Fluid Level in Diff

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WarrenD
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Fluid Level in Diff

Post by WarrenD »

I have the CD on order (since last week so should be here soon?) but as I'm headed for a show in the next few days, I'm doing the prep now. I checked the fluid level in the rear diff and it's about 3/8" below the bottom of the fill plug hole. Is this correct or should it be level with the fill hole? Truck is on level garage floor and I know the pinion seal has been leaking, so I'm thinking I should add some but wanted to check first.
Thanks in advance, as I learn stuff, I will pay it back.
Chuck
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Re: Fluid Level in Diff

Post by Chuck »

The gear lube doesn't have to be running out of the fill hole.A" little" below is ok. That diff. lube was just changed in July when I did the the rear bearings and seals.
Chuck
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Re: Fluid Level in Diff

Post by WarrenD »

Ok, Thanks "Chuck"
MSeriesRebuild
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Re: Fluid Level in Diff

Post by MSeriesRebuild »

This reply may be too little too late, as I haven't been to this site in a few days; but if the level is down and you know the pinion seal is leaking; the smart thing to do is fill it up to the plug opening, and carry some extra oil along on the trip. In a unit that is not leaking, a little below check plug level is just fine, but you never know when the leak could get worse while driving. Keep a close check on the level, and get the leak repaired properly asap. Taking chances with a diff just can't be considered wise, it will cost more to rebuild one completely than any other single unit on the truck.
Charles Talbert
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WarrenD
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Re: Fluid Level in Diff

Post by WarrenD »

Thanks Charles. You make a good point.
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