LeSabre Rear End

[SABRCAT]

I have a 1978 Buick LeSabre Sport Coupe. Anyone know what the rear end gearing is?

 

[BiGBoY]

I don't know what you have in the back of your '78 Sport LeSabre but here the infos I found in my Chilton' Labor Guide and Parts Manual 1978:

In 77-78 you could find in a LeSabre:
2.41:1 with:
7.5'' ring gear
8.5'' ring gear
8.75'' ring gear
2.56:1 (I don't know,not specified)
2.73:1 with:
8.5'' ring gear
8.75'' ring gear
3.08:1 with:
8.5'' ring gear
8.75'' ring gear
3.23:1 (I don't know,not specified)

I don't know and I didn't find which one come with the limited slip package or not...I believe it's not the Buick bible I got in my hand altough I found great infos ! In another book (a better one) I found the turbo package came with a specialy calibrated automatic trans and special rear axle ratio.... what could be the special here ?

As I'm reading at the same time I found another numbers for you !!!!!!
leSabre V6: 2.73:1
LeSabre V8: 2.41:1
LeSabre Sport Coupe V6: 2.58:1 (maybe a wrong data....I never see a 2.58...it could be 2.56 but it have to be checked)
LeSabre Sport Coupe V8: 3.08:1
The other rear axle ratios could be found in hight altitute area or in california cars. (these numbers have been taken from Standard Catalogue of Buick 1903-1990)



If you really want to know what could be your final ratio, jack up your car on 2 candles. Trace a little straight line on your differential (a mark) and rotate a wheel by one full turn (not on park of course ) and see how many rotations your differential have made. It's the easiest way to calculate it without taking appart your 3rd member The other way is to find your factory build sheet (often under the backseat and on top of fuel tank)

Gimme news if you find the real data !!

 

[Silver 6]

My 79 L/S Sport Coupe has a tag saying 2.73 on one of the bolts for the rear cover. It is a 8.5 open rear with 5X5 bolt lug pattern.

The Buick Product Selling Information guide for 79 shows Model F37, Engine STD LC8, Axle STD 3.08 for both federal and California. I would think 1978 was about the same.

Then a check of the Buick Color, Trim & Selling Manual shows a 2.73 for federal and 3.08 for California. This would be correct for my car. It also shows an option of 3.23.

Ring gear, O.D.......7.5(301 CID), 8.5 (All Others)

 

[turbofish38]

SABRCAT and David, If you want to go through some extra effort, clean off the right (passenger) side tube on the axle housing. There is a code stamped into the tube. I can tell you what ratio and ring gear size the rear is if you PM me the code. Thanks Eric Fisher. P.S. David how long have you owned your 550 Katana? I have a 82 GS1000SZ Katana I bought with 250 miles on the odometer in 1983. It's interesting how great minds think alike.

 

[SABRCAT]

Found it!

It says 3.08. Thanks guys!

 

[Silver 6]

I'd have to look at my dealer paperwork to be sure of the exact date in May(I think) of 82. It spent more time in shipping some times than under my butt. I bought it in Utah when I was stationed out there in the Army, then to Germany, then Wisconsin, then Virgina, and now Minnesota. Time to do the carbs, again, and this time the calipers too.

 

[Peter]

The 1978 Buick chassis manual says 2.73 for the coupe, but I have never checked mine.