Ram 1500 v6 - axle swap 3.21 to 3.55

[Threesuns1]

Silver bullet,

I don't think what your wrote above is correct. With the 3.55 rear end, the engine is turning more rpm in every gear including 8th. That means it has more torque to carry hills. It is a minor point but in theory, I think the transmission will have less need to downshift. I think it's minor because the extra torque you need has to be quite small for this small change in rear end ratio to provide it. But the difference between 7th and 8th is also pretty small. I have not done the math.

But in each gear, a higher rear end ratio means more engine rpm and thus more torque.

Jim

I was under the impression lower rear gears meant more rpms at the same speed, 3.21's being higher than 3.55's.

 

[Richard320]

I was under the impression lower rear gears meant more rpms at the same speed, 3.21's being higher than 3.55's.

Lower gears = higher numbers. People get confused all the time over that one.

 

[JimD007]

The rear end ratio is how many times the driveshaft must revolve for the rear axle to revolve once. So with 3.21 gears, the driveshaft has to revolve 3.21 times for the axle to revolve once. With a 3.55, the driveshaft will rotate .34 times more. Not a big difference but it means the engine rpm will be higher as long as the transmission gear is the same. Higher engine rpm = higher torque (unless the engine rpm goes higher than peak torque).

 

[stormcom]

Just drop down a gear or two, it will be like a 3.55 rear end. transgear x axle ratio = engine rpm.

Save your money.