Gear upgraded, 3.08 to 4.10
I just upgraded the gear in my Suburban from 3.08 to 4.10! Still need to go to a speedo shop to get the speedometer calibrated. First drive today, it's feels quite a bit more responsive though it's...
Forum Discussion
While there are some ratios that are similar after the gear swap, it matters which transmission gears you're talking about.
For example, using the numbers from the 3.08 column above, the jump from 2nd to 3rd is 50% a increase in road speed for a given RPM. The jump from 3rd to 4th is only 33%.
This means 3.08, 3rd gear is like 4.10, 4th gear (both ~4.84:1 overall ratio).
So if you're pulling a hill in 3rd with 3.08 and need to shift down to 2nd, your engine rev's 50% higher after the shift. With the 4.10 it's 33% shifting from 4th to 3rd. That's a closer spread for the same road speed and more desirable.
In short, it's not the same to simply "run a gear lower" because reality means there's only 1 or 2 transmission gears that actually matter when pulling a grade for a given speed with a given rear end gear ratio. What this also means is that lower rear gears may not automatically be better if it changes you to a shift point that is wider than where you were at before.
For example, using the numbers from the 3.08 column above, the jump from 2nd to 3rd is 50% a increase in road speed for a given RPM. The jump from 3rd to 4th is only 33%.
This means 3.08, 3rd gear is like 4.10, 4th gear (both ~4.84:1 overall ratio).
So if you're pulling a hill in 3rd with 3.08 and need to shift down to 2nd, your engine rev's 50% higher after the shift. With the 4.10 it's 33% shifting from 4th to 3rd. That's a closer spread for the same road speed and more desirable.
In short, it's not the same to simply "run a gear lower" because reality means there's only 1 or 2 transmission gears that actually matter when pulling a grade for a given speed with a given rear end gear ratio. What this also means is that lower rear gears may not automatically be better if it changes you to a shift point that is wider than where you were at before.
