I have a 2006 Screw with 35" tires and a 6" lift. I'm still running my stock 3.55gears. I do a lot of freeway driving to work but I also tow a 22 ft travel trailer (about 6200 pounds loaded) about 10 times a year. I live in Arizona and do some pretty steep climbing in some areas. My truck seems to do fine on the flats but boggs down quite a bit pulling the hills. i didnt know whether to do the 4.56 gears for pulling or do the 4.11's and add an intake and programmer for my highway driving. Anybody with an 04-07 5.4 with a lift and gears had any problems with either size gears. I'm hesitant about doing 4.56 gears as I dont want my truck to be screaming cruising down the road to work. Thanks guys

 

For 35" tires you should go with 4.56's. I think you should get the intake and the programmer anyways not just if you went with the 4.10's. I have 4.56's and its great.

 

4.56

 

4.56

 

I also have 35' tires and a lift with the stock 3:55's. I was wanting to bump up to the 4:10's....Will the 4:56's be that much better than the 4:10's?

I'm not expecting an increase in mileage but, I am hoping not to lose a whole lot either.

..apologies for the hi-jack bigliftbb.

 

Yes 4;56 will be that much better.

 

There's also 4.30s if you want to hedge your bet.

 

not if you have the 9.75 there arent

 

4.10s would be waste of money with those tires.
You need 4.56 at the least.

Lots of us run (or ran, because I sold mine) run 4.10s on street-size tires.

 

Do the 4.56's fit without any major modifications?

 

The shop can just install them no problem. If you don't already have a LSD installed then now would be the time to do it as well, since the shop is already in there...you'll save a bit on labor and fluid