Mustang 8.8" info please

The ghoul

Forum Member
Looking to swap an 8.8" into my g body.
Im pritty much set on finding one out of a mustang, fox body seems to be 1.25" wider than my stock rear end, unsure on if that changed for the next genneratior or not?
Hopefully I can find one the correct width, with posi, and rear disc brakes...
What I'd like to know (if you all know off the top of your heads)
- what years models came with rear disc and posi
- what are the weak points on it (stuff to change before I swap it in)
- is there a diffrence in width between fox body (86-94?) and the next gen (95-98?)
 
Here is some detailed info on the Fox rear end:
http://1985mustanggt.com/Reference/Rear_Axle_Dimensions_070208.pdf

The '94-'98 rear axle assembly has 0.75" longer axles (1.5" wider total) than the '79-'93 (excluding the '93 Cobra).
The 8.8" housings are the same '86-'98.
The '99-'04 housing is 1.5" wider (.75" per side) and the axles are each 1.5" longer (3" total) than the '79-'93 rear end.
All V8 Mustangs came with the traction lock differential.
5-Lug Rear disc brakes came on the '94-'04 cars.

--Vince
 
- what are the weak points on it (stuff to change before I swap it in)

I believe that all the 8.8s from the years you're looking at came with 28 spline, C-clip axles. Depending on power level, you might want to consider upgrading to 31+ spline. Some people install 9" housing ends to do away with the C-clips (I don't believe you can run disk brakes with C-clip eliminators). Most people have the axle tubes welded to the center too. Another thing to consider is gear ratios- I believe that 3.55s were optional from 99-04. Finally, most people install aftermarket girdles.
 
I researched it more and devised a bit of a "game plan"
The C clip thing does kinda bugger the works tho...
Definetly have to look into the girdle..
-95-02 explorer 4.10 or 3.73 disc rear end $150 at yard.
*note; explorer axle is offset and has no previsions for upper control arms
-moser 31 spline mustang axles $300 ish
-Install/bearing kit $100
-86-93 4bolt open drum mustang 8.8" rear end ($50 Craigslist)
-mustang upper control arm spherical bearings ($100)
-stock g body LCA (I'd box em and toss in poly bushings)
-mustang double adjustable upper control arms (free for me to make)
-mustang u joint $30 autozone
-mustang pinion yoke (free with axle)
-mustang rims (free with axle)

Only complex thing about this swap (other than rebuilding and swapping rear end bits) will be either cutting lower spring perches off the 7.5" and welding them onto the 8.8"
Don't know for sure, but I'm fairly certen I can adapt the explorer ebrake cables, if not inline tube can make you some special...

Seems like a winner to me
 
I believe that all the 8.8s from the years you're looking at came with 28 spline, C-clip axles. Depending on power level, you might want to consider upgrading to 31+ spline. Some people install 9" housing ends to do away with the C-clips (I don't believe you can run disk brakes with C-clip eliminators). Most people have the axle tubes welded to the center too. Another thing to consider is gear ratios- I believe that 3.55s were optional from 99-04. Finally, most people install aftermarket girdles.
Just called up moser;
They reccomended bolt in axles which will require the 9" flanges (their PN 7750) which then would accomidate disc
 
Just called up moser;
They reccomended bolt in axles which will require the 9" flanges (their PN 7750) which then would accomidate disc

I would research the C-clip issue a bit more... Don't forget that you'll need to buy a new posi unit when upgrading to 31 spline. So after reading your posts, it appears that you'll wind up doing a totally custom 8.8" which I think would cost a few thousand dollars to have done professionally. It would be way cheaper to keep an eye out on the Ford sites (Modular Fords, SVTP, the Corral, etc.) for a nice built 8.8" to come up. You could probably get one that is completely upgraded (except perhaps the 9" ends) for around a thousand dollars. You might have to pick up brakes seperately, but they are cheap.
 
I would research the C-clip issue a bit more... Don't forget that you'll need to buy a new posi unit when upgrading to 31 spline. So after reading your posts, it appears that you'll wind up doing a totally custom 8.8" which I think would cost a few thousand dollars to have done professionally. It would be way cheaper to keep an eye out on the Ford sites (Modular Fords, SVTP, the Corral, etc.) for a nice built 8.8" to come up. You could probably get one that is completely upgraded (except perhaps the 9" ends) for around a thousand dollars. You might have to pick up brakes seperately, but they are cheap.
Thanks for the info;
The plan is to use the explorer 31 spline posi diff, ring and pinion (3.73 or 4.10 what ever I find first). To keep it on the cheap as this is just a street/occasional autocross car) I was just going to use the explorer disc setup.

$150 for a compleetly dressed explorer rear end at the local yard.

I was going to leave a stronger ring/pinion and after market diff till down the road (if I decide to push the HP more)

Yeah I'm still very foggy on the c clip, vs bolt in and the differences in housing ends (learning ford rear end as I go).
 
I think there's a guy on MalibuRacing that sells 8.8s that have been modified to fit g-bodies, his name was Monza something or other I'll have to see if I can dig it up.

Not sure on your budget, but you might end up money ahead just looking for an 8.5". If you're just looking for rear discs, 98-02 f-body stuff bolts on the three bolt g-body flange with some minor modifications.

Found the guy on MalibuRacing - monzaz, his web site is http://www.jdrace.com/ My e-mails with him pretty much said a stock 8.8 will fit in, you just need to fab a set of upper control arms.
 
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Oh I see, your plan makes sense! I wouldn't worry about the C-clip issue unless you're looking at a max effort build for drag racing. C-clips hold the axles into the rear, but they're located near the carrier... If you break an axle, there is nothing to keep the wheel from coming off. 9" ends hold the axles at the end, providing safety should you break an axle. Not an issue unless you plan on breaking axles with lots of power and sticky tires. I have been around the Mustang crowd for years and have only seen a few 8.8s with the 9" ends.
 
I think there's a guy on MalibuRacing that sells 8.8s that have been modified to fit g-bodies, his name was Monza something or other I'll have to see if I can dig it up.

Not sure on your budget, but you might end up money ahead just looking for an 8.5". If you're just looking for rear discs, 98-02 f-body stuff bolts on the three bolt g-body flange with some minor modifications.

Found the guy on MalibuRacing - monzaz, his web site is http://www.jdrace.com/ My e-mails with him pretty much said a stock 8.8 will fit in, you just need to fab a set of upper control arms.
Thankyou for tracking him down, I did see that around..

The 8.5" are getting rough to find and there fore are getting expensive.

The issue isn't really installing the 8.8" rear end (basically I could buy a cobra rear axle for $500 and all I'd need is the pinion yoke, mustang u joint, two mustang wheels, mustang adjustable upper control arms and I'd still need to fab lower spring perches; the g-body lower controle arms are the correct size and lenght). But I'd then have a 28 spline, 3.2ish? Ratio with hard miles on the rear diff (assuming from most cobra owners I know) and old bearings


What I'm trying to persue here is the possibility of using the explorer 31 spline 8.8 issues however are the explorer rear end is "offset" the pinion being 2.31" from centerline, and it has no previsions for upper controle arms. But, at this point to swap in the differential/ring and pinion into the fox body rear end case and use the explorer rear discs I'd need custom axles, 9" housing ends, and setup kit...

So with a few hundred dollers more it looks like you could have a 31 spline, (3.73 or 4.10) posi rear end, ss axles, and all brand new bearings and seals...
 
Ok, so I presued another train of thought...
I thought perhapse the 99+ mistangs had different housing ends that would accomidate the 31 spline axles and backing plates for disc... Seems the issue is bearing size.
This link has some good info
http://forums.corral.net/forums/gen...u-run-explorer-axles-fox-i-think-you-can.html

Looking it all over it sees the options to make this work for me would be;
-explorer rear axle with the long side tube/axle swapped for another short tube, 4link kit, narrow the back end and run tubs
-fox body housing, 9" ends, 31 spline explorer diff, moser axles, explorer rear discs
-fox body housing, c clip eliminaters (natorious for leaking), fox rear drums, moser axles, explorer 31 diff
-full stock 28 spline cobra rear end g body spring perches (budget build)
-full offset explorer rear end, upper controle arm mounts, lower spring perches, driveshaft tunnel mod.
Mind you there's more to this but all the options would require the same things to swap them in so I ommitted it.

I must admit I'm really leaning twards the tubbing route, or just full stock offset explorer rear end.
 
I'm curious what you end up with, I'm sure the 7.5 in mine will need to be replaced at some point in it's life. You know, some of the offroad guys I thought built upper control arm mounts that came off the axle tubes (like a bridge up and over the rear diff), maybe you could do something like that with the explorer rear. You'd be able to mount the ears for the upper control arms at the g-body angle as well and not need offset arms.

I always wanted to see if a Cobra IRS could fit back there...
 
I believe that all the 8.8s from the decades you're looking at came with 28 spline, C-clip axles. Based on energy, you might want to consider improving to 31+ spline. Some individuals set up 9" real estate finishes to do away with the C-clips (I don't believe you can run drive braking system with C-clip eliminators). Most individuals have the axle pipes welded to the middle too. Another factor to consider is equipment ratios- I believe that 3.55s were optionally available from 99-04. Lastly, most individuals set up upgraded girdles.

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There is a 9" g body housing on Craigslist right now for 275$
That might be a cheaper way to go
 
Strange and Moser both sell c clip eliminator kits that will go on a factory axle (basically bolt in) and don't have to weld on a 9" end. My nephew just ordered his suspension kit from Base Line Suspension for his 8.8 G body swap.
 
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