Does Troyer Performance offer this, or can a find a quality set myself? Is it hard to install? I want to make sure my odometer is reading accurately and I'm getting all the power and efficiency I can from the motor and larger rims/tires, as it does with my stock 17's. I read somewhere that if you go to larger tires and stick with the stock gear ratio setup you will not get power and efficiency, you will get an inaccurate odometer and you will waste gas.

 

What is your stock size?

That is a 33" tire which isn't that large for stock gears. Peopel have been doing that for years on F-150's. Changing gears is costly (for 4wd).

 

I recommend 4.10s minimally. If you're intended usage is performance, towing, or off-roading and highway mileage is secondary, I recommend as high as 4.56s.

 

So are your saying it's okay to keep the stock gears right for my proposed setup, which would keep the odometer accurate, power and fuel mileage optimal?

 

I agree, your truck should have 4.10"s right, if it does that fine to run 33"s i run 35"s on my 01 and I have 4.10'"s its all good. If you take proper care of your rig it"ll be ok..Those big rimms will be a lot heavier though, you will probably notice it a bit on your gas milage, but not a huge deal...

 

I have that size on my Expy with 3.73 gears. They are only an inch taller than my OEM tires and I'm happy with the performance.

 

How would I be able to tell what gearing I have on my 2005 STX? I would probably need to call the dealer and speak with a mechanic.

 

You got some nice rides there man!!

 

I'm saying try it before you assume you need to spend $1500 on gears. No, the larger rims will be heavier and 33" is taller than stock so your speedo will be off, but probably not much depending on what the OEM tire size is.

What is your truck? 4wd STX? That means probably 3.55 gear, 255/70R17 tires, and 4.6L engine. I'm with Max Mitchell on the 4.10 to 4.56 recommendation now. I think you'd be happier with performance using 305/40R22 instead.

Check the driver's door for a plate that lists the axle code.
19 = 3.55 open
H9 = 3.55 LSD
26 = 3.73 open
B6 = 3.73 LSD
27 = 3.31 open
18 = 3.08 open
25 = 4.10 open
B5 = 4.10 LSD

 

For what it's worth, I run 4.10's on street wheels/tires (285/60R18) and I think this is one of the best upgrades I've done.

These trucks are geared way too tall from the factory, IMHO.

 

APT,
I have the 4.6L, 3.55 Non-LS. My plans are for 33's and a 6" lift. Would you recommend upgrading to the 3.73 LS Diff? The LS upgrade is to avoid 1 wheeling it in the sand. Would this offset the engine strain from the lift or compound it? I run straight pipes and have CAI with MAF upgrade--no chip.

 

My truck is the 2 wheel drive STX 4.6 Liter Engine. I will go and check the door.

 

It's says 19 on the door label. So you suggest the change to 4.10 right? When I upgrade to 305/45/22's? What about a recommendation on the width of the tire? I don't think 9.5" or 10" would make all that difference, I just want to make sure it doesn't rub anywhere?

This will be used 98% of the time for street use and going to the beach to go scuba diving, so some sand and dirt travel, but that's just to get in and out, depending on beach location.

Where can I go to get this gearing change done? Any idea on the cost of the part (brand/quality) and labor, can't I get the Ford dealership do it, or would that void the warranty should I go anywhere else or change out the factory part?