Tire size change

I run closed shoulder drives. 1500 rpm 72mph 18718B 3.70. I don't have a 6nz so idk about fuel mileage.. And don't really keep track of mine..

 

If you can get a set of the lower rolling res.11-24.5 tires it will not hurt as bad, you can look on AMBT amer. moves by truck.com web site to ck most tires roll/res. are listed over on that site.

 

It'd be pretty similar to keeping the LP22.5's and swapping the rear gears for 3.36ish. Your best bet, since you've already got the 22.5" rims and need tires anyway would be to just go to an 11R22.5...same diameter as a LP24.5...and see how you like it (equivalent of 3.55ish rears with your LP22.5's). If that change isn't sufficient but gets you a little closer to what you want, THEN spend the $$$ and get the 24.5" rims and 11R24.5 tires. If you decide at that point that you liked the 11R22.5's better, you can drop back to LP24.5's and have the same thing without having to put 22.5 rims back on your truck.

 

Depends how fast you want to go. Lp22.5 to 11R22.5 3-4 mph. Lp22.5 to 11R24.5 6-8mph.
Google road speed calculator and play with the numbers.

 

You would see about a 250 rpm drop.

That would be the equivalent to about 2 steps higher axle ratio.
Any negative effects from higher rolling resistance will be out wieghed by better mpg from the lower rpm while cruise.

Truck will ride a lot nicer with the tall 24.5 also.

 

Ive got 2 stars that are identical.
1 truck has low pro 24.5 with 3.55
2 truck has tall 24.5 with 3.70.
Same od in trans.
Both run same cruise rpm.
The truck on tall 24.5 rides a bit better.

You will have to get your speedometer adjusted for the taller tires after. Thats not hard thou. Should just be a ecm perimeter change.

 

This ^^^ try 11R22.5 tires before spending a bunch of money switching to 24.5 wheels. I have a C15 with a 13 speed, 3:70 rears and 11R22.5 and I think it's geared just right - a good combination.