Rear end is leaking....yay.....

[Grimster]

Noticed some oil on my garage floor. Got up underneath the car and sure enough, the rear diff cover is leaking. Sucks.

I didn't notice any kind of cracks or anything, so I believe the cover is still intact and not "broken", but what should my next step be? I found the fill plug, so I'll be refilling it this evening to see exactly how low it is. There are quite a few drops of oil on my garage floor, some new some old, so it's been leaking slightly for a while it seems.

I have a brand new black Billetflow IRS Brace that I haven't gotten around to installing yet. Heck it is still in the box from Billetflow. Should I just remove and reseal the cover (maybe lube locker gasket?) and put the brace on it? Or since Im going to so much trouble to reseal it anyway, just swap it out for the LPW Differential cover?

If that's the route I should take, anyone want to buy a brand new IRS Brace to help fund this? It's well past the 30 day return for Lethal to take it back, and I think they'd charge a restocking fee anyway.

Here is a nice photo I snapped with my phone...

 

[caveeagle]

I am in the same boat! I just noticed the leak when I had the car up in the are replacing the clutch.

I am ordereing either the LPW or the FR diff cover. Also putting in MM diff bushings while I am in there. I think the loose bushings is what made my stock covers flex and leak.

I think its kind of odd that my irs cross member appears to be tight, but there is still a lot of play in the two front rubber (stock) bushings. My car has ~90k miles, but I would not expect the stock rubber to be totally trashed already.

Does yours have any play in it?

 

[ac427cobra]

Noticed some oil on my garage floor. Got up underneath the car and sure enough, the rear diff cover is leaking. Sucks.

I didn't notice any kind of cracks or anything, so I believe the cover is still intact and not "broken", but what should my next step be? I found the fill plug, so I'll be refilling it this evening to see exactly how low it is. There are quite a few drops of oil on my garage floor, some new some old, so it's been leaking slightly for a while it seems.

I have a brand new black Billetflow IRS Brace that I haven't gotten around to installing yet. Heck it is still in the box from Billetflow. Should I just remove and reseal the cover (maybe lube locker gasket?) and put the brace on it? Or since Im going to so much trouble to reseal it anyway, just swap it out for the LPW Differential cover?

If that's the route I should take, anyone want to buy a brand new IRS Brace to help fund this? It's well past the 30 day return for Lethal to take it back, and I think they'd charge a restocking fee anyway.

Here is a nice photo I snapped with my phone...

This is something every Cobra owner experiences with OEM rubber or aftermarket poly bushings. That is until they stabilize their differential housing.

FTBR Frequently Asked Questions

For more information regarding the IRS and what you should be doing as an owner see the full FAQ on our site:

FTBR Frequently Asked Questions

We have an entire web site dedicated to the Cobra Independent Rear Suspension and have solved thousands of problems for Cobra owners.

Seeing you already have the brace, I'd put the brace on and reseal your rear cover.

When you put the IRS back in the car you're going to want to upgrade your front and rear diff mounts to the FT 1200 and FT 1300 found on our site. If you currently have a driveline vibe, I would seriously consider upgrading to the FT 1400 Delrin isolated rear lowering diff mount we offer in place of the FT 1300.

:thumbsup::coolman::beer:

 

[01cobravortech]

This is something every Cobra owner experiences with OEM rubber or aftermarket poly bushings. That is until they stabilize their differential housing.

FTBR Frequently Asked Questions

For more information regarding the IRS and what you should be doing as an owner see the full FAQ on our site:

FTBR Frequently Asked Questions

We have an entire web site dedicated to the Cobra Independent Rear Suspension and have solved thousands of problems for Cobra owners.

Seeing you already have the brace, I'd put the brace on and reseal your rear cover.

When you put the IRS back in the car you're going to want to upgrade your front and rear diff mounts to the FT 1200 and FT 1300 found on our site. If you currently have a driveline vibe, I would seriously consider upgrading to the FT 1400 Delrin isolated rear lowering diff mount we offer in place of the FT 1300.

:thumbsup::coolman::beer:

This is an interesting post Bruce. Prior to installing your alum diff bushings, I had resealed the diff cover 3 times (and had the BF brace on there all 3 times) and it still would leak. Since your bushings went in about 2 months ago, my cover hasn't leaked. :thumbsup:

 

[ac427cobra]

This is an interesting post Bruce. Prior to installing your alum diff bushings, I had resealed the diff cover 3 times (and had the BF brace on there all 3 times) and it still would leak. Since your bushings went in about 2 months ago, my cover hasn't leaked. :thumbsup:

Well.......... the good news is, your brace saved you from cracking your rear cover. :thumbsup:

The bad news is, with an unstabilized differential housing, you're going to get real good at removing the rear diff cover an resealing it! ;-)

 

[Tractionless1]

Throw the brace in the trash and do an LPW cover as you'll be there in the disassembly stage to do so. My rear was resealed 8k miles ago with a Steeda brace and started leaking a few months ago. BTW only 4 track passes in that amount of time.

 

[caveeagle]

Anyone have feedback on the LPW diff cover compared to the Ford Racing cover?

 

[ac427cobra]

Anyone have feedback on the LPW diff cover compared to the Ford Racing cover?

I prefer the Ford Racing cover for two reasons. #1, it has a tapped location for a return line for a diff cooler. #2, our Delrin isolated rear diff lowering mount is machined to work with the Ford cover.

The Fore and LPW covers will not work with rear lowering mounts without extensive modification to the mount and the cover.

FWIW

:thumbsup::coolman::beer:

 

[Jimmysidecarr]

I prefer the Ford Racing cover for two reasons. #1, it has a tapped location for a return line for a diff cooler. #2, our Delrin isolated rear diff lowering mount is machined to work with the Ford cover.

The Fore and LPW covers will not work with rear lowering mounts without extensive modification to the mount and the cover.

FWIW

:thumbsup::coolman::beer:

And #3 the rear lowering mounts are highly beneficial in facilitating the correct pinion angle, which when done properly as per Bruce's excellent directions bushings and shims, virtually eliminates "the dreaded Cobra high speed vibe"!:beer::rockon:

 

[Grimster]

Bruce - I'll be reading your website and then shooting you an email for sure. There is a chance your website will answer ALL of my questions....but Im not going to give myself that much credit of being able to digest it all before I place an order. lol.

Thanks everyone for their input. I'll definitely be updating this thread with how I push forward

 

[01cobravortech]

I prefer the Ford Racing cover for two reasons. #1, it has a tapped location for a return line for a diff cooler. #2, our Delrin isolated rear diff lowering mount is machined to work with the Ford cover.

The Fore and LPW covers will not work with rear lowering mounts without extensive modification to the mount and the cover.

FWIW

:thumbsup::coolman::beer:

Hmm...I wasn't aware that Ford Racing had given us an alternative.

Is this the cover you're referring to?

1999-04 Mustang Ford Racing 8.8" Irs Rear Differential Girdle, M-4033-G3 at LRS - Same Day Shipping!

 

[ac427cobra]

Hmm...I wasn't aware that Ford Racing had given us an alternative.

Is this the cover you're referring to?

1999-04 Mustang Ford Racing 8.8" Irs Rear Differential Girdle, M-4033-G3 at LRS - Same Day Shipping!

Yes................but I prefer THIS vendor:

Full Tilt Boogie Racing Shopping Cart

FT 1350

:thumbsup::coolman::beer:

 

[01cobravortech]

Yes................but I prefer THIS vendor:

Full Tilt Boogie Racing Shopping Cart

FT 1350

:thumbsup::coolman::beer:

Sweet! I need to check your site more often as I didn't even know you sold it. And I just have to have FT 1401 ! Keep up the good work with your new products. That one is going on my list to Santa.

 

[Tractionless1]

Stock pininon angle here with LPW cover, Maximum poly bushings and have never had any vibe.

 

[blwn03sonic]

Is removing and reinstalling the diff cover on an IRS hard to do. Mine is leaking too.

 

[caveeagle]

It seems that the correct way is to pull the spindles / half-shafts / tie rods and drop the diff to gete good access to remove the cover.

There was a poster here that was able to 'sneak' it in by removing the irs cross-member and pushing the unit fwd just enough to get the cover off. I did not feel comfortable with that method and already had the cat-backs removed.

I am only 1/2 way through this, but I would rate it as a 6/10 for difficulty.

 

[SVT_Troy]

I just removed my cover to inspect the gears. I didn't remove the diff but I did support the diff with a tranny jack while I removed the front diff brace to allow me to move the diff around to remove the cover. The hardest part was reinstalling the cover without smearing the sealant everywhere. Like I previously said I had a tranny jack to support the diff so it wasn't just hanging by the axles but it made it easier moving/keeping the diff in position. When reinstalling the cover I had someone to help me Pull the diff back while I carefully slide the cover back in without messing up the sealant. Next time I remove it I'm going with the fort racing cover and ftbr bushings

 

[Tractionless1]

I just removed my cover to inspect the gears. I didn't remove the diff but I did support the diff with a tranny jack while I removed the front diff brace to allow me to move the diff around to remove the cover. The hardest part was reinstalling the cover without smearing the sealant everywhere. Like I previously said I had a tranny jack to support the diff so it wasn't just hanging by the axles but it made it easier moving/keeping the diff in position. When reinstalling the cover I had someone to help me Pull the diff back while I carefully slide the cover back in without messing up the sealant. Next time I remove it I'm going with the fort racing cover and ftbr bushings

Why not use a lubelocker gasket while you were there?

 

[SWAMPMODULAR]

I prefer the Ford Racing cover for two reasons. #1, it has a tapped location for a return line for a diff cooler. #2, our Delrin isolated rear diff lowering mount is machined to work with the Ford cover.

The Fore and LPW covers will not work with rear lowering mounts without extensive modification to the mount and the cover.

FWIW

:thumbsup::coolman::beer:

Well that sucks because your kit was next on my list and I have the LPW. :shrug:

 

[SVT_Troy]

Why not use a lubelocker gasket while you were there?

I just saw this thread the day I posted so I had no idea about the gasket at the time of doing mine. I will be ordering one soon and just keepin it around for he next time I take it off. Hopefully it doesn't leak now and the next time I take it off will be when I do the Ford Racing cover and ftbr bushing kit all at once.