Gear Ratio

Reply Subscribe

Thread Tools

Search this Thread

Feb 5, 2004 | 07:50 PM

Hillbillydeluxe

Thread Starter

Junior User

Joined: Jan 2004

Posts: 50

Likes: 0

From: Elk Horn,KY.

Gear Ratio

O.K. I know this is gonna sound stupid but here it goes. My 75 4x4 has had the third member changed.(long story) It doesn't match the gear of the front.( which has also been changed to a HP44) I always thought that you could jack up the truck and turn the wheel one revolution and count the number of times that the driveshaft turned and get close on the gear ratio. The problem that I have is that when I done that, the drive shaft only turned 1 1/2 times and I know that there surely to goodness isnt a 1.50 gear. I done this with one rear wheel scotched (no posi) Am I doing something wrong or there something crazy going on here? Any help would be greatly appreciated.

Feb 5, 2004 | 08:05 PM

fordman300

Senior User

Joined: Aug 2003

Posts: 330

Likes: 0

From: clarks mills, PA

double that because you only have one wheel off the ground and you get a 3.00

Feb 5, 2004 | 08:22 PM

Hillbillydeluxe

Thread Starter

Junior User

Joined: Jan 2004

Posts: 50

Likes: 0

From: Elk Horn,KY.

Thanks!

A guy that I work with said the same thing but another said that wasnt right so I wanted to make sure. Then I probably still have the 4:11 0r 4:10's in the front. It turned just a hair over twice. this truck was supposed to had 4:11 from the factory but the front axle had been changed sometime in its past. Thank you a bunch. I was hopeing that I had atleast a 4:11 or so in the front so that all I had to do was change out the rear gears.
Would these gears be o.k for 35"'s? It has 33" now but would like to go to 35 due to the amount of lift on the truck. I have a 390 with C6 trans.
Thanks a bunch, I really appreciate it!

Feb 5, 2004 | 09:18 PM

SoCalDesertRider

Postmaster

Joined: Dec 2002

Posts: 3,959

Likes: 9

From: USA

4.11 is fine for 33's and will work with 35's too. 4.56 would be better though. Go to www.precisiongear.com or www.ring-pinion.com and use thier gear/tire size/rpm calculators to experiment with different combinations.