Re-Gearing from 4:56 to 4:88
05-28-2016, 03:29 PM
#12
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I'm running 5.13's and 35's right now. I don't have any issues on the street at all. I rarely use 1st gear, but I'm fine with that, I'll give up 1st on the street for the control it provides in the rocks. I live in Phoenix AZ, while it's not the most populated city in the land, it sprawls forever. Driving for an hour does not get me to any wheeling spot, I am always on the road a min. of 1.5 hrs to get to wheeling terrain. Currently, 70mph is 2900rpm, 75mph is 3100rpm. With today's lightweight rotating assemblies, over head cams, and the VVT I'm really not concerned about the motor living at those rpms. It's not like we a are driving 1980's OHV V8's with 2lb pistons slinging around anymore. 37's, and I'm guessing here, would drop those rpms by ~200. Absolutely livable, and I'm betting the the added weight, that little extra tire diameter would make 1st more of an option on the street again. You say it's a 6spd(as is mine) so you do not have a tq convertor to help with the slow speed off road stuff. You really want to go as deep in the gearing as you can, yet still tolerate for road use. Like I said, when I go to 37's I'll be going to 5.38's. All of the above is based off the idea that you are going to wheel it in precarious situations... situations where most folks are going to look and say "there's no way a Jeep can go there". If this rig will be used more for light wheeling (body damage highly unlikely, roll over situations non-existant) then maybe selecting a gear set more focused on the highway is a better bet.
My 1st gear will then become better suited for creeping around in the woods. See....I rarely use 4-wheel low, so I can't take advantage of those lower ratios. I guess I could use it, but why be in low on flat, dry ground?
05-28-2016, 04:52 PM
#13
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I found a great gear ratio calculator that shows the difference between ratios with the tranny you're running......http://www.4ws.com/gear-ratio-rpm-calculator
Based on this, when I went from a 4:10 gear with 35's to a 4:56 with 35's, I made a 11.3% change. Figuring same size tires....if I went from 4:56 to 4:88 like I'm thinking, I'd see a 7% change. But if I went from 4:56 to 5:13, I'd come in at a 12.4% change (closer to what I felt when I went from 4:10 to 4:56). I don't think a 7% change is what I really want.
Based on this, when I went from a 4:10 gear with 35's to a 4:56 with 35's, I made a 11.3% change. Figuring same size tires....if I went from 4:56 to 4:88 like I'm thinking, I'd see a 7% change. But if I went from 4:56 to 5:13, I'd come in at a 12.4% change (closer to what I felt when I went from 4:10 to 4:56). I don't think a 7% change is what I really want.
05-29-2016, 04:34 AM
#15
JK Enthusiast
What about the back way to Crown King? Table Mesa RD has atleast 5 tough great trails... some of the best are closer than you realize...I've given that a great deal of thought.
Last edited by Mike H.; 05-29-2016 at 04:36 AM.