I'm shopping for my Dana 80 and I keep seeing some of them listed as 3.55 but my truck is 3.54. Is this actually a diffrent rear gear or are people just listing them wrong or am I missing something?

 

if they are both dana then they are the same ratio some old Fords use a 4.11 in the rear with a 4.09 in the front. they say it peforms better.even if they were off by .01 you won't even feel it. well thats what i have heard.

 

I kinda figured as much but always like more input.

 

i think you will find most of those numbers are rounded. for example if you have 39 on the ring and 11 on the pinion you get 3.54545454 ect. the decimal doesnt end. some people round it down to 3.54 some round up to 3.55 i hate to ramble but i have no clue where 4.09 and 4.11 come from cause usu it is 41 on the ring and 10 pinion. that comes to exactly 4.10 but i guess i shouldnt rant

 

See I learned something new. More input is a good thing.

 

5 psi of air pressure difference would make more of a difference then that. And I agree, its common. I had a chevy with 4.11's and 4.09's.

 

no flame intended, 45~11= 4.0909 / 37~9= 4.1111 / 29~7= 4.1428

 

none taken crewcab, in fact i apriciate the chime in i just have never seen those combos. i work mostly on dana 70 and 80 rears