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Rear Girdle

Sesshomurai

Has anyone put this girdle on?
http://www.lethalperformance.com/2012-2013-boss-mustang-302/driveline/rear-end-girdles/ford-racing-mustang-low-profile-8-8-axle-girdle.html

My understanding is the factory girdle does not have a drain plug and has to be (partially) removed to drain and then siliconed back on before refill.

With the above girdle, it seems it has a drain and fill plug holes. So I can refill it without removing it, correct?
 
Pete has that one. I added drain and fill plugs to mine.

P1020819.jpg
 

Sesshomurai

So you don't replace the silicone seal or remove it between fluid changes, right?
 
I was thinking about installing drain and fill plugs in my factory cover, but the problem with that and all other aftermarket covers with drains is that you never get all the oil out of the diff case. When taking off the cover, there is always a small amount (probably 2-4+ tablespoons) of gear oil left in the bottom of the differential case. You end up using a shop rag to remove the remaining oil, and metal filings if there is any. The worst part of removing the factory cover to change the oil is cleaning the old RTV off the cover and the housing. The problem with removing a girdle cover to change the oil would be that you would have to loosen the girdle screws and reset them after re-installing the cover. Might be a pain?
 
darreng505 said:
Has anyone put this girdle on?
http://www.lethalperformance.com/2012-2013-boss-mustang-302/driveline/rear-end-girdles/ford-racing-mustang-low-profile-8-8-axle-girdle.html

My understanding is the factory girdle does not have a drain plug and has to be (partially) removed to drain and then siliconed back on before refill.

With the above girdle, it seems it has a drain and fill plug holes. So I can refill it without removing it, correct?

Does not appear to have a breather at the top. Boss tube breathers are pinched shut iirc, so you would want to open one of the tube breathers (assuming you didn't already for a turkey baster).
 
I replaced mine with the 2013 cover, which has a drain hole and magnetic plug.

The fill hole is on the front of the Diff, the top rear hole is for a diff cooler, but is also useful for filling and has an additional magnetic plug for picking up filings - just don't use this to measure fill capacity or you will overfill the axle!
 

PeteInCT

#LS-378 - So many Porsche's, so little time....
Moderator
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Connecticut
The benefit of this is it has adjustablev support for the bearing caps. Helps extend rear diff life. I change fluid enough that I'm not too worried about small amounts of residual fluid and and Rick said you can get it out. I use the vent port on the axle for my JLT fluid reservoir. Works like a charm.
 
So, is there a durability issue with the 8.8" rear end? How do they hold up to moderate-to-heavy track use? For racing or heavy track day use I'd think you'd want to add a diff cooler.
 

PeteInCT

#LS-378 - So many Porsche's, so little time....
Moderator
2,848
14
Connecticut
There are no durability issues I am aware of with the Torsen rear diff. I track my car frequently and drive it hard - I have had no issues other than rear diff fluid 'blowout'. There are a number of topics related to the rear diff:

1) Fluid Overflow 'blowout': If you track the car and drive it the way it's meant to be driven you probably need a JLT overflow reservoir. The TSB 'Turkey Baster' solution offered by Ford does not work - a number of us here on the forum have proven that. Even Redline lightweight shockproof tends to foam up and find it's way out of the stock rear diff vents. This is related only partially to rear diff fluid temp I believe. Needing the reservoir, IMO, doesn't necessarily mean you have a rear diff temp issue.

2) Coolers: the 302S and 302R have an integrated rear diff cooler I believe. Rehagan offers a very nice system but it's pricey (this may be the one in the 302S/302R, I am not sure). Even for heavy HPDE use I don't see this as a 'must have' for the Boss as long as you have the expansion tank. It obviously can't hurt the rear end to have it, but I've been reluctant to go that far since it also adds more potential points of failure to the rear diff design (more hoses, electric pump, etc.)

3) Rear Girdle: The rear girdle we are discussing has the adjustable bearing cap support feature (spec says to set it to 10 ft/lbs). I believe this is the rear girdle used in the 302S/302R but am not 100% sure on that. In any event, I like the integrated drain plug and the fact that it adds adjustable support to the bearing caps, theoretically extending the overall life of the rear diff. I have not seen any reports of issues with the rear diff bearings on cars that are tracked heavily.
 
I am also looking at replacing the Girdle (diff cover) with the Ford Racing one for the same reason. So far I have found that Levitttown Ford Supercenter has the best pricing.

http://www.levittownfordsupercenter.com/oemparts.php?partstr=123/M4033G2.html
 

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