dukester544600

Just wondering how I go about finding out what size my rear end is? I want to change the fluid and I am not sure if I should 1 or 2 bottles of the traction additive. I have a 2006 F-150 FX4 5.4L I am not sure if its the 9.75 or the 10.25, the 10.25 calls for 2 bottles.

Keeblerz28

I would guess the 9.75, but the only way to be sure is to look at the axle code on the door jamb sticker, or crawl under the truck to check the axle tag. Either case, post (or search) for the code you find. That will tell you axle size (probably 9.75), gear ratio (probably 3.73), and that you have L/S.

dukester544600

Axle Code is B6.

boilerup15

check your tag in your jeans, it will tell you what size your rear end is ...sorry i had too.

dukester544600

Very funny, its all good I would have said the same thing!

thump

B6 = 9.75 with 3.73 gearing and limited slip

Keeblerz28

Ding ding ding I win

thump

Yes you do... but in all fairness, are there any 04-08 FX4s that don't use this same axle?

EDDELOS1

mirror ?????? I had to ,,just had to

Keeblerz28

Yea, they probly all have the 9.75, but I heard somewhere that some FX4's came with 3.55's. I know that wasn't what he was asking but checking the axle code applies to everyone's truck axle questions