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Discussion Starter #1
If i changed my rear gears, how many rpm would i be running at 70mph 80mph and 90mph?

I think my 3.42's run around 2000rpm at 70mph

3.73?
4.10?
 

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internet bigot®
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i cant remember, if i had my truck i would check for ya. there isnt really that much of a difference...

but i went from 3.73's to 4.10's...
 

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Discussion Starter #3
onyx said:
i cant remember, if i had my truck i would check for ya. there isnt really that much of a difference...

but i went from 3.73's to 4.10's...
Do you drive highway that much?
 

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a.k.a. turbodan
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ok this is what i got
3.73 gears,
70mph 2200
80mph 2500
90mph 2800

4.10 gears
70mph 2410
80mph 2755
90mph 3099

i did this with my automotive math book, so the numbers should be really close. i had to guess on the overdrive gear ratio though. i put in a .75 final drive and that got me where i wanted it too. pretty close anyway.
hope this helps
Dan
 

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fullthrottledan said:
ok this is what i got
3.73 gears,
70mph 2200
80mph 2500
90mph 2800

4.10 gears
70mph 2410
80mph 2755
90mph 3099

i did this with my automotive math book, so the numbers should be really close. i had to guess on the overdrive gear ratio though. i put in a .75 final drive and that got me where i wanted it too. pretty close anyway.
hope this helps
Dan
I think .75 is just about dead on from what I remember about the data I pulled from my tranny one time...either .74 .or .75...something like that.
 
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