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Blackcypress-EB · 12-07-2006, 08:33 PM

The quick on the truck way is to mark your tire on the sidewall close to the ground with a grease pencil. Then mark the drive shaft lengthwise as well as a mark on the pinion to line up by. Jack up the truck where the tire will spin. Line up the mark with the mark you put on the pinion. Turn the tire until you make one revolution with your driveshaft. Count how many times and the percentage of one revolution past the mark on the ground the tire turned for one rev. of the driveshaft. That is your gear ratio. This is not extremely precise but will get you within the ballpark of what gears you have. 3.73, 4.10and so on.

Gears out of the pumpkin are easy. Count the number of teeth on the ring gear and divide by how many are on the pinion gear.

12-07-2006, 08:33 PM	#14
Blackcypress-EB Registered User Join Date: Dec 2006 Location: College Station, TX Posts: 152	Re: New guy from Spring,Tx The quick on the truck way is to mark your tire on the sidewall close to the ground with a grease pencil. Then mark the drive shaft lengthwise as well as a mark on the pinion to line up by. Jack up the truck where the tire will spin. Line up the mark with the mark you put on the pinion. Turn the tire until you make one revolution with your driveshaft. Count how many times and the percentage of one revolution past the mark on the ground the tire turned for one rev. of the driveshaft. That is your gear ratio. This is not extremely precise but will get you within the ballpark of what gears you have. 3.73, 4.10and so on. Gears out of the pumpkin are easy. Count the number of teeth on the ring gear and divide by how many are on the pinion gear.