Gear ratio question

D

drdiesel12v

Dr. Diesel Performance
Joined
Feb 4, 2009
Messages
168
i currently have 4.10 or 4.11's in my truck. and im going to be drag racing on the weekends with it and still driving it on the street. i have seen several guys running 3.55's.

Just wondering what is better suited. i know i will get better mileage with 3.55's! lol

thanks guys
 
4.10's are good for towing and I think they'd be better in the 1/8 mile. 3.54 is a better ratio for daily driving and the 1/4 mile. To do the swap you'll also need to get the correct carrier.

Depending on your tire height you may even consider 3.31's.
 
i am going to be running 235/85r16 street tires. which iirc are 31's.

i was thinking about the 3.31's especially with the price of fuel for some better mileage.
 
Take an educated guess on your hp, find out your truck's weight, use the e.t./mph calculators, and choose the tire size and gearing for your goals accordingly.

I second what Brett said if you are going to regear look at even taller gears than the factory 3.54s i.e. 3.31s or whatever is available.
 
Where does one find taller gears??

Never found any gears taller than 3.54's. I thought I found 3.31's once but not upon searching again.
 
randys ring and pinion has them, im trying to figure out the best carrier. i want a spool, but i cant find one for 3.73 and down with 35 spline. or what would be a good posi or locker? what do the big boys use? i was thinking of buying a new open carrier with spiders and having my welding buddy make a lincoln locker. not sure. what else to do...
 
you can use a detroit locker.. i put one in my last dana 80 with 3.54 gears. it just has to be shimmed to make it fit with the thinner ring gear..
 
i thought the 4.10+ were thinner and 3.73- were thicker? how would one shim a 3.31 to fit on a 4.10 carrier?
 
if you think about it the ring is thinner because of the larger diameter pinion gear.. they used to make detroits for both but now only for the thinker gear carriers so we are forced to shim them in the thinner gears..
 
ya why would they continue to make parts that fit everything right.. detroit also owns arb so they same holds true for that locker also..
 
We run the grizzly locker and gears from Randy's. Really depends on rpm range. If running 12's at 115mph, then 3.73 will be great with those tires. If running 125mph+, then may want to go 3.42.
 
3.31's would put you at 120mph at 3000 rpm, so it's a great ratio for drag racing with a 31" tire, not to mention 70mph is right around 1750rpm.
 
i have 410's in my rig running mid 11's..i also am running 305/50/r20's for tires. what do you guys think would happen to my times running lets say 373's...vid down below.
 
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We run a detroit and 3.54s. 32" tire on the street and a 30" DOT tire on the track (2wd truck)
I wouldn't recommend a lincoln locker or spool for the street. Although people will tell you all the time, "I run a spool on the street without any issues!"
 
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