lifted x, bearings, gear, engine questions

[Hermz]

Hi, I lifted my 94 explorer (5.5" lift, 33x12.5 tires) and left my gears alone. My gas mileage is pretty bad now around 11 hw/city. I heard the bearings should go out about every six months. My engine has 150,000miles and is starting to wear out. So I was wondering... how much would do new front bearings cost? Is there any bearing I can buy that wont wear as quickly? Which gears should i put in? How much would the gears be with installation? Also, im switching my engine soon, and was wondering if there's any other more efficent engines that I could replace my engine with, whether it be more efficent in horsepower or gas or both, preferably gas mileage. Thanks

 

[F14CRAZY]

Hi, I lifted my 94 explorer (5.5" lift, 33x12.5 tires) and left my gears alone. My gas mileage is pretty bad now around 11 hw/city. I heard the bearings should go out about every six months. My engine has 150,000miles and is starting to wear out. So I was wondering... how much would do new front bearings cost? Is there any bearing I can buy that wont wear as quickly? Which gears should i put in? How much would the gears be with installation? Also, im switching my engine soon, and was wondering if there's any other more efficent engines that I could replace my engine with, whether it be more efficent in horsepower or gas or both, preferably gas mileage. Thanks

What do you mean go out every six months? Maybe clean and repack them with grease every 6 months, but I couldn't see wheel bearings failing every 6 months if that's what you mean, unless they're put in wrong or you drop them in the dirt before putting them in, or run through water often. I think once a year would be a good interval to pack them at, at least with my usage and synthetic grease.

Buy only Timken tapered roller bearings, preferably from an industrial bearing supply store (cost)

Wait, did you mean wheel bearings or internal differential/axle bearings? My bad.

 

[Hermz]

I believe their front wheel bearings. I think they were replaced with Mog bearings last time or something like that.