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1995 gear ratio

17K views 26 replies 4 participants last post by  351w  
G
#1 ·
A buddy just bought a 95 F-150 4x4, and wants to know what gears are in it. These are the numbers on the rear end tag: S8325 3188 5F22. The tag in the door says axle code 17. Any one know? The local dealer told home to take it apart and count the teeth, but he don't need to know, just curious. Thanks.
 
#3 ·
Your owners manual will have the info under towing but according to my book, code 17 is a 3.31 open diff. :)
 
#4 ·
Per Ford factory manual for 1995, axle code 17 is a 3.31 non-limited slip drive axle with a 3800 lb Gross Axle Weight Rating.

Dave / Believer45
 
#5 ·
"92 BigBronco, you have faster fingers than me. Beat me by under a minute.

Story of my life! (hee hee)

Dave / Believer45
 
#12 ·
351w said:
i beat ya both with one hand tied behind my back.
he he
I read the post you linked to. Interesting way of doing it with the string. Easy way of doing it if you don't have a floor jack.

One thing though, hate to be a stickler.....so don't take it personal. :)

What if the ring has 32 teeth and the pinion has 15 teeth? By your method, the rear end ratio is 480.....but it's actually a 2.13:1. You divide, not multiply.
 
#13 ·
92bigbronco, i dont know what to say about that you might have a point but i will look into this a little bit more in my spare time.
but i dont think you should divide the numbers to find their ratio.
counting teeth is the most exact method possible but if i divide 31 ring teeth x10 pinion teeth i come up with 3.1 so it still tells me 310 rario.
so my question for you is this.
is it even possible to have 15 pinion teeth and still have 32 teeth on the ring gear.
and if it is how do you come to your conclusion of 2.13 and not 480.
im not asking to be smart i dont understand
 
#14 ·
The numbers I used were only an example but the method is correct. The example you're using works out because you are multiplying by ten. The fact that it ends up being 310 is purely coincidental. You have to divide the number of teeth on the ring gear by the number of teeth on the pinion to calculate the gear ratio.

Think about it.......if the ring gear has 36 teeth and the pinion has 12 teeth, the pinion has to turn 3 times before the ring gear will make a full rotation......thus the 3.00:1 ratio. By your method of multiplying, the ratio would be 432 which isn't even a ratio at all.

If you divide the number of teeth on the ring by the number of teeth on the pinion, 36/12, it yields the gear ratio of 3.00:1.....meaning the driveshaft will spin 3 times for every complete tire rotation. Division is the only way to figure it.
 
#16 ·
Yes, that works fine for calculating final drive ratio.....which is when you multiply to calculate the total gear reduction through the tranny, rear end, etc. and loss of reduction by running larger tires.

I'll tell you what, don't take my word for it, check this site and numerour others on how to calculate the rear end ratio by counting the teeth on the ring and pinion and DIVIDING. It's basic math.....

http://www.csgnetwork.com/rnggrpinioncalc.html
 
#19 ·
89F150 said:
I have the 4.10. I climbed under and sure enough it said 4L10. What code would that be if it was on the door tag? Just for general knowledge.
The axle code is either 2 or 3 digits (two wheel drive is 2, 4x4 is 3 digits to cover the front axle as well)

For your truck, 4.10 limited slip,

B5 5300 lb rated 4.10 limited slip
C5 6250 lb rated 4.10 limited slip
D5 7400 lb rated 4.10 limited slip
F5 8250 lb rated 4.10 limited slip

If there is a third digit (2) then the front diff is limited slip as well.

Dave / Believer45
 
#23 ·
well 89 thats not a thought that had crossed me mind until now so thanks.
actually i was thinkin my truck would probably run pretty good with a set of 410's and that limited slip sounds great as well.
i have one of those lockers installed in my rear and it makes all kinds of noises.