Correct front differential oil level

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Peteda2
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Correct front differential oil level

Unread post by Peteda2 » June 20th, 2020, 3:04 pm

Hi all, I have the following question regarding correct differential oil level: I opened for the first time the front differential oil fill plug (of a recently acquired truck) on the side of the differential to check if the oil level is correct because I would find small amounts leaking when the truck was parked for a while. As a soon as I loosened the plug gear oil started coming out feeling like I am loosening a drain plug not a fill and level plug. My question: Is the differential overfilled or I am doing something wrong? I was of the impression that the right level should be with the gear oil flush with the bottom of the fill plug threads. The truck was on level ground when I tried this, and differentials were parallel to the ground.
Any advice will be much appreciated.
Thanks
:?

Mark
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Re: Correct front differential oil level

Unread post by Mark » June 20th, 2020, 3:19 pm

The plug is horizontal so the gear oil is level/just starts to come out of the hole
mark


1968 m274A5
1960 m151
1981 m151A2
1964 m416
1971 m416

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rickf
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Re: Correct front differential oil level

Unread post by rickf » June 20th, 2020, 3:28 pm

What Mark said, if the differentials were cold then the oil level should be even with the bottom of the fill hole. You can put a pan under there and just take out the fill plug and let it drain down to the correct level and put the plug back in.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

Peteda2
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Re: Correct front differential oil level

Unread post by Peteda2 » June 20th, 2020, 8:47 pm

Thanks for the quick response. I will try that!!

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m3a1
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Re: Correct front differential oil level

Unread post by m3a1 » June 20th, 2020, 10:02 pm

Keep in mind someone may have filled it on an incline, or even with the differential out of the vehicle.

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rickf
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Re: Correct front differential oil level

Unread post by rickf » June 21st, 2020, 9:07 am

Or overfilled it to compensate for the leak so keep an eye on the leak. I had a seal blow out completely on a ride and lost all the fluid while driving. Yea, it was smoking when I got home!
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

Peteda2
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Re: Correct front differential oil level

Unread post by Peteda2 » June 21st, 2020, 9:52 pm

Thanks for the responses. I will keep an eye on it. This is an army depot overhauled differential with an overhaul tag on it. Looks pretty new. Perhaps it was filled off the vehicle ?

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m3a1
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Re: Correct front differential oil level

Unread post by m3a1 » June 21st, 2020, 11:31 pm

That is entirely possible

Mark
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Re: Correct front differential oil level

Unread post by Mark » June 21st, 2020, 11:37 pm

My faded memory says the differential when mounted on the body had rubber pads in between metal mounts?
mark


1968 m274A5
1960 m151
1981 m151A2
1964 m416
1971 m416

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rickf
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Re: Correct front differential oil level

Unread post by rickf » June 22nd, 2020, 8:38 am

No rubber pads, that was an attempt by owners to cut down on noise and it usually ended up causing damage from the differential moving around on the rubber and hogging out the bolt holes. Nobody seems to realize that it is not so simple as that, you also need to isolate the mounting bolts completely from touching any metal, Not going to happen without drilling something for clearance. It just was not designed for that.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

Mark
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Re: Correct front differential oil level

Unread post by Mark » June 22nd, 2020, 10:34 am

Thanks for refreshing the memory
mark


1968 m274A5
1960 m151
1981 m151A2
1964 m416
1971 m416

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