Gear Ratio for 35's on 1999 TJ 4.0?

if your use is really going to be around town and off road I wouldn't hesitate to do 4.88's. if you're going to be making long highway trips with sustained speeds of 75 mph I'm still at 4:88's


Edit: just saw this post, Dana 30/35 both max at 5.13, as far as I know. Revolution has the gear sets. so I would do 5.13's if that's the case
 
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I have 4.56 gears with 35" Patagonia MT's and I'm pretty happy with them, especially since I have to drive fairly long distances on the highway to get to a Jeep playground. I wanted to keep my highway rpm range closer to 2,400 and it worked out well for me. I only downshift to 4th gear when I'm going up some of the steeper grades on Hwy. 80 or 50, which is not a big deal for me. If you really want to hear what it would be like to go with 4.88 or 5.13, just downshift to 4th and bring up the rpm's to 2,800 or 3,000 so you can determine if you could live with that for extended periods of time; yes, peak torque is at those rpm ranges, but so is noise and vibration. No right or wrong, it is a matter of personal preference (within reason). If you check the roster for the upcoming Rubicon Trail trip, you will find several Jeeps on 35's who have 4.56 gears and you can also ping those folks for their opinion. Only thing I will change as soon as I do the tummy tuck on my Jeep will be to replace the annoying Borla muffler and get rid of the drone by choosing a quieter muffler.

btw, even though it's technically not legal in California, I use my Bose QuietComfort noise cancelling headphones while going down the road with mud tires and the difference is unbelievable; you will not be nearly as tired when you get to your destination because the constant noise just wears you out a lot more without the noise cancelling headphones.
 
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I will politely disgree, your recommendations chart should show a range of gears, not absolute numbers. You should also post the torque curve of the engines; for example, the inline six 4.0L has an extremely flat torque curve and as long as you don't fall below 2K rpm or so, it will pull several different gears just fine. Until I re-geared, I had 35's with 3.73 gears and I assure you that it's painfully obvious that it's geared way to tall.

A lot has to do with the type of terrain you drive, whether you have to knock out hundreds of miles on mostly flat land or if you're constantly on very steep mountains roads, hardly ever on highways. The gear ratio is far more important for the street than it is for trails because changing the transfer case ratio for wheeling from 2.7:1 to 4:1 is more dramatic than any gearing change.

4.56 is the tallest gearing you would want with 35's and 5.13 would be at the opposite end, but they'll both keep the engine spinning in a reasonable torque range. For a trailer queen, 5.13 would be a no-brainer but if you caravan hundreds of miles down 70 mph highways (where all my buddies drive 75-80 mph), 5.13 gears would suck donkey balls (at least for me).
 
I will politely disgree, your recommendations chart should show a range of gears, not absolute numbers. You should also post the torque curve of the engines; for example, the inline six 4.0L has an extremely flat torque curve and as long as you don't fall below 2K rpm or so, it will pull several different gears just fine. Until I re-geared, I had 35's with 3.73 gears and I assure you that it's painfully obvious that it's geared way to tall.

A lot has to do with the type of terrain you drive, whether you have to knock out hundreds of miles on mostly flat land or if you're constantly on very steep mountains roads, hardly ever on highways. The gear ratio is far more important for the street than it is for trails because changing the transfer case ratio for wheeling from 2.7:1 to 4:1 is more dramatic than any gearing change.

4.56 is the tallest gearing you would want with 35's and 5:38 would be at the opposite end, but they'll both keep the engine spinning in a reasonable torque range. For a trailer queen, 5.38 would be a no-brainer but if you caravan hundreds of miles down 70 mph highways (where all my buddies drive 75-80 mph), 5.38 gears would suck donkey balls (at least for me).

Where would you like to see the rpms at 75mph on flattish ground?
 
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I will politely disgree, your recommendations chart should show a range of gears, not absolute numbers. You should also post the torque curve of the engines; for example, the inline six 4.0L has an extremely flat torque curve and as long as you don't fall below 2K rpm or so, it will pull several different gears just fine.
I couldn't disagree more.
 
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