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Christ · 02-03-2010, 03:28 PM

Regarding the axle ratio -

It turns out that my Father actually has an 80-something F150 with an axle tag that says 18. Yep, 3.08 ratios.

Caveat - They broke the rear end about 13 years ago, and he doesn't know if they actually replaced it with a 3.08 or not. I can at least get the front diff, though, since I know that's still OE.

Guess I'll have to count teeth on that rearend and hope for the best?

I've looked around and found that I should be counting 40/13 to get a 3.08 ratio.

Turns out I have a Dana44 front axle, as well. Gonna see if I can find anything lower than 3.08 for the D44.

Darn. I'm not seeing anything lower than a 3.08 without going to a completely different front axle, and as much as I'd prefer a solid axle, I'm not doing that much fab work. 3.08 it is!

Looks like I won't be able to use big-truck tires, either. The 9.00-20's are 40" tires, and that's wayyyy too big!!!

I guess I'll stick with 15's, and just get some stock steel 7.5" rims and use the stock 235/75 tire.

02-03-2010, 03:28 PM	#26 (permalink)
Christ Moderate your Moderation. Join Date: Nov 2008 Location: Troy, Pa. Posts: 8,919 Pasta - '96 Volkswagen Passat TDi 90 day: 45.22 mpg (US) Thanks: 1,369 Thanked 430 Times in 353 Posts	Regarding the axle ratio - It turns out that my Father actually has an 80-something F150 with an axle tag that says 18. Yep, 3.08 ratios. Caveat - They broke the rear end about 13 years ago, and he doesn't know if they actually replaced it with a 3.08 or not. I can at least get the front diff, though, since I know that's still OE. Guess I'll have to count teeth on that rearend and hope for the best? I've looked around and found that I should be counting 40/13 to get a 3.08 ratio. Turns out I have a Dana44 front axle, as well. Gonna see if I can find anything lower than 3.08 for the D44. Darn. I'm not seeing anything lower than a 3.08 without going to a completely different front axle, and as much as I'd prefer a solid axle, I'm not doing that much fab work. 3.08 it is! Looks like I won't be able to use big-truck tires, either. The 9.00-20's are 40" tires, and that's wayyyy too big!!! I guess I'll stick with 15's, and just get some stock steel 7.5" rims and use the stock 235/75 tire. __________________ "¿ʞɐǝɹɟ ɐ ǝɹ,noʎ uǝɥʍ 'ʇı ʇ,usı 'ʎlǝuol s,ʇı" Last edited by Christ; 02-03-2010 at 05:43 PM..