Gear Ratio?!

[Fordbronco69]

Was wondering if there is a way to tell what ratio i have on my dana 44 and 9" rear axle? ( Thx

 

[Stephen Hawk]

There is supposed to be a small metal tag bolted onto the differential from the factory with the specs stamped on it like gear ratio, trak-lok ect. It should be bolted on with one of the cover bolts on the dana and the third member bolts on the 9". The only otherway is to open them up and count your ring gear teeth and divide by the pinion gear teeth. Unless you're sure its never been changed then look in a haynes or chiltons manual for your year model.

 

[STLKIKN]

If your truck hasn't been modified from stock, on the VIN plate on the glovebox door, there is a space for "axle."

This code will give you the factory installed gear ratios.

If you have a 302 you most likely have 3.50 and 3.54 gearing.

If you have the 170ci 6 cyl, the gears are more than likely 4.10 and 4.11.

Post your axle code, someone will decipher it for you.

Just re-read your post... obviously it has been modified from stock if it has a 44 front.. Your best bet is going to be to pull the front cover. Depending on the gear manufacturer, you will either have to count teeth and divide, or the number of teeth will be stamped on the ring gear.

 

[Txquadhunter]

78-79 Bronco's never had 302's or 351w's 351m/400. Most likely ratio will be 3.50 Front and 3.50 rear. The axle code is found on the tag on the end of the door. So if the door and/or axles never been replaced will be the easist place. going by memory here so don't quote me axle code 14 is 3.50.

 

[STLKIKN]

hehehe...

I read his user name and assumed he had a 69....

ooops. never even looked at the category....

 

[unreng]

Fb69,

put the truck in four wheel drive. mark both driveshafts with a visible mark (that can be seen from the side of the vehicle).

for the rear:

1. chock the front tires

2. lift the rear axle until the tires clear the ground

3. count the number of times the driveshaft turns as the tire is rotated through one complete revolution.

for the front:

1. same as the rear, but reversed.

hope this helps. >-

chris

 

[Ice Man 860]

another way wich also gives u a good chance 2 inspect and replace the oil in your pumpkins is to go out and get some 90 weight and the gaskets for the pumpkins. then drain them and crack em open. then count the teeth on the ring and pinion gears. then u simply divide the number of teeth on the ring gear by the number of teeth on the pinion gear ie. 39 teeth on the ring gear & 11 teeth on the pinion gear = 39/11= 3.54...

if your pumpkins are anything like mine you are probaly need to replace the gasket any ways, so just "**** 2 birds w/ one stone"

 

[Seabronc]

unrenq's method is the easiest way, but if you have a limited slip differential vs a locker, you should rotate both tires at the same time. For that you will need a friend turning one wheel at the same speed you are while you count the shaft revs.

Good luck, >-