which rear axle

[ncbowhunter]

my truck is a 2004 350 cc dually with 60000 miles and i need a pinion seal already. i know its a dana but which one. is it the 80 and what ring gear is it.

[jphelzer]

I suggest finding the axle code on the drivers door frame and then posting or google'ing the code. That should tell you what you need to know.

[Dave]

I am pretty sure its an 80 but the gearing could be 3.73 or 4.10 I agree you would have to check the axle code or the door sticker

[Raul@Stealth Automotive]

it should be a 4.10 but look at the lil tab on the axle and it will tell you

-Raul

[MrJohnWayne]

It's a Dana 80. Should be 4:10. I think my axle code is C5 but I cant remember and mine is D80 with 4:10 gears.

[MrJohnWayne]

ok I don't know where I got that code from cause I checked mine and it is not listed on the sticker, but you can check this site out and it shows the code/ratio plus where to look on the rearend if it is not listed

Automotive What is my Ford rear end ratio, do I have positraction

[Strõkër~X]

that dually should be a 4"10 rear for sure.

[Dave]

not all the duallies are 4.10s we had two at work that had 3.73 rears an early 99 and an 01

[ncbowhunter]

ok so i found out that i have the dana 80 4.10 with 11.25 inch ring gear. im going to try and install a new pinion seal this week. all the fords ive ever seen have a leak at the pinion seal. anyone tried this and who's seal did you use. i got one from napa for 19 bucks. i hope it lasts longer than the factory one did. oh i found out that i need to get some real tools for this job. the baby tools i have are not going to cut it for this truck. what size is that pinion nut anyway. looks like a 2 inch to me.

[MrJohnWayne]

I think it is 1 15/16. I've done it on my F250 and my old F350 but can't remember. On both I've used the napa seals and no problems after. I still need to replace the one on my 350 now.