M35a2 front differential leaking

[mbfd592]

I just purchased a 1970 M35a2 from the firehouse I am a member at. It was used as a high water rescue truck so my first action is going to change all the fluids. I took it for a ride the other day and noticed I have gear oil coming from where the front drive shaft comes into the differential (top loader I believe is the correct name for it). Also is leaking out of the front where another shaft would be connected. I believe they are pinion seals. The gear oil is milky so I know water has made it in there. What would be the best way flush out all the contaminated oil when I service it? Also what else should I look for? Trying to get all the parts I need so when there is a break in the weather I can start working on it. Thank you in advance.

 

[NDT]

Yes those are pinion seals, available from numerous sources.
To flush, take the truck for a drive to get the milkshake good and agitated, then drain, then refill with diesel, then low speed drive, then drain and repeat if you still detect water.

 

[Mullaney]

I just purchased a 1970 M35a2 from the firehouse I am a member at. It was used as a high water rescue truck so my first action is going to change all the fluids. I took it for a ride the other day and noticed I have gear oil coming from where the front drive shaft comes into the differential (top loader I believe is the correct name for it). Also is leaking out of the front where another shaft would be connected. I believe they are pinion seals. The gear oil is milky so I know water has made it in there. What would be the best way flush out all the contaminated oil when I service it? Also what else should I look for? Trying to get all the parts I need so when there is a break in the weather I can start working on it. Thank you in advance.

.
Welcome to the Outfit!

Like @NDT mentioned, the pinion seals are leaking and the milky look in the oil is bad news. Definitely want to drain it. The diesel in there on a refill will help wash out the milk oil. Assuming that if the front is milky - the other two axles will be the same. You may want to drain the transfer case and transmission too.

You may want to download the Technical Manuals (TM's) so you can find part numbers. Chances are that you can remove the seals and match them up with standard seals.

 

[HDN]

Also check the axle vent, and clean or replace as needed. You should probably check all the vents. The same part is used on the military jeeps too.

 

[mbfd592]

Yes those are pinion seals, available from numerous sources.
To flush, take the truck for a drive to get the milkshake good and agitated, then drain, then refill with diesel, then low speed drive, then drain and repeat if you still detect water.

Thank you

 

[mbfd592]

.
Welcome to the Outfit!

Like @NDT mentioned, the pinion seals are leaking and the milky look in the oil is bad news. Definitely want to drain it. The diesel in there on a refill will help wash out the milk oil. Assuming that if the front is milky - the other two axles will be the same. You may want to drain the transfer case and transmission too.

You may want to download the Technical Manuals (TM's) so you can find part numbers. Chances are that you can remove the seals and match them up with standard seals.

Thank you. Plan on changing all the fluids. Definitely will download the manual

 

[mbfd592]

Also check the axle vent, and clean or replace as needed. You should probably check all the vents. The same part is used on the military jeeps too.

Will do. Thank you