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Rear Differential

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I have run into a problem with my Boss with my rear differential leaking. I was wondering if this is a common problem? Has anyone else had this problem?
 
If the leak is through the vent valve, then yes.

If you search, a couple of informative threads should pop up. I'd link them, but I'm feeling lazy right now 8)

Here's a quick explanation of what occurs, which you may already know. When your fluid heats up, it expands and pressure builds up in the diff, which then gets spit out through the vent valve on your diff cover (vent valve on diff cover for boss, on axle tube for GT non-track pack).

People who track their cars usually add expansion tanks to alleviate this problem. Ford has a TSB that adds a small rubber, turkey baster looking, expansion chamber with a plastic vent valve on the top. This has proven to be insufficient during tracking, and some have melted the plastic vent valve on the turkey baster (contact with exhaust).

Last year, I needed a last minute expansion tank before hitting the track, so I ended up making a horrible looking one using a fuel filter, which I got the idea from a fellow member here.

Hope this helps you get started :p. If your leak isn't from the vent valve, then you need to investigate a bit.
 

Grant 302

basic and well known psychic
There's also a good chance that it was overfilled from the factory. My GT was overfilled a little, even after leaking all over my axle tube. No leaking on my Boss.
 
F.D. Sako said:
If the leak is through the vent valve, then yes.

If you search, a couple of informative threads should pop up. I'd link them, but I'm feeling lazy right now 8)

Here's a quick explanation of what occurs, which you may already know. When your fluid heats up, it expands and pressure builds up in the diff, which then gets spit out through the vent valve on your diff cover (vent valve on diff cover for boss, on axle tube for GT non-track pack).

People who track their cars usually add expansion tanks to alleviate this problem. Ford has a TSB that adds a small rubber, turkey baster looking, expansion chamber with a plastic vent valve on the top. This has proven to be insufficient during tracking, and some have melted the plastic vent valve on the turkey baster (contact with exhaust).

Last year, I needed a last minute expansion tank before hitting the track, so I ended up making a horrible looking one using a fuel filter, which I got the idea from a fellow member here.

Hope this helps you get started :p. If your leak isn't from the vent valve, then you need to investigate a bit.

Thank you for the information. It is not the valve so I took it to the dealer so they can figure it out and fix it. There is so much I need to learn about this car.
 
Grant 302 said:
There's also a good chance that it was overfilled from the factory. My GT was overfilled a little, even after leaking all over my axle tube. No leaking on my Boss.

I am really hoping that is all it is. It will be at the dealer until fixed. I am going to go nuts without my car.
 

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