ZachStack

So what kind of gears are you running with 33" tires? the rear end in my truck is not stock and i do not know if its been regeared. its out of an f150 with a 5.4l mine has a 4.6l it orginally had the 8.8 with 3.55 gears...now its got a 9.75 with idk wht gears. i dont know what it usually comes with in a 5.4l

also...who is running long tube headers? OBX makes some and i would like to know if anyone has got them and how hard they were to do. Thanks guys.

would love some advise guys! Thanks!

ZachStack

Also...what size tires are 315/70/16?
i know 305/70/15 is about a 33"

im thinking about getting the 315.70.16 for my next tires.

Pity7700

you shouldnt need to regear, youll be fine with 33s. the 5.4s also came with 3.55 but im not sure if they were in the 9.75

a 305/70/15 is a 31.8" tire a 315/70/16 is a 33.36" 315/75/16 is a 34.6" tire

ZachStack

Thanks. i was just curious cuz i dont want to ruin a brand new transefercase. it was brand new in the truck when i got it. which worried me a little bit...but it had the stock rear end in it when i got it. i put the other rear end in it. but i didnt know what gears were already in it

01SilverCrew

All 5.4s are not the same and have different rear ends. There should be a plate on the rear end with numbers if Im not mistaken and you can look up what it is. My 5.4 has the 3.55 LS (limited slip)

ZachStack

the only reason i swapped it over is because it was awesome off road...and i like it a bit more than the 8.8

ZachStack

But thank you for the info. i will have to look at that here in a bit.

ZachStack

But i did notice that my gas milage got worse after i swapped the rear ends...i was getting 20 mpg witht the 8.8 and now im gettin glike 17mpg witht the 9.75

skizriz

Better find out what gears it has before you use 4wd. Mismatched gears between the front and rear is a sure way to ruin the transfer case.

lifted97