Rear diff puking from vent hole. Suggestions

[RedVenom48]

Hi all. Ok so I decided to upgrade my rear diff fluid from dealer fill gear oil to Redline Heavy Shockproof oil.

Removed cover, cleared as much old fluid out as possible, cleaned cover and diff. Reseal cover with Ford sealer and let dry. Added 4 oz of Ford friction modifier, and proceeded to fill the diff with about 2.4 qts of Shockproof. Filled till it comes out fill hole, let it come to a trickle and reinstalled the plug. (BTW, the way this stuff coats gears/metal is insane!)

Drove around a bit and the next day notice a gear oil smell. Sure enough leaking from vent. Cleaned off and drive again for a few days. Recheck, still leaking from vent Grrrr.....

Clean off fluid, pull onto alignment rack and remove fill plug to inspect level at ride height. Notice an air noise, like pressure let out from a tire.... Plug all the way out and not trickle coming out.... Reinstall plug and rechecked tonight: fluid leaking AGAIN from diff cover vent.

Do I have an issue with my diff vent? If left uncorrected could I have a pinion bearing seal blow out? WILL IT EVER STOP LEAKING?!?!?!

Any tips or suggestions appreciated!

 

[usmc_mustang]

This will solve the leaking
http://www.lethalperformance.com/sh...helby-5-8-l-gt500/driveline-1/axle-reservoirs

 

[Tob]

You are indeed having an issue with your vent. I'd recommend something along the lines of the above as opposed to a new factory vent. The OEM system was inadequate, especially if the car is used on a road course.

 

[bFoxGt500]

Not to be the "cheap guy" but after my first Texas mile in 2011, I noticed diff fluid along my axle that leaked through the factory vent (mine's an '08). Brought it to the dealer and they replaced the vent with a small rubber reservoir that looks like the bulb of a turkey baster. Has worked great - and I do multiple road course events. I do like the axle reservoirs linked above, but I thought the turkey baster approach was a pretty simple and effective option.

 

[Catmonkey]

As in the vent hole on top of the finned vent cover? This is normal street driving? There should have been a baffle on inside of the cover to keep fluid from climbing up the vent. Do you recall see it? If it's the fluid is expanding that easily, I think I drain it and try something else.

 

[RedVenom48]

This will solve the leaking
http://www.lethalperformance.com/sh...helby-5-8-l-gt500/driveline-1/axle-reservoirs

Thank you for the link! Will be ordering the JLT ASAP.

Tob: For now, after a little research, Im going to try this kit intended for Mustangs and GTs: DR3Z-4022-A If it doesnt fit the threads, some ghetto rigging will commence.

Catmonkey: baffle was in place. I think the vent is failing/ has failed. Combined with a much more robust and thick gear oil like shockproof it pukes out baffle or not.

 

[Tob]

Interesting assembly.

http://www.svtperformance.com/forum...quot-new-quot-solution-to-the-leaky-axle-vent

 

[einehund]

I had this issue on the Autobahn with the constant high speeds. The passenger side of the axel always looked like some oil giant threw up. The expansion tanks shown above did the trick.

 

[Robert M]

Interesting assembly.

http://www.svtperformance.com/forum...quot-new-quot-solution-to-the-leaky-axle-vent

Tob - In the link above, the vent appears to be plastic on the end of that extension hose, do they give problems?

Is a plastic vent valve something that Ford has gone to? Would the oem metal vent from an axle tube location work better in this area where there is heat? OR is this what the newer cars already have from the factory?

R

 

[RedVenom48]

Remote vent seems to be a better idea, IMO. PIcs soon of my "setup".

 

[Robert M]

Remote vent seems to be a better idea, IMO. PIcs soon of my "setup".

I did a remote with reservoir also when I had my 8.8 out for restoration..........

R

 

[Tob]

Robert, I can't say that the metal vent would perform better than the plastic one in the linked extension assembly - I have zero data with respect to that specific comparison. I find it a bit intriguing that the S197 axle assemblies seem to suffer from this malady more than any other than I can think of. The factory is obviously struggling with the issue but no doubt that is in part to their unwillingness to address it with a substantial fix. Allowing the fluid to exit the assembly, cool, and return seems to be the most viable solution short of a cooler, etc.

 

[RedVenom48]

Ghetto rigged!



So here is my poor mans creation. I took the DR3Z-4022-A kit hose and traced a hole around the cap of a used and cleaned bottle of brake fluid. Using a Dremel I cut the hole and installed the hose right on through. Sealed it up with Ford diff seal maker and let it dry.

I then installed the included nipple to replace the vent. Once the hose assembly was dry I tried a few different positions and found I could ziptie the bottle to the upper control arm. As the diff and the arm will always be stationary relative to each other and the ground, I though this to be the best point to mount it.

The bottle as it is located doesnt move, and clears the body as the diff assy articulates. Raced it at an event last night and NO gear oil touched the ground. I poked a few vent holes on the other side of the bottle and did observe a little seepage. This tells me that there is a lot of fluid that gets flung up out of these diffs. I may make a modified bottle with a vent hole and hose and eliminate any fluid escaping. If so pics will follow.

I know that my assembly will not allow the fluid to drain back into the diff. Honestly, not worried about it staying in the bottle. Whats lost is not even really that much and I assume whats getting to the bottle isnt even nearly as much as what came out with the vent on the diff cover itself. In about a month Ill remove the bottle and see whats actually in there.

Hooray! More money for go fast parts and I wont slick down the track!

 

[Robert M]

View attachment 50572

So here is my poor mans creation. I took the DR3Z-4022-A kit hose and traced a hole around the cap of a used and cleaned bottle of brake fluid. Using a Dremel I cut the hole and installed the hose right on through. Sealed it up with Ford diff seal maker and let it dry.

I then installed the included nipple to replace the vent. Once the hose assembly was dry I tried a few different positions and found I could ziptie the bottle to the upper control arm. As the diff and the arm will always be stationary relative to each other and the ground, I though this to be the best point to mount it.

The bottle as it is located doesnt move, and clears the body as the diff assy articulates. Raced it at an event last night and NO gear oil touched the ground. I poked a few vent holes on the other side of the bottle and did observe a little seepage. This tells me that there is a lot of fluid that gets flung up out of these diffs. I may make a modified bottle with a vent hole and hose and eliminate any fluid escaping. If so pics will follow.

I know that my assembly will not allow the fluid to drain back into the diff. Honestly, not worried about it staying in the bottle. Whats lost is not even really that much and I assume whats getting to the bottle isnt even nearly as much as what came out with the vent on the diff cover itself. In about a month Ill remove the bottle and see whats actually in there.

Hooray! More money for go fast parts and I wont slick down the track!

I agree with you that leaks do SUCK!!

Let us know how much fluid actually makes it to that bottle when you check it again.








R

 

[tomshep]

Not sure what Ford's logic was in moving the vent from the axle tube to the top of that cover. That is a piss poor location. The rotation of the ring gear is slinging lube right up at the vent and the windage will cause the lube to gather at the top of the housing. That is just pushing it right out of the vent. By extending the hose upward that is going to help greatly by making it more difficult to push the lube up that far vertically and then over the top of the hose arch into the catch can. Job well done. I doubt you will get much fluid in there.

Tom