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04-17-2003, 07:04 PM | #1 |
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Gear ratio
Can someone tell me the procedure for figuring out rear end gear ratio? There are no stampings on this axel.
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04-17-2003, 08:32 PM | #2 |
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Heres what u do to go figure it out.
1. go for a drive and write down your RPMs at a few mph. 2. Measure your tire diameter. 3. go to http://www.smokemup.com/auto_math/rear_end.php and plug in the numbers you have from the drive and it will tell you. Hope this helps. HotRod
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04-17-2003, 09:59 PM | #3 |
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Thanks for the imformation
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04-17-2003, 11:21 PM | #4 |
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You can also just mark the tire and driveshaft, rotate the tire one full turn and count the turns the driveshaft makes....3.7 turns = 3.73. A little less than 3 and a half turns = 3.42
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04-18-2003, 12:42 AM | #5 |
its all about the +6 inches
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Or pop the cover off and look for the stampings, or even count the teeth.
Fresh oil in the rear diff ain't a bad idea anyways. |
04-18-2003, 12:45 AM | #6 |
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I think I checked mine by rotating 2 full turns. It's been awhile though.
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Jim 1970 C/10 Fleetside w/Ghost Flames Lowered 4.5" front and 4" rear (Raked) 355/350 Turbo w/shift kit 10" Redneck Performance Verter w/2500 stall Hooker Super Comps part#2808-1 Performer RPM Air-Gap 12 Bolt w/3:73 gears- Eaton Posi Comp Cams XE262 with 1.6 Crane Energizers, Road Demon 625 and Brodix IK 180 heads |
04-18-2003, 01:26 AM | #7 |
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I'm with andy on this. The best way to tell is to change the gear oil and count teeth while you're at it. The numbers will actually be stamped in the face of the pinion. Take the larger number and divide it by the smaller number and you've got your ratio.
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04-18-2003, 12:50 PM | #8 |
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If I remember correctly, turning the wheel only works if you turn both tires at the same time (at least for an open diff).
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04-18-2003, 01:07 PM | #9 |
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this place here will also help you figure out your tire diameter:
http://www.rx7turboturbo.com/robrobi...e_diameter.htm
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Mike 2001 Dakota R/T - Silver CC - 1 of 1671 •360 w/46RE •392 limited slip 1972 Chevy Suburban - Turquoise/Black 1969 Chevy C/10 - Blue LWB •350 w/ 700R4 •3.73 posi •PS PB A/C - SOLD Using your turn signal is not "giving information to the enemy" 67-72 FAQ |
04-18-2003, 11:37 PM | #10 |
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Thanks for all the great help. Got it figured out. I have a 3.73 positraction.
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