matthumes

I have an 05 fx4. i am thinking of lowering my gears as my new boat weighs almost 7,000lbs with fluids and gear. Am i right that i have a 10.25" rear end. My stock gears are 3.73 so I am thinking of going to 4.10........I assume front and rear must be changed at the same time??? I guess I'd like someone to tell me what all is necassary as I will be having this done for me..

What ere some of my options as far as aftermarket gears and what with installation am I looking at price wise??? Thanks for your time.

05 super

i'm not sure if the 10.25 came in anything but the heavy package, but maybe i'm wrong. i have the 10.25 on my 05 xl with the 7 lug wheels and the factory 4.10's. if yours has 3.73's, i'm wondering if you have the 9.75". looking through my manual, i can't find any 4.10's for anything but the heavy package. so if you don't have 7 lugs, maybe it's the 9.75. clear like mud?

blackbetty

i am pretty sure its a 9.75 but i could be wrong

matthumes

you guys are probably right, i was just trying to figure it out sitting at the cpu.....nonetheless whare is a good place to purchase gears online and what kind of install time & cost will i be looking at???

TMintus8

I was gonna buy 4.10's front and rear for my truck(9.75" rearend) from 4wheelparts.com. They were on sale for $570 with installation kits like a week ago but now they're like $700(figures) . Still free shipping tho.

TennFire-1521

As long as you dont use your 4-wheel drive, then you shouldnt have too. As long as you can confirm the Front diff isn't being used at all during normal driving. If you changed out the rear gears only, and not the front, the next time you use your 4wd, you'll be dragging the rear tires. If you have the money, I'd do them both at the same time, and add a locker. It'll save you time and headaches later on down the road.

matthumes

ok, my axle code is B6, which i believe is 3.73 limited slip which of course is what my window sticker read when i bought it. My rear diff cover is a 12 bolt pattern, looking at this site http://www.drivetrain.com/Fordtrkratio_posidata.html
my rear diff matches the 10.25 diagram closest but not exactly.....so i am assuming that i must have the 9.75 as someone posted previously (they are 12 bolt correct?)

at 4 wheel parts this is the package i am interested in:
97-Up Ford 9.75in. Rear and Ford 8.8 Reverse Front 4.56 Gear Package

• Rear Ring And Pinion Set
• Rear Master Installation Kit
• Front Ring And Pinion Set
• Front Master Installation Kit

$771.00

What should I expect in labor assuming this is correct, and I guess this tells me all Ford front ends are the 8.8

Thanks again for everyones time

f150bm327

I have a 2002 FX4 with a 5.4 and a 9.75". I replaced the gears with the 4.10's and a hypertech upgrade. I pull a 6600 boat. Big improvement. I replaced the gears myself. This reduced the cost.

TMintus8

How long did it take to do the gear swap? Any special tools? I was just going to have my buddy who's a Ford/Sterling mechanic do it, but if it's not too hard i'll take a crack at it.

obusnizzle

have someone did it for you. If you have to ask yourself what is involved, then dont do it.