Try Grimmjeeper.com, then think about where the rpms should be at your normal top speed.
X5 or whatever on the 4.56 axle ratio (you must regear both axles) recommendation for 35" tires with your 32RH 3-speed automatic transmission. And as said above, don't do math to figure out what gears will cause the engine to run at the same rpms it did with the smaller factory size tires. Larger tires are harder to turn and have more leverage against the drivetrain which means you need higher rpms than stock to turn larger diameter tires and have the same power on the road. 4.56 will accomplish that with aplomb.
X5 or whatever on the 4.56 axle ratio (you must regear both axles) recommendation for 35" tires with your 32RH 3-speed automatic transmission. And as said above, don't do math to figure out what gears will cause the engine to run at the same rpms it did with the smaller factory size tires. Larger tires are harder to turn and have more leverage against the drivetrain which means you need higher rpms than stock to turn larger diameter tires and have the same power on the road. 4.56 will accomplish that with aplomb.
A question along the same line. A 2006 LJ 4.0 and a 6 speed, currently running 3.73’s, does feel a bit boggy on steep uphills. Would 4.56’s be recommended with this setup as well? How would the lower gears affect the highway use?
I would lean towards 4.56 based on putting 75mph near 3k rpm. You can confirm the math on Grimmjeeper.
I can say on the 5 speed AX15 it puts 75MPH(GPS) at 2750.(give or take 100) with 4.56 and 33" copper stt pros. each tire will be a diferent size. I have not found a 33" tire that was 33" exact. they very by +/- 3/4"
Of course they vary from the exact measured size, I've never seen a tire for a Jeep that measured exactly what the sidewall says. Like when your child says how long until we get there daddy and you say an hour rather than saying 56 minutes and 34 seconds per the GPS. It's close enough for any but the most anal of us.
i find it quite comfortable at 75-80. i really don't need to be going that fast but i can if i need to pass someone. On Friday i get me new speedo gear and will install it monday morning. that way i can get a better indication of what it does. i don't like having to keep checking my phone to tell true speed.
Being over 40 without kids. I never thought about the impact of GPS arrival times when you have kids.Of course they vary from the exact measured size, I've never seen a tire for a Jeep that measured exactly what the sidewall says. Like when your child says how long until we get there daddy and you say an hour rather than saying 56 minutes and 34 seconds per the GPS. It's close enough for any but the most anal of us.
You have a different overdrive gear than the nsg370. My nv3550 has nearly the same OD as your ax15. My 4.88s with 33s put the Jeep's 75mph at 3000 rpm. My speedo is very close to GPS.
As a Courier, I drove an S-13, V6 Dakota and V8 Tundra around a million miles.
