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8.8 rear end

  • Thread starter Thread starter dapenberthy
  • Start date Start date Sep 19, 2011
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zookeeper

Founding Member
Aug 25, 2001
3,415
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Rogue River, Oregon
Nov 26, 2011
#21
  • Nov 26, 2011
  • #21
madmike1157 said:
8 or 9" rears are not be hard to find? I guess that all depends on how hard you have to look. Even when you do, you'll probably find a open diff rear that is the wrong width w/ a bazillion miles on it. 8.8's are everywhere, in every junk yard in the US. A 95 GT mustang rear will have disc brakes and 5 lugs (5 on 4.5),will have a T-loc diff and will more than likely be a 3.73 ratio if the donor car had a 5 speed. It will only require cutting the lower control arm mounts off, and welding the spring perches on ( which can be bought brand new for cheap) in order to fit the car. Even in stock 28 spline configuration, a street tire'd car will not hurt it. (Tire spin being the buffer). However If you're gonna race it,28 spline axles are iffy as drag slicks and a the sticky starting line will definitely test them.

But I doubt the "benefit" of removing the street geared center section and swapping a 4-something ratio in place so you can go drag racing and then re-installing that heavy assed center back in on sunday night so you can go to work is truly a benefit. Just get a 5 speed from the same donor car as the rear and you can keep the 3.73's all week long.
Click to expand...
Again, I guess we all live in different areas. I have tried to give away (as in free) a complete '65 8 inch for years that's been in my garage with no takers. But I parted out an '89 Mustang GT last year and was able to easily get $140 out of it's 8.8 rear axle with 2.79 gears. Did '95's really come with 3.73's stock? About your '95 Mustang example: those 5 speeds won't fit in early Mustangs, and even if they did I have never seen on in our local wrecking yards. After waiting for over a year for a T-5 core to show up, I simply bought a whole car for less than the yard owners wanted for a tranny and bellhousing. BTW, I've been looking for one of those cheap (?) T-bird Turbo Coupe rear axles that are supposed to be everywhere for $200 for nearly two years to swap into my '88 GT with zero luck. I suppose in your area they are hanging from trees. If swapping gears in a Ford 8 or 9 inch rear is anyone's idea of hard, they need to buy a new BMW with a rainbow sticker in the window and come out of the closet for good. It is easier and less time-consuming than swapping plugs. Seriously. Also, better get out the tape measure, because that 9 inch you claim is the wrong width is probably narrower than the 8.8 rear, which is why all the cars with 8.8's need to run wheels with a ton of offset just to fit under the older cars. Hey if you or anyone else likes the 8.8, fine, but don't expect everyone to automatically jump on the bandwagon. There aren't a zillion Ford 9 inch rears under everything from Mustangs to Pro-street Chevelles to full on drag cars because they suck.
 

CarMichael Angelo

my rearend will smell so minty fresh,
15 Year Member
Nov 29, 1999
10,641
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Birmingham, al
Nov 26, 2011
#22
  • Nov 26, 2011
  • #22
Nobody said a 9" sucked. (might wanna ck my reply right above yours)
If you think draining and refilling 90 w gear oil, and lifting 100 lbs in and out from under a car on jackstands is convenient and easy, more power to you.
 

Rusty67

20+ Year Stangneter
Dec 3, 2002
3,749
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LA, CA
Nov 26, 2011
#23
  • Nov 26, 2011
  • #23
I've said it once, I'll say it again. The 8.8 rear end is everywhere, widely available and super cheap. You can get an explorer rear end with 3.55 gears and 31 spline axles with the disk brake setup on it for cheap. Oh and don't forget the posi from the factory. You can't get that in a 9" for anywhere near the same price.

Compairing the 8.8 and 9 for a street car is a totally different game then it is when compairing them for a race car. If you are doing a race car don't spend the money twice, just get a 9 and call it a day. For a daily driver (yes C-clips make my skin crawl) the 8.8 is the expedient and cost effective solution to an upgrade over a 8".

If you are having a hard time finding 8.8 rear ends, try anywhere in southern California.
 

Slobin3d

Active Member
Aug 29, 2011
246
17
38
Nov 26, 2011
#24
  • Nov 26, 2011
  • #24
8.8 are all over the place in Montana too although not many of the 31 disk brake units have been showing up, the 31 drum units though are easy to find for under $200 all day long. Here if it isn't a 4x4 truck it doesn't sell, so the junk yards are full of older expoders
 
C

cool40

New Member
Nov 25, 2011
8
0
0
Nov 26, 2011
#25
  • Nov 26, 2011
  • #25
Rusty67 said:
I've said it once, I'll say it again. The 8.8 rear end is everywhere, widely available and super cheap. You can get an explorer rear end with 3.55 gears and 31 spline axles with the disk brake setup on it for cheap. Oh and don't forget the posi from the factory. You can't get that in a 9" for anywhere near the same price.

Compairing the 8.8 and 9 for a street car is a totally different game then it is when compairing them for a race car. If you are doing a race car don't spend the money twice, just get a 9 and call it a day. For a daily driver (yes C-clips make my skin crawl) the 8.8 is the expedient and cost effective solution to an upgrade over a 8".

If you are having a hard time finding 8.8 rear ends, try anywhere in southern California.
Click to expand...
if you have a 8.8 with disc brakes the c-clips should'nt be a problem.for the record i like both 8.8 and 9".for a street car the 8.8 is a good choice,the 9"is in my race car tho......
 

brianj5600

Active Member
Sep 19, 2003
1,964
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39
Middle TN
Nov 27, 2011
#26
  • Nov 27, 2011
  • #26
Mike, I looked for info on how much stronger and F150 housing is over a Mustang and did not come up with anything. I know they have a beefier center and 3.25" tubes which are considerably stronger than the 2.875" Mustang tubes. From what I have been able to find the increase in diameter increases stiffness by 48%. To get the same stiffness from 2.875" tube wall thickness would have to increase from .188" to .320". I am far from an engineer, but I try to do my homework. My math could be completely wrong. If I used a Mustang housing it would have been braced with out a doubt. My turbo will be lucky to go past 800hp. From what I have heard the lack of pro gears is the weak link in a well built 8.8". Do you know how far 3.25" tubes will take me? How about stock caps with a girdle?
 

brianj5600

Active Member
Sep 19, 2003
1,964
2
39
Middle TN
Nov 27, 2011
#27
  • Nov 27, 2011
  • #27
cool40 said:
if you have a 8.8 with disc brakes the c-clips should'nt be a problem.for the record i like both 8.8 and 9".for a street car the 8.8 is a good choice,the 9"is in my race car tho......
Click to expand...

I would not count on disk brakes keeping a broken axle in the housing.
 

CarMichael Angelo

my rearend will smell so minty fresh,
15 Year Member
Nov 29, 1999
10,641
8,909
234
Birmingham, al
Nov 27, 2011
#28
  • Nov 27, 2011
  • #28
brianj5600 said:
Mike, I looked for info on how much stronger and F150 housing is over a Mustang and did not come up with anything. I know they have a beefier center and 3.25" tubes which are considerably stronger than the 2.875" Mustang tubes. From what I have been able to find the increase in diameter increases stiffness by 48%. To get the same stiffness from 2.875" tube wall thickness would have to increase from .188" to .320". I am far from an engineer, but I try to do my homework. My math could be completely wrong. If I used a Mustang housing it would have been braced with out a doubt. My turbo will be lucky to go past 800hp. From what I have heard the lack of pro gears is the weak link in a well built 8.8". Do you know how far 3.25" tubes will take me? How about stock caps with a girdle?
Click to expand...


Brian. You sound way more educated than I am w/ regard to doing your home work. I modified the rear w/ what was available at the time in '07, and I cannot testify as to what is necessary in the stock cap vs billet department. They are cast iron and were never intended to hold a gear carrier in place when 800 ft lbs of torque is thrown at it . (I let that be my modification criteria) You have already obviously modified what you have, may as well use it. At your expected power level, I would expect the tubes to pull. As far as wall thickness, vs strength, you already know the benefits of the truck rear. I used two "kits" to supplement the welded tubes on mine:



This on the rear: ( it looks like the pic depicts it being used on a wusskin 10 bolt chevy rear end, please ignore the 7.5 reference )

View attachment 184100

And this on the front.

If you did this at your anticipated pwr level. I'd be comfortable w/it. Only necessary on a drag strip, though. Again, street tires will always spin before subjecting any "tube bending" axle stress to the rear.

To the OP: This constitutes a thread hijack of sorts, sorry I'm a bad man.
However it does support what is necessary to ultra modify an 8.8 for extreme duty.
 

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brianj5600

Active Member
Sep 19, 2003
1,964
2
39
Middle TN
Nov 27, 2011
#29
  • Nov 27, 2011
  • #29
I doubt I am more educated than you and I know you have more experience. It will be Summer before I get a chance to test mine. I hope it hangs together as is.
 

horseballz

10 Year Member
Sep 30, 2009
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49
Las Vegas, NV
Nov 27, 2011
#30
  • Nov 27, 2011
  • #30
So Just To Re-cap

If I read all this info correctly, for mild to medium duty street use, an 8.8" is:
1- A pretty good/cost effective way to upgrade a one legged 8" with lame gears to trac-loc and better gears and maybe even disc brakes
2- A no-brainer upgrade for a 6-cylinder/V8 conversion from the light duty 4-lug 7 1/4" (or is it 7 1/2")
3- And a "why the heck would you do that" deal if you already have a 9".

Just my conclusion from averaging all the different comments and experiences. Would this be fairly accurate, "in a nutshell"?
Thanx,
Gene
 

dennis112

15 Year Member
May 15, 2005
1,561
36
79
Amish Wonderland of Central PA.
Nov 27, 2011
#31
  • Nov 27, 2011
  • #31
horseballz said:
If I read all this info correctly, for mild to medium duty street use, an 8.8" is:
1- A pretty good/cost effective way to upgrade a one legged 8" with lame gears to trac-loc and better gears and maybe even disc brakes
2- A no-brainer upgrade for a 6-cylinder/V8 conversion from the light duty 4-lug 7 1/4" (or is it 7 1/2")
3- And a "why the heck would you do that" deal if you already have a 9".
Click to expand...

4. An 8.8 offers less rolling resistance compared to a 9."
 

zookeeper

Founding Member
Aug 25, 2001
3,415
63
109
Rogue River, Oregon
Nov 27, 2011
#32
  • Nov 27, 2011
  • #32
Are the thicker F150 axle tubes necessary, or just desirable if you are starting from scratch? Locally there's a late '80's Fox running a BB/trans-braked auto and slicks and it runs 10 flats and still has 4 lug axles. It does have a rear cover like the one pictured that supports the rear caps, as well as aftermarket axles and c-clip eliminators, but it is a standard Fox housing.
 
C

cool40

New Member
Nov 25, 2011
8
0
0
Nov 27, 2011
#33
  • Nov 27, 2011
  • #33
brianj5600 said:
I would not count on disk brakes keeping a broken axle in the housing.
Click to expand...

how would it come out?
 

Rusty67

20+ Year Stangneter
Dec 3, 2002
3,749
37
109
LA, CA
Nov 28, 2011
#34
  • Nov 28, 2011
  • #34
The caliper bracket is cast and not exactly a pillar of strength. If you have a catastrophic failure in the rear end it could easily cause your car to drive in directions other then straight. Trauma could occour which could brake the braket and allow the axle to come out.
 
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