[bigpaulwizzy]

*Foxchassis helped with this thread some info is from him*

If you are wondering what type of rearend or even what size it is this should help. You can find the axle code on the tag that is mounted directly on the axle housing. Another sopt is a white sticker located in the doorjamb there is either a number or letter under axle. Conventional or "open" rear ends break down as follows: 8-2.73, Y-3.08, 5-3.27, F-3.45, 6-3.73. Locking or "Traction Lok" break down as follows M-2.73, Z-3.08, E-3.27, R-3.45, W-3.73.

'79 5.0L Mustangs and Capris did not have Traction-Lok. Traction-Lok was first available in Mustangs and Capris in the '81 model year, and it was optional with the V8, not standard. It became standard with the 5.0L V8 (still optional with the 4.2L v8) starting in the '82 model year.

5.0L mustangs and Capris could not be ordered with a ratio higher than 3.27:1.

There was a 2.26:1 and a 2.47:1 ratio available with a V8 early in the Fox years.

Thunderbird Turbocoupes in '87 and '88 had an 8.8" rear, 3.55:1 with a manual transmission and 3.73:1 with an auto.

Lincoln Mark VII's came with an 8.8" rear, Traction Lok was an option

The only Mercury Cougar that came with an 8.8" rear was the XR7 models and was a Traction Lok with at least a 3.08 gear all others were 7.5"​

 

[EagleAutosports]

Great info. This'll help out a lot of people.

 

[Stang1187]

Yeah i heard the thunderbirds have a direct replacement with disk brakes and 3:55 girls for the fox's

 

[jfb94]

thanks for the info. very informative:bigthumbsup

 

[xxxxxSean Reno]

Do you happen to know if Explorer's have the same axle codes as the Mustangs. Thanks.

 

[FoxChassis]

Do you happen to know if Explorer's have the same axle codes as the Mustangs.

The door codes, no.

The axle tags, yes, somewhat. But those codes were not covered in this topic.

 

[Provy]

thank you for that info...very helpful.. now i gotta wait till morning when it's light out to go see what I got..haha

 

[Provy]

thank you for that info...very helpful.. now i gotta wait till morning when it's light out to go see what I got..haha

 

[93silver fox]

Great Stuff!!:bigthumbsup

 

[red102793]

wow just to see i went and checked out what gears I had in my 88 2.3 it came up as 6 so i guess i have 3.73s:bigthumbsup

 

[Sadler Crew]

I just went out to check my door tag and when previous owner had it painted they tore off the door tag:frustrated:

 

[T-Roy]

Thanks alot man. First thing tommorrow morning, I'm going to check. I'm pretty positive I have 3.73, or atleast thats what I was told when I bought the car.

 

[5.0_H0]

Awesome thanks been wondering what damn gears i had in the back so i could fix my speedo since i put a 140 mph in it !

 

[DnPresident]

I recently bought an automatic 91 5.0 LX convertible and the previous owner told me those came with a weak 2.25 gear for better mpg on highway.

Anyone here know about that? I can say it surely is weak but won't be for much longer with a 4.10 in it I hope

 

[FoxChassis]

No such animal as 2.25:1 ratio. There was a 2.26:1 ratio only in '80 and '81 and only with the 4.2L V8.

The only ratios available for a '91 5.0L/AOD were 2.73:1 and 3.27:1. The former was standard and the later was optional.

 

[DnPresident]

No such animal as 2.25:1 ratio. There was a 2.26:1 ratio only in '80 and '81 and only with the 4.2L V8.

The only ratios available for a '91 5.0L/AOD were 2.73:1 and 3.27:1. The former was standard and the later was optional.

Okay, thanks for the info, maybe the 2.73:1

 

[93 Notchback]

Yeah i heard the thunderbirds have a direct replacement with disk brakes and 3:55 gears for the fox's

Any truth to this, or is this just a rumor? Also, if it's true, what year T-Birds would I be looking at?
I'd like to do this if it's a direct swap. I already have a proportioning valve on the car so that's taken care of.

 

[DnPresident]

No such animal as 2.25:1 ratio. There was a 2.26:1 ratio only in '80 and '81 and only with the 4.2L V8.

The only ratios available for a '91 5.0L/AOD were 2.73:1 and 3.27:1. The former was standard and the later was optional.

All I see is On the rearend cover is There's a metal tag held on by one of the 10 screws with S215A on the top of the tag and L73 88 0L09 on the bottom. Does this tell you anything about the rear end

Also would like to know what size differential cover I have, How do I tell?

 

[FoxChassis]

S215A = axle plant model code (S = Sterling axle plant)
(2)L73 = 2.73:1 gearset w/ Traction-Lok limited slip differential
88 = 8.8" ring gear
0L09 = November 9, 1990 build date

 

[DnPresident]

S215A = axle plant model code (S = Sterling axle plant)
(2)L73 = 2.73:1 gearset w/ Traction-Lok limited slip differential
88 = 8.8" ring gear
0L09 = November 9, 1990 build date

Be nice if every day started out this good:shiny: woW! Thanks for explaining that to me. That really makes me feel better knowing for sure that it is a weak 2:73 which I hope to have changed by the middle of next week. Ring gear size and build date. Great info.

Thank you, thank you:shiny:

Dave