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Andy4639 · 01-20-2021, 06:44 PM

Turning the wheels and watching the drive shaft is about as close as you need. It will be dang near perfect for figuring out your gears. If it only turns 3 times you know it's not a 4:11 set!

If it turns 4 times you know it's not a 3:08 set. So with that being said if you turn it 3 1/8 times then it's got to be a 3:08.

3.07 gears were installed in automatic trucks. 3.73 gears were common in three speed trucks, and 4.11's were found with granny geared four-speed trucks.

This isn't gospel seeing how my 71 has 4:11 gears and it had just a normal 3 speed in it when I bought it from the original owner. But it's the only gear sets they used back then for the common truck.

01-20-2021, 06:44 PM	#7
Andy4639 Old member Join Date: Jan 2002 Location: Liberty, & Garden City S.C. , U.S. Posts: 19,945	Re: Help reading rear ended gears Turning the wheels and watching the drive shaft is about as close as you need. It will be dang near perfect for figuring out your gears. If it only turns 3 times you know it's not a 4:11 set! If it turns 4 times you know it's not a 3:08 set. So with that being said if you turn it 3 1/8 times then it's got to be a 3:08. 3.07 gears were installed in automatic trucks. 3.73 gears were common in three speed trucks, and 4.11's were found with granny geared four-speed trucks. This isn't gospel seeing how my 71 has 4:11 gears and it had just a normal 3 speed in it when I bought it from the original owner. But it's the only gear sets they used back then for the common truck. __________________ 1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver Seeing the USA in a 71 Upstate SC GM Truck Club 2013,14 and 2016 Hot Rod Pour Tour http://upstategmtrucks.com/ Get out and drive the truck this summer and have some fun! It sucks not being able to hear! LWB trucks rule, if you don't think so measure your SWB! After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.