jstnvndn
Junior Member
- Joined
- Sep 1, 2024
- Posts
- 1
- Reaction score
- 1
- Location
- Winnipeg
- First Name
- Justin
- Truck Year
- 1979
- Truck Model
- K10
- Engine Size
- 305
I have a Saginaw 4spd and 35 inch tires. I feel that when I start off in 1st gear that it is lugging and does not "feel" like a 1st gear start...feels more like a 3rd gear start...so I tried to assess my rear end gear ratio and the 1st gear ratio of the manual transmission. Here is what I found:
1. The rear end indicates a 3.08 - I rotated both tires in the back and counted a full revolution of the tires to the driveshaft revolutions. The shaft turns 3 times to 1 revolution of the tires...so I estimate that it is a 3.08 rear end.
2. With the transmission in 1st gear I rotated the engine 1 full turn and counted the turns of the driveshaft, which only turned about a quarter revolution, so I assume it would take another 3 turns of the crank to equal 1 driveshaft rotation...probably indicating that would be a 3.50 gear for 1st.
Given that I have 35 inch tires, with a 3.50 first gear and a 3.08 rear end would that recipe describe my situation? I have to slip the clutch quite a bit to move the truck out in 1st gear.
I think that by changing either the rear diff or changing the transmission ratios would solve the issue and make it more driveable.
1. The rear end indicates a 3.08 - I rotated both tires in the back and counted a full revolution of the tires to the driveshaft revolutions. The shaft turns 3 times to 1 revolution of the tires...so I estimate that it is a 3.08 rear end.
2. With the transmission in 1st gear I rotated the engine 1 full turn and counted the turns of the driveshaft, which only turned about a quarter revolution, so I assume it would take another 3 turns of the crank to equal 1 driveshaft rotation...probably indicating that would be a 3.50 gear for 1st.
Given that I have 35 inch tires, with a 3.50 first gear and a 3.08 rear end would that recipe describe my situation? I have to slip the clutch quite a bit to move the truck out in 1st gear.
I think that by changing either the rear diff or changing the transmission ratios would solve the issue and make it more driveable.
Last edited: