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There is a lot that goes into this when looking at off road performance, manual/auto, transfer case ratios. You can put to much gear in the vehicle though especially when it comes to auto's and I am going to pick on @Bob Sanders here. If I am not mistaken Bob has 5.13's, running 35 inch tires and has the 4:1 transfer case. He has a problem stopping the vehicle when in 4lo and first gear. The reason for that is below stall speed of the converter you are almost double the amount of engine torque being inputted to the transmission. The normal recommendation would be 4.56's. He can climb the side of a building be he can't stop it. If it was manual this would not be an issue or if he goes to 37's it should not be an issue.

In the end I think most of us regear because of larger tires killed our on road performance, that is where we spend most of the time.
 
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Well, I'm just thoroughly incensed and insulted! :)

Actually what I need is the bigger brake rotors. When the stock rotors die I will upgrade, but until then... neutral works fine too.

True... you can feather it out with a manual and a clutch.... but too much of that and you end up replacing clutches prematurely.
Of course I was not bad mouthing ya, just that to much gear and the torque multiplication you get with an auto can cause an issue. I am having to look at this because I will be moving to an auto whenever I pull the trigger on the V8, provided the state does not get in the way.
 

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The big brake kit is a good idea if you're going to regear... particularly with a v8 and/or 4:1 tcase. At some point though the size of the brakes won't matter. You get enough torque going and even the best brakes just won't hold you back, and that's when shifting in/out of neutral comes into play. It's not a huge issue... you just have to remember to have your foot on the brake when you do hit neutral.

I was watching a video of a guy with a 4 speed atlas. Of course he had a manual so he could feather the clutch out at any time, but just as a point of demonstration even with big brakes, he stuck it in low 4wd, and couldn't hold it back with 2 feet jammed hard on the pedal.
Surprisingly the 4:1 transfer case is not recommended for V8 swaps has it is not as strong as the standard transfer case. The standard case or the Atlas 3:1 2 speed case is recommended. This is for the LS/LT motors. The 5.3 is close to 300 ft lbs of torque just off idle and the 6.2 at 350 ft lbs. When you are crawling and have the most in torque multiplication you don't need a lot of gear. Also the auto in these cases have a 4.03 to 4.7 depending on the transmission you go with.
 

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Crawl ratio seems simple, the higher the slower you go and the more control you have. And this is true when talking about about just a straight gear calculations. But nothing is as simple as it looks. Things that have to be taking into consideration are tire size and engine torque output. And with a manual it is much simpler than an automatic. With a manual it really is just a simple calculation.

When talking about an auto thanks to the torque converter you get about twice the amount of engine torque below stall speed, the stall speed for the JK is about 1700 rpms or so I have read. Many times people talk about crawling at 1000 rpms for the best control. Taking the 3.6 that is about 200 to 215 ft lbs of torque. Now add the torque converter to the equation and we are putting into the first gear of the tranny 400 plus ft lbs of torque. Start to multiply gears and we end up with a whopping 31,683 ft lbs of torque out to the wheels, split by 4 and you have 7921 per axle. As Bob found out he can't stop that much torque with stock brakes. This is also why we see snapped axles shafts even with d60's.
 
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If you want to crawl just get rid of the Jeep and get yourself a Unimog. Over 3000:1 ratio, you can go 475 feet in an hour.
 
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