thinking of getting some 37" tires but i dont want to mess up my tranny or anything along thoses lines im in the process of replaceing all the u joints and ball joints, i have a 98 1500 3in body lift and the previous own put some sort of 3" lift i have 285x75x16's on their now and they look to small.

 

Change gears FIRST.

 

Isn't 285/75 the same as 33" tires? With a 6" lift I'd run agressive tread 35s, not 37s...they'll likely rub. Change gears first.

 

Any recommendations on gears that's something I've never gotten into. But those. Mt's are such a great deal but what 35's would you recommend toyo open country? And just a FYI the picture below didn't have the 3" body lift

 

+1 on 35's unless you are ok with cutting for clearance. Your stock ratio is likely 3.55. Not necessary to change gears immediately but it is a good idea to have future plans to do so. When you do, you will want to be in the 4.56 - 4.88 range.

 

Your truck will be a pig with 35's and 3.55's. Gear it first.

 

I agree, gears first. 4.56 for 35's. If you tow/haul on a regular basis, and don't do a lot of freeway, consider 4.88s.

 

Do we have a tutorial or any thing on here for the gear swap never done that before

 

Lots of money for gears. Go here for the gears and installation kit http://www.ringpinion.com/ Then call around locally for a price to install. You'll need to buy special tools also if you want to attempt it yourself. But I agree with the others, gears first.

 

If you've never done gears before than I don't recommend doing it yourself unless you have a friend or someone who has done them multiple times. Find a reputable shop that has done gear swaps before and knows how to properly brake them in, etc.