Brent,
Your '76 should be a 3.9. If you want to be sure, clean of the area on the
upper right (passenger side) of the diff casting and look for two numbers
near the flange, usually on a boss at the top of the case. a 3.9 will have
the numbers 10/39 stamped in the aluminum.
Gerard
At 9:59 PM -0500 11/20/01, Brent Wolf wrote:
>While I was under the 76 playing with the brake hose, I got to thinking (I
>know - shouldn't do that) about the final drive. Why are my rpm's so high
>at 50 mph (about 3400). If my final drive is 17.3 mph per 1000, then I
>should be flying down the road at almost 60 (58.8). Anyway. I was also
>told it sounds like a 4.22 diff is installed (about 15 per 1000) So I looked
>up an old driveline info section and was read - To determine final drive
>ratio, raise one wheel, mark driveshaft, mark wheel, rotate wheel one (1)
>revolution and count driveshaft revs. (3.9 = 3.9, 3.7 = 3.7, 4.2 = 4.22).
>Ok easy enough.
>
>There must be something wrong or I can't follow instrucitons. My drive shaft
>rotated exactly 1.95 revs (not quite 2 and more than 1.9) per wheel
>rotation. What am I doing wrong? Is there anyway short of pulling apart
>the diff to determine what is inside?
--
Please visit Four Points Travel -
Discount Online International Travel Reservations
http://www.gerardsgarage.com/fourpoints
To make a reservation please call Toll Free 1-800-272-3253
G G Gerard Chateauvieux
E A
R R pixelsmith@gerardsgarage.com
A A
R G Pixelsmith on Duty
D E
S http://www.gerardsgarage.com
|