Ford Truck Enthusiasts Forums - Full Floating Axle

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Full Floating Axle

I have a 1978 F-250 Custom,and I need to replace the rear, Full Floating Axle. In order to find another one to fit, I need to find the gear ratio. I looked on the tag on the differential, but I don't know what the numbers mean! Can anyone help me?
This is what the tag says: 3 54(1?) EDD7I(1?)A AEB
603901 2
Some of the numbers I wasn't sure of,as you can see above, because there were some rust spots. I wasn't sure if the first number four was a one, or If the "I" in the third section of numbers was a one.

Hi and welcome to the forum :)

3.54 is the ratio. If the 1 after the 3.54 is a L, then it could be limited slip.

Quote:

Originally posted by LxMan1
Hi and welcome to the forum :)

3.54 is the ratio. If the 1 after the 3.54 is a L, then it could be limited slip.

Agreed, it should have 3.54 gears. But shouldn't the L be between the 3 and the 5 if it has limited slip??

usually, wasn't for sure on the big rearends

On the Dana's its 354L for limited slip.