I am revealing my ignorance here. I have a 1966 C-10 with a 12 bolt rear end. It has a 283 with a standard 3 speed transmission. Does anyone know the gear ratio that came stock in these trucks. I am going to swap the gears for something that is a little bit better for top end. I don;t really need the low end power in this truck because i have another 66 C-10 that I use for towing. Thanks for any help Brian
It's a good bet that it is probably a 3:70 or a 4:11. Check the left axle tube for casting numbers. That will tell you what it came from the factory with. Or, with the rear on jackstands, turn the left rear wheel one rotation and count the number of times the drive shaft rotates. Do the math and arrive in the ball park of your ratio. For your 3 speed manual, I would not go any higher than 3:30. Dval
If I get the casting numbers from the axle tube wwhere can I look up the information to find what it has in it?
Hi Brian, You can also go to americanclassics.com and enter your VIN to find out what axle ratio was shipped from the factory. Tom
Alright this past weekend I put the beast up on stands and spun the rear tire one time. The driveshaft went around almost but not quite twice. According to my calculatons that is a 1.8 : 1 ratio which seems ridiculous. What is wrong with my math?
since you are not spinning both wheels,you have to double the number.that would make it 3.6 which probably is a 3.73 like most.
