Yeah that's what I am worried about cause if I have 4.88 then it probably isn't worth it to go to 5.13 financially for the amount of gain. I would hope the shop wouldn't have seen I already had 4.88 and said 3.73 so I buy gears and I can't imagine they could be that far off when they got up under and spun the tire to check. I guess I'll have to jack it up and check
I have an open dif so I jacked up one side and turned the tire two times the driveshaft turned almost 5 times 4.88.... i
So from my method I have 4.88s which matches exactly with the calculator. Kinda mad the shop didn't get it right saying I had 3.73. I am still considering pressing with 5.13s anyways since I am doing an air locker in the back anyways
My guess is that whoever regeared the Jeep left the factory 3.73 tag on the diff. The shop probably just looked at that instead of checking it like you did.
What is the actual size of the tire stamped on the sidewall?
..and it looks like you have validated the 5.13 advice given here in a blind test.
Exactly. Those numbers are spot on. I don't know how anyone could live with 3.73s with the overdrive auto. I have 4.88s and want more lol.
MarioLJ
New Member
Brandon how are you liking your regearing? Did you end up with 5.13? I’m very excited to hear what you got. Thanks man! I’m running 33’s on a 42RLE too on my 05 LJ
Brandon hasn’t been on the forum since April 2020, but 513 with 33’s would be correct.
I'm running 5.38 with 35s. 5.89 would be nicer. This means that 5.13 still isn't enough to push 33s, except that the Dana 30 can only go to 5.13.
Since we're here on this old thread, I have a couple questions as I plan on eventually going from my present 31" tires, 3.73 and 42RLE to 33" tires and a re gear. I'm in the same boat as far as the OP, wanting a good highway cruise as the closest off roading is 100 miles away. What I do now is shut off the OD up to 65-70mph on two lane state hwy and turn it on above 70 on flat ground. Doing this my MPG stays about the same, 14mpg.
So I guess my first question is what are 5.13s likely to do to my MPG?
Am I correct in assuming that overall this will improve offroad driveability?
Will 5.13 work with my carriers? Dana 30/Dana 35
I'm sure I'll have more questions (wifey interrupted my thought process
) but I guess in general what are the negatives of 33"/42RLE/5.13 on the road whether around town or on the interstate?
So I guess my first question is what are 5.13s likely to do to my MPG?
Am I correct in assuming that overall this will improve offroad driveability?
Will 5.13 work with my carriers? Dana 30/Dana 35
I'm sure I'll have more questions (wifey interrupted my thought process
) but I guess in general what are the negatives of 33"/42RLE/5.13 on the road whether around town or on the interstate?
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Your mpg should not suffer at all with 5.13 and 33's, it would likely be better than with even 4.88. From just my experience, my TJ with 35's, 42RLE, and 4.88 my mpg went from 11 to 14.6 mpg after regearing it to 5.38. If I could have gone even one ratio lower than 5.38 I would have done so just to give me a few more highway cruising rpms. The rpms are still not quite high enough even with 5.38 and 35's to make me 100% happy.
Since we're here on this old thread, I have a couple questions as I plan on eventually going from my present 31" tires, 3.73 and 42RLE to 33" tires and a re gear. I'm in the same boat as far as the OP, wanting a good highway cruise as the closest off roading is 100 miles away. What I do now is shut off the OD up to 65-70mph on two lane state hwy and turn it on above 70 on flat ground. Doing this my MPG stays about the same, 14mpg.
So I guess my first question is what are 5.13s likely to do to my MPG?
Am I correct in assuming that overall this will improve offroad driveability?
Will 5.13 work with my carriers? Dana 30/Dana 35
I'm sure I'll have more questions (wifey interrupted my thought process
All these low gearing recommendations are consistently made primarily for on road driving.
I'm getting around 10.5 to 11 mpg with 33s, 42RLE, and 4.11 factory gears (as far as I know anyways). Does that sound right? I was used to the 14 to 15 in my Sport with 31s, 3.73, and 42RLE.
Yep that sounds about right. Regear to 5.13 and it should improve to over 14 mpg. That mpg improvement should pay for the regearing in 30-40 years, do it!
Dang. I was afraid you would say that lol.