I've got a 05 STX reg. cab 4x4, 4.6 auto with 3:55's. Its got the 255/70's on it right now. I'm planning on a leveling kit and probably 35's soon. I think it would turn 33's no problem but i think 35's would drag it down a little to much for my liking. I went up two inches from stock on my deceased Ranger and didn't really notice it. I really want the look and extra clearance of 35's but dont really want to have to re-gear it. I haul/tow two 4x4 ATVs (1,000-1,200 lbs.) so that has to be considered too. Any opinions or experience is appreciated.

 

Here’s a quick look at what your gear should be with bigger tires

Gear Ratio Guide for Larger Tires

 

You're probably going to want to go with 4:56's if you get 35's.

 

*grrr* i hate that list. it reminds me that i need to re-gear *cryin'*

 

I regeared with 33's with a 5.4L. Guess it all depends how much off the line push you are willing to sacrifice (not to mention extra strain on parts from making them push harder to get up to speed).

 

hey, sorry to barge in, but can someone further explain that chart... ive got the 3.73 with the 31" rugged trails presently- looking to go to 35's now according to the chart, they say my rpm at 65 is 2628 (factor in 30% difference for OD), and thats 1800-1900 rpm (on my truck) so, when i look at the chart, do I want to match to the 2628, or the 18-1900? when i up to 35's so the 4.27s should be right. second question, what is prime- do you want more or less rpm?

thanks alot-
jj

 

Go cruise the highway at 65. Look at your RPM. That'll give you a good idea of where you need to be with 35's (use gearing that will come closest to matching that rpm).
That said:the majority of people who go 35's seem to go 4.56's

 

right...and cruising at 65 im under 2000 rpm i dont hit 2000 till about 73mph, and 80mph im about 2200

 

Well, 4.56s put me right at stock AND I have 37's.

If you go 4.56s with 35s you will definately get alot more pep off the line.

 

It might be hard to find 4.30's ... though it would be a nice gear to have ...

When I went to a 33" with 3.55 gears my truck was a royal dog ... yes it drove ok ... but wasn't FUN to drive! A simple ATV trailer required OD to be locked out most of the time on the highway. It would have liked to never hit highway speed with a real trailer hooked up.

After a few changes including gears ... it yanks things around quite fine! My Gear Chart That chart posted earlier is one of the good ones! Mine uses our OD for RPM's at 65mph vs tire sizes.

 

My truck drives great with the 3.73 gears, hell probally even more fun but I know its just in my head.

 

cool thanks guys

 

nice chart tycreek. from what I read on that chart my rpms tend to run about 2 to 300 rpm higher than that chart. so I am assumeing we are loosing arround 200 to 300 rpm in tourque converter slipping. so when figuring your target rpm you should be adding about 200 to 300 rpm.

 

sal- thanks so what size do i look for- looking at Yukons 4.30, 4.56 8"? 9"? etc. and does that include front axel too, or is that just for the rear?


oh and sal- love the tires, was actually considering them since toyos are on 2mo. backorder- how's your experience been with them so far? im sure they're noisy, but performance on and off (offroad cant be treating you too bad, those girls made it over!) and treadwear?
sorry, thanks alot


jj

 

studying those charts I think the best ratio for 33's would be 4.10 and for 35's would be 4.27. I think I heard someone mention once that someone makes a 4.27 rear gear for our trucks. I am not sure on that one though.