Right now I am saving for a 5" RCD and 3" PA body lift. At that time I will go with 35" tires and 4.10 gears. I was wondering if I went with 36" tires, should I get 4.30's? Also, how close to stock is 4.10's with 35'' tires as far as speedo correction etc. What about 4.30's with 36"s? I want to get it right the first time since I am going to do everything at once. Thanks.

-Matt

 

4.10 is fine all the way upto 37's i am not sure why you would run a 4.30 i am not sure that is even available for your truck, but either 4.10 or 4.56 would be a good choice 4.10s should run like stock on 35s or 36s even but the upgrade for a little more power and torque off the line i would run 4.56

 

Thank you for your input. It appears that 4.10's should be sufficient. I am running a blower on my truck right now, so I have a ton of extra HP and Torque over stock. Very soon I will be putting around 400 HP to the pavement, so I don't want to break any of the other drivetrain. Just trying to make the most educated decision about my setup. Thanks.

-Matt

 

4:10s would be perfect for the 35 and 36s. I run 3.73:1 with 35s and it still works great.

kev

 

If you still have any doubts check out:

www.ring-pinion.com

There are a few calculators on the site with one specifically for calculating RPM with different tire sized and gear ratios. HTH

Here's the link to the calculator page:

www.ring-pinion.com/calculators.shtml

 

4.56 gears would be the better choice with 35 and taller. I have 35's on my truck and if you do the math to get back to a 3.55 you need more than 410's. I have the stock 3.55's so that puts me at or around 3.09's I can still get around ok but if you have a load or up big hill you know it. Im upgrading to 4.56's after xmas and my truck is a 2001 so I have to change the spedo malfunction with a chip.
and its no problem finding gears if you dont have the 5.4 you a 8.8 with 31 spline axels. pick up any 5.0 mustang book and there everywhere.

Dale

 

here is a picture of my truck with 35's

if this works

 

Thanks mr2x75,

I think I have 3.73's right now, because in 3rd gear (direct drive) on 33" tires at 60 mph I am turning about 2300RPM's which calculates to 3.73's. I need to finish my next round of mods too to see what kind of low end improvement I see. If I want more, then I will have to jump to 4.56's when I lift it. Thanks again.

-Matt

 

This might help too http://www.dakota-truck.net/TIRECALC/tirecalc.html