing noise (moderate) and was wondering if the 75W140 might make it quieter.
Thanks for any response!
Click to expand...

I've been running non-synthetic Valvoline 75w-140 for about three years...since the reargear.

Just recently moved to synthetic last month. Chose this product over Redline due to the lower cost...after reading from folks in BOTOG that Redline isn't necessary.
 
Crabman said:
Has anyone used 75W140 gear oil in place of 75W90? If so were there any benefits or problems?
Click to expand...

You will be fine running the heavier weight. It might use a little extra fuel, nothing significant, and it can help muffle noises, but that is just a band-aid. If you are having problems, they will continue to get worse.
 
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@Crabman like the other guys have said, you should clarify if you're talking about axle gears or manual transmission. If axle, my answer above applies. If you're talking manual transmission, then you run ATF/MTF and NOT a gear oil.
 
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For a manual would you use ATF? Is that that same as the MS 9224 manual transmission fluid? I thought they were different.
 
The trans specs a GL-4 75W-90.

While 75W-140 wouldn't hurt anything, you probably aren't going to find a GL-4 version of it. The GL-5 version, which is what you'll find, is not safe for the yellow metals in the trans unless you can find a version that says it's yellow metal safe.

Need to fill out your profile with your Jeep info.

Jeep now allows 10W-30 synthetic motor oil instead of 75W-90 GL-4 as well.

I'm currently running 0W-40 syn in my YJ's AX-15 and no issues.
 
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