4bangerjp.com
General Forums => The Mess Hall => Topic started by: jeepfourlow on November 16, 2005, 05:36:50 PM
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so i swapped out the 41 tooth gear in my yj today in favor of a 33 tooth gear to make up for the 33" tires i have. got this info from a calculator at http://www.jeeptech.com/javaAps/Speedo.html now i want to know if anyone else with 33" tires has swapped out the gear because im not too sure if it is accurate, seems a little too fast...oh yeah and i think this would be good for FAQ Jeffy
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It already is there. It's under NVG231 since it's a part of the transfer case.
http://www.4bangerjp.com/forums/viewtopic.php?t=447
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hey but the calculator is different from your chart! which one do i use? 33 or 36?
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Well, it sorta depend on the actual height of your tires. AT's or MT's. PSI and overall weight.
I used the jeeptech chart but it's off a bit when I used it. I'm using a 35T for my 35's and 4.56's. It's as much as 4mph off at speeds above 65mph. I think to go with a 36T or 37T to correct it.
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well i measured my tires and their actually a stunning 31.5 inches! supposed to be 33.......
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Most 33's start off at 32.3-5" or 32.5-6". This is dependant on AT or MT. If you can get the speedo to be accurate to about 1-2mph, then you're doing pretty good.
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Forgot to ask, what gears do you have?
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stock gearing, i ordered a 36 tooth gear
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Anyone know what speedo drive gear would be appropriate for 33" tires w 4.56 gears ( my 88YJ ) , or ........ 33" tires w/ 4.88 gears( my 94 YJ ) ?
The charts and calculators I've seen are showing different results , I'd like to go buy a couple of drive gears , and do this one time only .
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http://www.4bangerjp.com/forums/viewtopic.php?t=447
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Great article , valuable information and good suggestions for upgrade possibilities. The chart shown suggest's I need a 39 tooth and a 41 tooth , however , ........ when using the calculator @ jeeptech.com , that produces a 37 tooth count and a 40 tooth.
Confirmation of what is going to be best would be nice , so I can arrive at the most accurate results.
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Well, if it was me, I'd go with the chart. Although the Java calc is as accurate as the data you enter. I've got 35's and 4.56's with a 35T. It's a bit slow at higher speeds. Below 60, it's only off by 1-3mph. At over 70 it's off by 4mph. It's progessive and not an exact 4 over the whole range. I should have went with a 37T I think. My stock is a 41T though.
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What I should have done , .......... Duh ............. I put slip yoke eliminators in both Jeep's this year , did I count the gear teeth when I had the drive gears out ? , nope ! . It won't take long to pull them and get a tooth count .
The 88 had 3.54 gears , last month I swapped in a pair of Dana 44 axles from an 87 Grand Wagoneer , rebuilt them through out , brake overhaul , 4.56 gears , Detroit locker out back and a Detroit tru trac in the front w / new Warn hubs. The rims are now six bolt , the old rims w/ 33" tires went on the 94 YJ , which got rebuilt from end to end ( long story , to be discussed later ) . The larger tires kinda killed the power , so.......... I pulled the 4.10's out and the open rear diff , installed a tru trac and 4.88's , front and rear.
I'd like to know what speedo drive gears I have now , I'll check in the next few days , once I know , I'll decide what gears I will buy , maybe one of the gears I already have is the correct tooth count , e.g. the stock drive gear for the 94 would work in the 88 , we'll see , .............