I was wondering what axle and ratio would be in a 73 ranchero. 351 C6.
I think it is a 9".

Nathan

 

it's a 9"

there should be a metal tag on one of the nuts that hold the front section in. that will have the ratio on it, and (i think) an "L" if it has trac-loc.

if there's no tag or you think it may have been changed, you can jack it up and turn one wheel with the tranny in park (or in gear if it's a manual). if the other wheel turns the same way, it's trac-loc. if it turns the other way, it's limited slip. it it doesn't turn, it's an open diff.

then put it in neutral and mark a spot on the tire and on the driveshaft. turn the driveshaft, counting the turns until the tire makes one full turn.

 

>
>if there's no tag or you think it may have been changed, you
>can jack it up and turn one wheel with the tranny in park
>(or in gear if it's a manual). if the other wheel turns the
>same way, it's trac-loc. if it turns the other way, it's
>limited slip. it it doesn't turn, it's an open diff.
>

Good advice - but in park nothing will turn. Put it in neutral...

 

>>
>>if there's no tag or you think it may have been changed, you
>>can jack it up and turn one wheel with the tranny in park
>>(or in gear if it's a manual). if the other wheel turns the
>>same way, it's trac-loc. if it turns the other way, it's
>>limited slip. it it doesn't turn, it's an open diff.
>>
>
>Good advice - but in park nothing will turn. Put it in
>neutral...

I was wrong! They will turn with it in park, at least with limited slip posi (found out that's what I have)

 

I decoded the vin and it's a 3:00.1

Nathan

 

that's NOT a good ratio for acceleration!

should be easy on the motor on long highway trips, and good gas mileage on the highway. for city driving, my gas mileage improved when i switched from 3.08 to 3.73 in my mustang. i think it's because the gears make it easier to accelerate, so i'm not having to give it so much gas all the time.

for reference, my '75 ranchero has 3.89 gears and the revs weren't TOO high on the highway - definately fine for everyday driving. 4.11's would get it moving faster, but on the highway i'd probably want to keep the speed down a little - then again, i probably should slow down a bit anyway...

 

 

>if there's no tag or you think it may have been changed, you
>can jack it up and turn one wheel with the tranny in park
>(or in gear if it's a manual). if the other wheel turns the
>same way, it's trac-loc. if it turns the other way, it's
>limited slip. it it doesn't turn, it's an open diff.
>
>then put it in neutral and mark a spot on the tire and on
>the driveshaft. turn the driveshaft, counting the turns
>until the tire makes one full turn.


i think you have that confused. if you leave it in park(or gear) and try and turn a limited slip or trac-loc, then you won't be able to..
if it just turns the other tire in the opposite direction, the it's open.