Gear ratios

[AussieinNC]

Here is a link to an online calculator, using trans type, rear gear ratio and tire height...makes it simple

https://www.blocklayer.com/rpm-gear

Using your 3.08 gears, I get around 1590 rpm and 70 mph.....engine better have some deep torque curve for this to work ok....

Leave the 4.11 gears in it for a decent driver....

[Ziegelsteinfaust]

Update.

I just did a 1000 mile trip with 31" tires, 2500 rpm stall converter, and close to 800 pounds in the bed. Along with a roof top cargo carrier mounted above the bed height. While I had a head or heavy cross wind nearly every time I hit the highway. It was still better on mpg then the 4.88's did.

The only downside was the converter. As it flashes to high for that kind of load.

Today I had to put new tires on since my 285/65r17 were to wide for the new rear axle. 235/60r16 front and 255/60r17 rear. They stretched perfectly to my rims, and look better then I hoped.

So the rear tires are considerably lighter then the old ones, and measured height is 28.5 inches. The truck now feels more then fast enough empty for a DD, and well it did handle the old tires with weight good enough. Atleast for a temporary fix.

Unfortunately my fuel pump died this morning, and I only drove with the new tires for 10 miles.

Will do another update when I fix the pump this weekend.