Skip to main content
Topic: What rear gear is this (Read 1262 times) previous topic - next topic

What rear gear is this

Apparently  I'm missing something or I don't have any data in my DIY link to capture deciphering rear gear Ford axle tags


What rear gear is this

Reply #2
looked at coolcats.net and eric shows some info but im wondering if i see this correctly as a 2.73?

What rear gear is this

Reply #3
Yep......2.73 Limited Slip in a 7.5" rear.

Did they use 7.5's in '88's??  My Sport had a 8.8".
1988 T-Bird Sport Coupe--5.0 HO, MAF swap, 1-5/8" shorties, BBK/Flowmaster exhaust, Explorer intake, 70mm Edelbrock TB, T5, B&M short throw, Centerforce clutch and PP, disc brake TC rear w/ 3.55's, TC front brakes, '98 Cobra springs, DIY SFC's, other misc .  14.05 @ 98mph with launching too low and shifting too high.

What rear gear is this

Reply #4
His 88 sport has this tag.

now, the car really realy pulls hard,, and i cant for the life of me understand why his pulls so well.  My 20th is low geared and his car feels like twice the car.

its got me wondering if the rear has been upgraded.  Car came from an old board member Scott Branner.

What rear gear is this

Reply #5
Quote from: Dan B.;414782
Yep......2.73 Limited Slip in a 7.5" rear.

Did they use 7.5's in '88's??  My Sport had a 8.8".

It was a mixed bag of 7.5" & 8.8" for '88, my '87 Sport had same as Scott pictured...

Possibly had to do with which brakes were on it???

What rear gear is this

Reply #6
Maybe the gears had been changed. I can't see 2.73's pulling hard.


86' T/C 4.6L DOHC
16' Chebby Cruze 1.4L Turbo
17’ Peterbilt 389 600hp 1850ftlb Trq 18spd

[SIGPIC][/SIGPIC]

“Heavy Metal Mistress”
[/COLOR][/SIZE]

What rear gear is this

Reply #7
with identical engines and transmissions, suspension ect.

you would think i would certainly feel the differences, his has dual exhaust 2 1/2'', Exploder upper / lower and a larger throttle body..
if thats all it takes to make life better for the poor ol 5.0, i belive it may not be too much of a sacrafice to deviate from the original aspects of the 20th design to gain in flow.

i like doing the sorta invisible upgrades, i hope i can keep the 20th as close to oem as possible with respect to original design.  i think in a few years id be forgiven for getting rid of a y pipe in trade for dual exhaust and bolt on the BBK's i got long ago from my pal down in va beach!
ooppsssss... back on topic,,,,
yes most certainly the sport compared to the coug with identical rear gears, the sport flat out feels much different.  Im going to call up scott (the last owner) and find out if he did any drive train changes.

What rear gear is this

Reply #8
Jack the rear end of his car up off the ground, Rotate one of the tires a complete revolution, have someone count how many revolutions the driveshaft makes during the one tire revolution.  That will get you in the ballpark for the rear gear ratio that is in the car, in case it had ever been changed.
Mike

 

What rear gear is this

Reply #9
If youre changing the diff fluid, do the tooth counting procedure, # ring gear teeth/ #pinion teeth 41 ring gear teeth/ 10 pinion teeth= 4.10 ratio for example

What rear gear is this

Reply #10
My Sport had a 7.5 stock, 10" drums. (The smooth ones, no fins. This is for future info-seekers.)

Heya, Dan B., was it possible a previous owner swapped in your 8.8, or do you seem to know it was factory? We all know some '88 XR7's had the 8.8 drum rear, this is the first I've heard of an '8 Sport with it. In fact, every Tbird/Cougar I see in the salvage yards, regardless of engine, trim, or options, I always check the rear end, to see what brakes and rear it has.
'98 Explorer 5.0
'20 Malibu (I know, Chevy, but, 35MPG. Let's go brandon, eh)