I have a 1984 f150 and im wanting to put 4.56 gears in to run bigger tires how hard is that to upgrade

 

Depends on axle . Should be a dana 44 front and either a 8.8 rear ( bolt on rear cover) or a 9" (alot easier) but either way if you want to run it on the street alot id get a shop to do it so they get the shims right and the runout right. If you do it you may as well kick in another $300 for a limited slip rear. 90% of these trucks are open diff. If a tire spins all power goes to that tire.

 

What would you recommend it has 3.07 in the front can't read the rear plate not sure on gears but im wanting to run 35's and not tear up the gears

 

You wont "hurt" the stock gears. But it wont pull like you want. 4.56s sounds like a winner. If you can source one get a 5spd from a 87-96 4x4. As long as it was behind a sb it will bolt right up to your 300. Then you can keep or better your economy and still have good power.

 

Thanks man for the feedback