If you do end up doing it, definitely post some photos and maybe a how-to write-up. Many of us would appreciate it I'm sure!
If you do end up doing it, definitely post some photos and maybe a how-to write-up. Many of us would appreciate it I'm sure!
Yeah, I’ve been kicking that around and did some research and have decided to stick with 31” tires. BTW I have 3.73 gears right now.
Doing the research at http://www.grimmjeeper.com/gears.html, 4.88 would get your engine spinning at a very efficient 2550 rpms at 70 mph. Yes I know 4.88 seems like a crazy ratio for 31" tires and it would be if you had a 5-speed manual transmission or the 32RH automatic. But for your 42RLE, it'd be a good choice. When I regeared my TJ with the same 42RLE from 4.88 to 5.38 for my 35" tires, everything got better... even the mpg went from <12 mpg to >14 mpg. 4.56 would produce 2380 rpms at 70 mph which is going right on the edge of lugging.
Just know that the 42RLE needs a significantly lower axle ratio than is commonly thought of as appropriate. So please don't be surprised with some of the clueless masses who wouldn't know a 42RLE from a Boeing 737 going berserk hearing 4.88 and 31" tire size used in the same sentence.
And for those who don't know what a lower vs. higher ratio means in ratio-speak, 4.88 is a lower ratio than 3.73 is. 3.73 is a higher ratio than 5.13 is. Put another way, a lower axle ratio gives higher engine rpms and a higher ratio axle ratio gives lower engine rpms.
After 15 years of listening the the 0.69 OD problems, I'd just replace it with the 32RE indestructible 3speed auto. Probably cheaper than a regear too.
No matter what you do with the 4speed auto, you end up with a compromise.
No matter what you do with the 4speed auto, you end up with a compromise.
The 32RH is a no-go for newer TJs, the computers used starting in 2003 don't have the ability to control the 32RH's lock-up torque converter.
Good to know, I'm a clutch fanatic but I'd be tempted to buy a Jeep with the 32RH.
Good, give up. DON'T 'ask again'. I Already said VERY CLEARLY that I had given the thread the wrong heading and CHANGED that to what I meant. The ROOT of my question was " I'm wondering if anyone has experience with upping the differential gears to a point that the 42RLE actually behaves like a normal transmission?" Sorry that confused you so much, but thanks for being so warm and welcoming.
Apparently the OP got so pissed off he messaged me privately asking for his account to be deleted.
All it took was @Jerry Bransford asking him repeatedly for his tire size.
Wow... some people have really thin skin.
All it took was @Jerry Bransford asking him repeatedly for his tire size.
Wow... some people have really thin skin.
I'm sorry you didn't understand the importance of tire size to helping you with what axle ratio would be the most helpful for you. An axle ratio that was appropriate for 33" tires would not be appropriate for 30" or 35" tires. Kind of like wanting the shoe salesman to recommend shoes for you but refusing to tell him your foot size. I still can't figure out why you were so adamant about not providing such a simple thing as your Jeep's tire size. Oh well, your loss.
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Getting ready to regear LJ with auto trans. As many have mentioned, in current stock 3.73 and 34” tires, I click OD off every time I start driving. My question is will 5.13 (lowest I can go with Dana 30/44) be enough for 35”? Doing lockers and upgraded axles front and rear. Based on my math, 5.13 will gearing will result in 3.54 ratio (5.13x.69 OD). With the 34” and OD off (3.73) rpms are around 2700 at highway speeds 70mph. So with 3.54 gearing and 35” rpms will drop probably 200-300 rpms at same speed. Anyone with actually feedback?
alternatively, I could keep OD off all the time and regear to ??
appreciate all feedback.
alternatively, I could keep OD off all the time and regear to ??
appreciate all feedback.
5.13 will be fine, but you'll still want more. Even 5.38 with 35s and I felt like I wanted more.
However, turn the OD off anytime you start the vehicle and then the 5.13s will be perfect.
Get in that habit of turning the OD off and you'll be just fine, plain and simple. Don't look into it anymore than this, as there's nothing else you can do short of swapping in a different transmission.
5.13 with OD off, so 3rd gear would be 27% lower gearing, rpms would be approx. 3,400 for the same highway speed of 70 mph? Am I missing something?
If you ignore and never use the OD, you effectively have the 3 speed 32rle.
35" MTR
32rh/33.875"/3.07=2284rpm @ 75mph
32rh/33.875"/3.73=2775rpm @ 75mph
32rh/33.875"/4.10=3050rpm @ 75mph
32rh/33.875"/4.56=3392rpm @ 75mph
If you merge onto the highway, you would probably want to use the OD except on hills and while passing. Generally the OD is not needed for city driving or driving below 55 mph. At freeway speeds it is useful, however. (Assuming deep gearing is installed.)