newbie gear selection question
11-18-2010, 10:42 PM
#1
Member
Thread Starter
newbie gear selection question
I have searched and i can not find out what gears i should choose to run with my set up.I see alot of guys run the 4.56 gears with 35 inch tires.My set up is 35 with stock gears and i have the roush supercharger.I called roush today and they said with it being blown they would not recommend runnning that much gear.They said to stay in the 3.73 or 3.90 range nothing more then 4.10.They said the rpm would be way to high for highway use.The truck is my dd.So what do you guys think?
11-20-2010, 10:17 AM
#4
TSR Motorsports
Join Date: Mar 2010
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what kind of driving are you looking to do? (city, highway, mixed, little towing, a lot of towing, towing near limit weight)
the amount and type of driving will be the ultimate decision on what kind of gearing you want to go with. do you know what gear ratio you have stock?
the guys with large tires and high gear ratio do that for off roading capabilities only, and they usually do not run a supercharger. they run the higher gearing as they do not run at very high speeds and use it for crawl speed. the higher the gear ratio the lower the max speed of the vehicle.
use this calculator to figure out what you want to do:
http://www.grimmjeeper.com/gears.html
if you run the high gear ratio with the supercharger, you will burn through a set of tires in the blink of an eye. i would recommend staying in the lower 3's for a good mix of highway driving and still have enough power to accelerate. if you do more towing and require more torque in the lower rpms's, then go with the higher 3's for a gear ratio.
the amount and type of driving will be the ultimate decision on what kind of gearing you want to go with. do you know what gear ratio you have stock?
the guys with large tires and high gear ratio do that for off roading capabilities only, and they usually do not run a supercharger. they run the higher gearing as they do not run at very high speeds and use it for crawl speed. the higher the gear ratio the lower the max speed of the vehicle.
use this calculator to figure out what you want to do:
http://www.grimmjeeper.com/gears.html
if you run the high gear ratio with the supercharger, you will burn through a set of tires in the blink of an eye. i would recommend staying in the lower 3's for a good mix of highway driving and still have enough power to accelerate. if you do more towing and require more torque in the lower rpms's, then go with the higher 3's for a gear ratio.
11-20-2010, 11:35 AM
#5
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Thread Starter
I do mostly city driving, not a lot of highway driving, and I have a 93 civic hatch that I tow. The gears are the stock 3.55. That is what the tags on the rear end say. I bought the truck how it is so I am not 100% sure if they are stock. The truck just seems to shift a lot when I have the o/d on in the city when cruising at 35 mph. So is it really worth doing gears if I only go with the 3.73? I talked to a few people and they said the 3.90 would be good. But I don't think they make them for my truck? So would the 4.10 work ok? I have the 9.75 rear axel and the 8.8 front.
11-22-2010, 10:20 AM
#6
just to give you an idea on your RPM's, with the 4.56 and 35's, i run about 2200 at 65 mph. that might be what rousch is worried about, prolonged high end RPM.s now, what you choose is totally up to you, but i think that if you take their advice and go with 4.10, being blown you still shouldnt have any problem. however, the cost just in parts for front and rear was about 1000.00, i did the install myself.... i was quoted almost 2500.00 for parts plus install front and rear..... that might make it not so cost effective for you.
when i swapped to my 4.56, it definately makes the truck drive much better, and way less shifting.
when i swapped to my 4.56, it definately makes the truck drive much better, and way less shifting.