Anyone have 4:10's?
 

I wanted to hear your opinions on gear changes from those of you who have switched your gears to 4:10's. Are you happy with the difference? For me the motivation is more for increased acceleration since I really don't do any towing.

I also wanted an idea of what kind of RPM's you guys are actually turning on the highway.

I've done the calculators online and according to them my truck would be running around 2400 at 65mph. I've got the 302 with the 5 speed, 2wd, and 31" tires.

If you say you have 31" tires then I would think the rpm would be lower. I have a 85 I just put a M50D in with 3:55 gears so I can't tell you what it will be from my truck, but from my mustang and using most of the popular gears I am pretty sure your rpm will be more like 1900 to 2100.

According to the manufacturers' published data (not an online calculator), those tires roll at about 680 per mile so at 65:

680 x 4.11 x 0.80 x (65/60) = 2422 RPM. The calculator you used was much closer than most.

You don't say what gears you have now. If you have 3.55s, the performance gains may or may not be worth the cost and effort of re-gearing, only you can decide on that; if you have 3.08s make the swap at least to 3.73s or to the 4.11s you're looking at

Thanks for the calculation. I do have the 3.08's so, from what I'm told, the difference between them and the 4.10's would be pretty noticable.

3.08s and taller tires are a bad combination. What you have now is roughly equivalent to stock tires and 2.73s. That's not only terrible for performance, it's not enough gear for decent fuel economy anywhere except the interstate. You may not want to go all the way to 4.11s, they will end up costing you fuel mileage. 3.55s would be about equivalent to 3.31s with stock tires and should deliver quite a bit more of both performance and economy, 3.73s will shift it more towards performance and the 4.11s even moreso.