So I've been scoping out what it would cost for some of the future mods I will be doing to the truck and was looking at the price for the gear swap for the diffs. I've always heard that it was about a grand per axle but when looking at the replacement yukon 4.88 gears,
Yukon Gear & Axle/Differential Ring and Pinion (24570) | 2004 Ford F250 Super Duty P/U 4WD 8 Cylinders L 5.4L EFI | AutoZone.com
, is this all I need for a gear swap? I'm also planning on putting a locker in the rear at the same time, does this effect the gears I need at all?

Planning on running a set of either nitto 37x12.5 or toyo 37x13.5. Probably the Nittos since both are actually about an inch wider than they specify and my wheel is barely in the range for the toyo width. The Toyos are also a load range E while Nitto is a D, Nitto doesn't like 17inch wheels I guess since the 18inch has a E rating?

But for offroading, would it be better to have a D rating so the side wall will flex more when aired down? I've never ran this truck with anything but E rated so I don't if the Ds would be "squishy" on the road.

As a side note, I though it was funny that the 4.88 gears are about half the cost of the 4.30

Yukon Gear & Axle/Differential Ring and Pinion (24572) | 2004 Ford F250 Super Duty P/U 4WD 8 Cylinders L 5.4L EFI | AutoZone.com

Go big I guess.
5.38s are also only a 100 bucks more...

 

I'm getting 4.88s in the spring... I'm running 35 inch tires.

The jump to 5.38s and load E vs D, depends on how much/heavy you tow as well. But... with that 5.4 I would go big

 

Not much at all since it's being retired from commercial use. Currently it's just a DD so once I get a commute vehicle, this will be for fun/personal projects.

Planning on putting leveling springs in the front with a 350 block/springs in the back and cutout fenders, and then decide if I want a whole new leaf set for the rear. I get by pretty well with stock suspension and the sway bars still connected on 33s.

And then the biggest part of my plans for it is doing a short bed conversion. But I'm not at all confident enough in my skills to take it on. But I don't know anyone or any place that will do it so I've been trying to fab anything I can to get some more experience.

 

If you're sticking with 33's, and not towing much, then 4.88s will be plenty. 4.30s probably would work too.

Funny you mention the short bed conversion.... I've been tossing around the idea of making mine a long bed. I know some shops do frame stretches on semi cabs and tow trucks, so I'm sure it can done on a pickup. In fact, there is a place in Utah that does long bed conversions on Ram Megacabs.

 

I'll be going to 37s with the lift and cutouts. Haha well I've got a white long bed in almost mint shape.

 

ah... well with 37's then yeah at least 4.88s

lol well I'm still a ways out on the long bed thing. I want to get my gears done and tackle a bunch of other stuff first

 

On my prior truck ('03 F250 7.3) I ran 37" toyos with Yukon 4.30 gears, detroit locker in the rear, and dyna true-trac up front. I ordered everything from randy's ring and pinion on the interwebs- they will get you the right locker for your gears (thicknesses of the carrier vary) and bearing kits. I don't recommend the front limited slip - in the snow I had a wicked pull to the side on the highway in 4wd. Then I had a local truck suspension shop do the install.

 

I'm not planning on a locker or LS in the front, just one in the rear. I'd like for it be a selectable one as this will still be on the streets, but i don't really care for the ARB lockers as my friends that have them have problems with them freezing up and leaks more often than I'd like. Does anybody know of any other good selectable lockers?

 

Have you looked into Detroit Locker? We've had good success with them in the past. Not sure if they make anything specifically for your F250.

Also, 4.88 gears on 37's should offer enough "oomph" for DD.

 

No I haven't looked at theirs as I thought they were all sealed/standalone lockers. I'll take a look at their website tonight though.

When all of this is finished the truck won't be a daily driver, but I would like for it to still be street legal/capable. Is your avatar your truck?

 

Yup, it's our company's flagship truck. Based on Ford F550 but heavily modified. It'll stop 7.62 x 51mm AP bullets.

 

It looks impressive, what do those weigh in at?

 

The one in the picture is 16,000 lbs. The longer version of it weighs in at close to 19,000 lbs.

 

Detroit locker is perfectly streetable in a daily driver, especially in an F250. On my old CJ7 jeep, you had to warn someone driving it that it had an auto locker. Big heavy truck it's almost not noticable. I would occasionally get a clunk if I got on, off, and on the gas in a turn, but it is so worth it to have it always locked when accelerating. It unlocks while coasting. And you don't have to worry about "selecting" it and it's bulletproof and cheaper too.

 

Haha, this might happen sooner than I planned. My front axle is leaking so I need to open it up anyway and I've got a guy who will sell me a set of 37" Toyo Open Country MTs for about half of retail that look like they've only got a couple thousand miles on them.

Anybody interested in a set of Nitto Trail Grapplers 295/70/17LT? That's a 33x12x17 with about 5000 miles on them, maybe less as I've only had them for one oil change so far (every 3000 miles).

And just to confirm my initial question in my first post, all I need for a gear swap is the ring and pinion gears?