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Discussion Starter #1
i'm wondering what your rpms are in 5th gear at 70 mph.
state rear end ratio, and tire sizes, please.
 

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2300 RPM, 33X12.50 tires, 4.10 gear ratio
 

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285/75/R16

3.54's

2000 RPM @ 70 MPH

:peelout
 

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Discussion Starter #6

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Just for some info my auto, 37s and 4.10s I'm right around 2k at 70.
 

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Not sure of my gear ratio's but I have 315's. 2k at 70 mph.
 

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I DONT BELIEVE IT!
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with 410's and 37's right between 1800/1900:thud:
 

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5th gear rpm @ 70

just over 2000 at 70 mph in OD 5th. but i havent figured the larger tire size. im closer to 75 at this point I think. 3.54`s and I wish I had double Over Drive sometimes on the open road. :w: I cant wait to unlock my front end from 4wd. I want free spin hubs bad ! :hyper: :$:
 

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Discussion Starter #12
just over 2000 at 70 mph in OD 5th. but i havent figured the larger tire size. im closer to 75 at this point I think. 3.54`s and I wish I had double Over Drive sometimes on the open road. :w: I cant wait to unlock my front end from 4wd. I want free spin hubs bad ! :hyper: :$:
yeah that's kind why i was asking. i have the 3.55's and 285 75 tires and i just thought that 2000 rpm's is kinda high for just cruisng down the freeway.
with the stock 245's, it has tobe around 2200. hell, the truck runs out of breath at 2600!

the 28'5s are about 7.7% larger than stock whichwould put us at about 75 mph with an indicated 70. so i guess if we drop back to an indicated 66 or so, that would make us a true 70 and rpms would go back to 1850 or so.

i'm considering some 35's to lower the cruising speed rpms, but i wonder if the extra drag and weight would offset my fuel mileage gains from lowering the rpm's.
 
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