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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

what 8.8 will work?

  • Thread starter Thread starter 1fstpony
  • Start date Start date Jun 5, 2007

1fstpony

Member
Apr 12, 2005
76
0
6
Iowa
Jun 5, 2007
#1
  • Jun 5, 2007
  • #1
I have an 86Gt that needs a rear end installed.I want to put an 8.8 in instead of a 7.5. What years will work.Is it just through 93 of will the later years work? Also are they a direct bolt in? Thanks
 

cenok is family

15 Year Member
Jun 25, 2003
1,409
69
79
Norman, Ok
Jun 5, 2007
#2
  • Jun 5, 2007
  • #2
any will work. they are direct bolt on. 94+ are gonna be i think 1/2 to 3/4" wider on each side and are probably gonna be 5 lug. not sure about brake line fitting though. just find a junk stang in a salvage yard and pull the rear for like $40.
 
8

86bluecobra

Advanced Member
Dec 20, 2004
4,265
12
69
B.C. Canada
Jun 5, 2007
#3
  • Jun 5, 2007
  • #3
Your 86 mustang if it was a GT has a 8.8. You can just rebuild it. It is quite simple.
Here is a link: http://www.redpulsar.us/~coldfusion/tlok.html

If i reread your post correctly you don't currentally have a rear end? Then any from a 86-93 will work nicely.
 

86nu

New Member
Jan 6, 2007
94
1
0
Birmingham, Al
Jun 5, 2007
#4
  • Jun 5, 2007
  • #4
also, the cougars and thunderbirds from the mid 80's that still had the solid rear axle will work, so will a mark 7 i believe also.

I know for sure the cougar/thunderbird, b/c thats whats under my car now
 

1fstpony

Member
Apr 12, 2005
76
0
6
Iowa
Jun 5, 2007
#5
  • Jun 5, 2007
  • #5
Thanks guy's
 

93 LX

Founding Member
Jun 2, 2000
3,081
3
0
Norwalk, CA.
Jun 5, 2007
#6
  • Jun 5, 2007
  • #6
86nu said:
also, the cougars and thunderbirds from the mid 80's that still had the solid rear axle will work, so will a mark 7 i believe also.

I know for sure the cougar/thunderbird, b/c thats whats under my car now
Click to expand...

MK 7 has a 7.5. The only T-Bird that has a 8.8 is the Turbo Coupe, 87-88. It is also wider with the disk brakes and the quad shock mounts are different.

I thought 8.8 Rear ends were in 87 through present stangs. I thought 86 Stang had 7.5 rear ends.

Allen
 

86nu

New Member
Jan 6, 2007
94
1
0
Birmingham, Al
Jun 5, 2007
#7
  • Jun 5, 2007
  • #7
93 LX said:
MK 7 has a 7.5. The only T-Bird that has a 8.8 is the Turbo Coupe, 87-88. It is also wider with the disk brakes and the quad shock mounts are different.

I thought 8.8 Rear ends were in 87 through present stangs. I thought 86 Stang had 7.5 rear ends.

Allen
Click to expand...

cougar/thunderbird are the same right? I got an 88 cougar rear end under my car that is the exact same dimensions as my buddies 92 mustangs rear end
 
8

86bluecobra

Advanced Member
Dec 20, 2004
4,265
12
69
B.C. Canada
Jun 5, 2007
#8
  • Jun 5, 2007
  • #8
93 LX said:
I thought 86 Stang had 7.5 rear ends.

Allen
Click to expand...

86 GT was the first year of the 8.8. The 85 H.O. cars still had the 7.5.
 

jrichker

StangNet's favorite TOOL
In Remembrance. Thank you for your contributions
Mar 10, 2000
27,512
2,811
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Dublin GA
Jun 6, 2007
#9
  • Jun 6, 2007
  • #9
Do the 87-88 T-Bird Turbo Coupe rear end swap!

Auto trans 87-88 Tbird Turbo Coupes come with 3.73 gears and manual Turbo Coupes come with 3.55 gears. Cost is $125-$300 for the rear axle. Add another $100-$200 or so to complete the brake upgrade.

I choose 3.55 since I do more highway driving. Both ratios have 10” disk brakes with vented rotors as standard equipment.

It takes 2 guys the first day to get the old rear end out and the new one bolted in place. It takes 1 guy another whole day to do the brakes.

You will need a several sets of fittings, I recommend that you get them from Matt90GT's website, http://www.svo73mm.cjb.net/. Read Matt's instructions thoroughly, everything you need to know about the brakes is all there. You need to be patient and follow all the internal links, and there are many of them. You will need 2 fittings in the rear to adapt your old brake tubing to the TC disk brakes. The fittings go between the steel tube and the caliper brake hose. You will need another set of fittings to make a 2 port to 3 port adapter. To make life simpler, just buy the kits from Matt. You could piece them together, but it's not worth the time unless you work at an auto parts store with all the fittings ever made.

You will need to drill the quad shock mounting holes 2” below the holes drilled for the Turbo Coupe mounting points. The bolts are metric, so don’t loose them or the nuts. A 15/32” drill should be about the right size unless you have access to metric sized drill bits. Going without quad shocks is not an option unless you have aftermarket parts to soak up the wheel hop.

You will need a proportioning valve, Summit has one for $40 + shipping.
You will need a kit (FMS makes the part) to gut the stock proportioning valve, Summit also has that, about $10.


You will need a new master cylinder, see Matt's site and make you choice. I used a 94-95 Mustang master cylinder. Note that rebuilt 94-95 Mustang master cylinders do not come with a reservoir. That means a trip to the junkyard and some more money spent.

Your brake pedal may be very hard and almost impossible to lock up the brakes. I had to replace the front calipers with 73 mm calipers from a 91 Lincoln Mark 7 to get the braking performance up to par.

Bleeding the brakes will require 2 people and some coordinated effort. I don’t recommend using you wife or girlfriend to pump the pedal – they get offended when you yell at them. I used a homemade power brake bleeder constructed from a garden sprayer and some fittings from Home Depot. It cost about $25 and was worth every penny. See http://forums.stangnet.com/showthread.php?p=6143048 for details and pictures.
 

93 LX

Founding Member
Jun 2, 2000
3,081
3
0
Norwalk, CA.
Jun 6, 2007
#10
  • Jun 6, 2007
  • #10
86bluecobra said:
86 GT was the first year of the 8.8. The 85 H.O. cars still had the 7.5.
Click to expand...

I have a 86 Stang 5.0 HO LX vert, I will have to check it out this weekend to see if it does have a 8.8

Allen
 

SVT32VDOHC

waiting for the next hack atta
Founding Member
Nov 22, 2001
3,501
28
119
Motor City
Jun 6, 2007
#11
  • Jun 6, 2007
  • #11
Just stick to an 87-93 8.8 That way it will bolt right in with no messing around.
 
T

tc83bird

New Member
Mar 12, 2009
1
0
0
attleboro ma
Mar 12, 2009
#12
  • Mar 12, 2009
  • #12
8.8 swap

jrichker said:
Do the 87-88 T-Bird Turbo Coupe rear end swap!

Auto trans 87-88 Tbird Turbo Coupes come with 3.73 gears and manual Turbo Coupes come with 3.55 gears. Cost is $125-$300 for the rear axle. Add another $100-$200 or so to complete the brake upgrade.

I choose 3.55 since I do more highway driving. Both ratios have 10” disk brakes with vented rotors as standard equipment.

It takes 2 guys the first day to get the old rear end out and the new one bolted in place. It takes 1 guy another whole day to do the brakes.

You will need a several sets of fittings, I recommend that you get them from Matt90GT's website, 87-93 Mustang 5.0 Brake upgrade pages. Improve your 60-0 times!. Read Matt's instructions thoroughly, everything you need to know about the brakes is all there. You need to be patient and follow all the internal links, and there are many of them. You will need 2 fittings in the rear to adapt your old brake tubing to the TC disk brakes. The fittings go between the steel tube and the caliper brake hose. You will need another set of fittings to make a 2 port to 3 port adapter. To make life simpler, just buy the kits from Matt. You could piece them together, but it's not worth the time unless you work at an auto parts store with all the fittings ever made.

You will need to drill the quad shock mounting holes 2” below the holes drilled for the Turbo Coupe mounting points. The bolts are metric, so don’t loose them or the nuts. A 15/32” drill should be about the right size unless you have access to metric sized drill bits. Going without quad shocks is not an option unless you have aftermarket parts to soak up the wheel hop.

You will need a proportioning valve, Summit has one for $40 + shipping.
You will need a kit (FMS makes the part) to gut the stock proportioning valve, Summit also has that, about $10.


You will need a new master cylinder, see Matt's site and make you choice. I used a 94-95 Mustang master cylinder. Note that rebuilt 94-95 Mustang master cylinders do not come with a reservoir. That means a trip to the junkyard and some more money spent.

Your brake pedal may be very hard and almost impossible to lock up the brakes. I had to replace the front calipers with 73 mm calipers from a 91 Lincoln Mark 7 to get the braking performance up to par.

Bleeding the brakes will require 2 people and some coordinated effort. I don’t recommend using you wife or girlfriend to pump the pedal – they get offended when you yell at them. I used a homemade power brake bleeder constructed from a garden sprayer and some fittings from Home Depot. It cost about $25 and was worth every penny. See how hard is it to bleed brakes? - Mustang Forums at StangNet for details and pictures.
Click to expand...

thanks for the info I swaped out my blown 7.5 for an 8.8 out of a stang but has 3.73 and the car just wont go....i need to put 3.55 in....
 
3

347HO

Member
Jan 13, 2008
462
2
16
Seattle
Mar 12, 2009
#13
  • Mar 12, 2009
  • #13
My 86' LX 5.0 has the 8.8" in it.
 

93 LX

Founding Member
Jun 2, 2000
3,081
3
0
Norwalk, CA.
Mar 12, 2009
#14
  • Mar 12, 2009
  • #14
tc83bird said:
thanks for the info I swaped out my blown 7.5 for an 8.8 out of a stang but has 3.73 and the car just wont go....i need to put 3.55 in....
Click to expand...

Unless someone installed 3.73 and you are sure it does indeed have 3.73s, 3.55s are taller so your car will go less.

What exactly do you mean "Wont go"?
 

Beasty306GT

Active Member
Dec 19, 2002
671
4
28
Oxford,Mass
Mar 12, 2009
#15
  • Mar 12, 2009
  • #15
Wont go????? DO you have the correct gears that u think u do...3.73 should put u in your seat
 
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