Can anyone help me out in finding out what the gear ratio is on my F250 2wd auto w/300I-6. The tranny code on the door jam is "K" and the axle code is "29". I would like to either replace the gears or rear end in order to up my mileage a little, I use the truck mainly to commute to work, 35 miles one way. I am getting 13mpg and that's not quite cutting it. I was told there is a 3 speed tranny in it. Please help!!!

 

code 29 is a 3.55 gears

 

I'd consider swapping you my 2.73 rear gears out of my '82 F150.

'82 F150 2WD w/351W (orig 300 I6)
Slik

 

The K code if it is the same as 82 is the c6 tranny.

Steve

 

Thanks for all the help guys.
Slik, Where do you live and how hard would it be to pull the gears myself with a standard set of tools?

 

I live in Durham, NC; it would probably be easier to swap the entire rear end drum to drum. From what I hear, it's a pain to swap the gears and get them setup. How about it folks, maybe some comments from those that really know?? I know I can pull my rear hub to hub with common tools, but I don't know about the gears, etc. Oh, I assume you have the 9" rear?

Slik

 

I couldn't tell you if I have a 9" rear end or not, still a little green to working on Fords and trucks for that matter. Been a parts replacer for a long time.

 

If it's an F250, it's not a 9".