I am looking at putting gears in my supercrew 2wd. I tow a 25' pontoon boat when loaded is 5500lbs. I am running 285/50/20's which are right at 31" and I will be going to 305/50/20's which are 32". what I need to know is from some of you guys who are running these gears what are your rpms's at 70 mph? and what size tire you are running? I am mainly getting these to improve my towing but I WILL be playing on the street also . I am turning right around 1800 or so with my 3.55's at 70 mph.

any info would be great.

Thanks
Jack

 

I'd say get the 4.10s unless you plan on 'playing' a lot on the street and you want to get traction bars among other things.

 

I am making a set of caltrac traction bars for the truck since I cant find anything else that I like. so traction bars are going on it. I just dont want to spend money for the gears and be disapointed. My wife has 3.73 gears in here 05 supercab with 275/55/20's and it just doesnt seem to have the get up and go as my truck.

 

I just had a set of 4.10's put in my truck. Let me begin my saying they work out GREAT with my 285/60/18's (31.5" tall). I went from 3.55's -- which were great on highway, but sucked around town. Now for the problems:

I had Ford install my gears. My truck is an '05 FX-4 4WD. I thought Ford would be able to get everything 100% correct: no gear whine, quality job, OEM parts, correct speedo. Well, they did all of that, EXCEPT my speedo! 4.10's were not an option in the F-150 with a 9.75" ring & pinion until '06. Ford has NO way of correcting your speedo. I was forced to buy an Edge, which I was just able to get my speedo -vs- GPS within 1 mph.

If you have any more questions about this feel free to ask. Ford did a great job on the gears, but without a tuner (or a 2006) there is no way to correct your speedo without an aftermarket tuner.

After installing the Edge and setting it to level 2 the truck feels soooooooo much better. Shifts are nice, hard & quick, no throttle lag and when you hit the gas you MOVE.

 

Weaseled, I don't know how much truth really is in what you're dealer told you. Because, you'd be amazed with what Ford can do with their systems. I know a few mechanics and trust me, their trucks are pretty nice for 'stock'

 

I went around & around with them on this. I even called a couple of their 1-800 numbers. The reason given was that the truck could not be reflashed to 2006 because of a difference in emissions.

As I stated in my previous posts: they were going to pay Daytona Auto Air to put a calibration box in line with my speedo signal wire to correct the problem (which was going to cost them $225 on a job I paid under $1,300 to have done). He did say that he was able to input all the calibrations he wanted to use, but when he went to actually update the PCM it wouldn't allow it for some reason.

I'm happy it turned out this way though... The Edge kicks, and I got a set of Ford's 20" rims out of the deal for super cheap! I just need to find out what I need to do to fit a set of 33's on my truck. I want to use the 20's (the nice Alcoa ones), but I don't want to lose a ton of sidewall since I do drive on the beach & in mud a lot.

 

Well I'm not running these tires or gears but I just punched in a few numbers on my calculator for you. With the ratios below, I get the following RPM for your 32" tires:

3.55 ---> 1827 RPM
4.10 ---> 2110 RPM
4.56 ---> 2347 RPM

 

I would go with the 4.56s all the way. You will lose 1 mpg highway and gain everywhere else.

 

I'm not trying to hijack your post, Huitt24, but its along the same topic. I had planned on installing 4.10's next weekend but after reading the response to your post I am debating between 4.10's or 4.56's. I have the same scenario as you other than i don't tow anything. I'm strictly looking for a gear change for playing in the street! I am running 305/45/22 which are right at 31" also. So, my question is: would i also be better off getting 4.56's? Or is he just better off with them because he tows? Thanks

 

I wish there was some sort of way to change gearing as you drove, it's not too difficult to imagine a way for the differential to swap gears, but it's probably been attempted before. I'm sure down the road this is going to happen.

 

thanks for the response's guys it will help me. weasled, I am going with a tuner to adjust for the gears I am just not sure on which one(internal debate on what I want out of a tuner, edge ,diablo, tp excalII) thanks for the input about the dealer. Deerfeedrb thanks for the RPM info that is very helpful. Shane_Wilson no problem on the highjack thats why we post

 

305/45/22 is a 33" tire, or a 32.8" to be exact.

 

Thanks for that info. Ok, so, with 33's then I still ask the same question. 4.10's or 4.56's?

 

Get the Gear's 4.56

 

This coming from the guy who destroyed his leaf springs due to 4.56 gears on 31" tires, ha.