Good point . I guess I’m thinking stock to stock.
I also think anyone can/ should build for their terrain if needed....not on my or anyone’s mandate .
What's needed to turn my LJ into a near Rubicon?
- Thread starter TRevs
- Start date
I also think anyone can/ should build for their terrain if needed....not on my or anyone’s mandate .
I thought 4.10 was the stock differential gearing on late Rubicons.
I'm just starting to learn about re-gearing; I'd appreciate a link to a good write up if anyone has one.
Greenmachine
TJ Enthusiast
All this talk of lockers, gears, tummy tucks and whatnot, let’s be honest, all you need are Rubicon hood stickers.
The appropriate gearing has everything to do with the tire size and transmission. Whatever a Rubicon is does not matter, which I'll say is true for anything about how you want to build your Jeep.
This. The steeper 241 transfer case has zero downsides if you've got a manual transmission. Too short of gearing? You can take off in 6th. Turns out 6th in 4lo is right between first and second in 4hi, at least with the 6 speed like the OP has.
I can say from experience that having the 4:1 and a 6 speed and properly geared axles for your tires makes one hell of a versatile rig. I've been to the Outer Banks and driven to Carova, I've done mud, done rocks, done full throttle hill climbs. It's the best combo for a stick shift.
I can see where it would be super annoying in an auto, though. Me, I just decide essentially what ratio I want to take off in when I'm crawling and that's the gear I use...
For example, I was doing a smooth, but very steep, hill climb on my last outing. 1st gear in high (I'm geared 5.13 on 37s) would bog just before cresting, using all the run up space I had available to me. 4th gear in low got me to the crest. Then I went home and bought a supercharger lol
I may be a smart ass, but this time, what did I do?Apologies, I 100% thought JMT was being a smart assThis is on me.
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Yes, regear at the same time as lockers. With 33’s and the NSG370 you’ll want 4.56 gears. If you are ever contemplating 35’s, go with 4.88. I vote for Eaton E-Lockers front and rear if you want to be closest to a Rubicon. The good thing is you can run them in 2WD, 4wdH and 4wdL. But, since you live in SA, I know where you wheel, used to live there. Hidden Falls, Wolf Caves, a few others at times, you hardly ever see snow and ice, so you could run a PowerTrax No Slip Lunchbox up front. It’s an automatic locker, ~400 and you can DIY before or after the regear And save some coin if that’s an issue. They are invisible in 2WD.
I live in SA, but the Jeep is going to Colorado next month where it will live. Most of its trail-time will be in the San Juans. I bought it to get me to altitude and remote places the Explorers and RVs can't go.
I've looked a bit at the ARB and Eaton lockers; who sells the differential re-gear sets?
I agree; I'm not trying to reproduce a factory Rubicon. It's just a level of capability I want to approximate. Nothing extreme, but an upgrade from stock LJ.
You can’t really go wrong with either ARB or Eaton E Lockers.
Revolution is at the top of the game. I had Just Jeeps in Austin regear mine. I couldn’t be happier. Price was $450/diff plus another $200/locker. Took one day and they treated and broke in the gears so I could drive straight home. Wheeled it the next day. 12,000 mile warranty and I supplied the gears and master install kits.
Usually a shop requires that they provide the gears if they are going to warranty parts and labor
So with the NSG370 6 speed and 33" tires, what are some appropriate gearing matches with each transfer case?
If I stick with the 231, get 4.56 gears?
If I change to the 241, what gears should be in the differentials?
It doesn’t matter, 456 either way.
If you want to plug your data in and see the differences between different gear ratios, go to Grimm Jeeper.
4.56 minimum. I would consider 4.88 even for the 6 speed.
Transfer case is irrelevant when the idea is to gear for the highway. Though if people would gear correctly for the highway, they would automatically benefit off road with the lower gears that should be there in the first place.
Pick your gears based on street driving, that'll be a 1:1 ratio regardless of transfer case. I'd make a decision based on whether you think you may go to 35s in the future. 33s and 4.56s is perfect, but maybe a bit low if you go to 35s. 4.88s are a bit high strung with 33s but will be perfect if you go to 35s later. The heavier the tire the higher revs you want, rotational inertia is a bitch. And the more mountainous driving you do the higher the revs you want. Being slightly longer geared with the 6 speed isn't as big of a deal as it is with the 5 speeds or autos, since the step between 5th and 6th isn't really that big. Downshifting doesn't make your Jeep sound like it's going to explode.
For example, if you went 4.56 with 33s and later went to 35s, downshifting to 5th gear to get up a hill is only 3060 rpm at 70mph. It's very flexible still, you just might need to downshift a bit more often than with 4.88s.
examples
31s 4.10 = 2,610 rpm at 70 (stock Rubi just for comparison)
33s 4.56 = 2,730 rpm at 70
33s 4.88 = 2,920 rpm at 70
35s 4.56 = 2,570 rpm at 70
35s 4.88 = 2,760 rpm at 70
37s 5.13 = 2,740 rpm at 70 (my setup, easily did 70 in 6th even before it had boost)