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gearing for 35's

1845 Views 22 Replies 14 Participants Last post by  535banshee
i just put a 4.5 lift on my truck with 35's
i want to change the gear to make up for the power lose when towing. i can go with 4.10 or 4.56. has anyone done this to thier truck and what gears did you use?
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I think you screwed up a bit on your math. The ratio of 6th has nothing to do with 5th. 6th is 0.62x4th RPM. No?

i see you have a 5.9 i have 6.7 with a six speed. the gear ratio is way different. the 68re is 1:1 in forth gear and .81 for fifth and .62 in sixth. all tire to gear charts are for 1:1 at 65mph. my tire size with 4.56 is 2852rpm's @1:1
then take 2852 x .81= 2310 in fifth
2310 x .62=1432rpm's in sixth at 65mph

stock is [email protected] 1:1 @65mph
2715 x .81= 2199rpm fifth gear
2199 x .62= 1363rpm in fifth @65mph

69rpm diff
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