86 Marathon Gas - Differential

[Den17296]

I had a leak in my diifferential and it was coming from the rear pinion. I popped the rubber plug and it was almost an explosion of gear fluid all over me. As got the new pinion seal I'm starting to realize that the rear end has no vent tube. Probably why it might have been leaking and why it exploded on me when I popped the rubber seal.

I'm fairly confident it should have a a vent, right?
Also is the fluid level the top of the rubber plug?
Regular gear oil?

https://imgur.com/a/zb7jnhF

Thanks for any feedback. Been searching for a while and can't find anything.

[Dabble Inn]

I would expect it to have a vent but I really don't think it does, not completely sure about that.......

The book says to use Chevron 200-30 gear lube, not even sure if that's still available but I've been using the 75-90 for 20 years now with no problem........

The bottom of the rubber plug/fill hole is the full mark.

[Den17296]

Originally Posted by Dabble Inn

I would expect it to have a vent but I really don't think it does, not completely sure about that.......

The book says to use Chevron 200-30 gear lube, not even sure if that's still available but I've been using the 75-90 for 20 years now with no problem........

The bottom of the rubber plug/fill hole is the full mark.

Thanks Dabble Inn, it’s weird can’t find a darn pic anywhere.

[Leon willis]

They don’t have vents and P.S. if you are going to work on the diff just remove the axle it’s 6 bolts and the belt and it’s out it is a massive pain working on it in the cart because it’s so pushed back and low ask my back how I know this

[Dabble Inn]

If it's just the pinion seal there's no way I would go to all that extra work of removing the axle lolol, that'd be like pulling an engine to change the spark plugs Just not worth it ffs........

Sometimes in mechanical repair you just have to put up with the awkwardness and get it done, I wish everything I've ever worked on was laying on the bench with me sitting in a chair

[Den17296]

Originally Posted by Leon willis

They don’t have vents and P.S. if you are going to work on the diff just remove the axle it’s 6 bolts and the belt and it’s out it is a massive pain working on it in the cart because it’s so pushed back and low ask my back how I know this

Leon, luckily I have lift in my garage that makes life a lot easier. A little overkill but it works. Crazy they don’t have vents. Never seen a diff without one. Maybe the last owner way overfilled it and it gushed out like it was under pressure. The pinion seal was also past gave and sunk in by 1/8”. Maybe that’s why it leaked, we shall see 😬