2 Questions:

The Lariat I am most likely ordering only comes in the 3.55 Elocker rear end. What are the advantages and disadvantages of the E-locker? Is basically like having all wheel drive only in the rear end?

Also, do 18" Wheels have a smoother ride than 20" wheels? And can you tow more with 18 inch wheels? I ask because 17" wheels with 7 lugs comes with the max tow package.

I haven't ordered yet but I going to be really soon. Trying to collect as much info as possible.

Thanks

 

For the F150s, there are three types of rear ends:
Open rear - power will be routed to the wheel that turns the easiest. Get one wheel in the mud, and you're stuck.
Limited slip - the differential has clutch packs that will transfer some of the power to the non-spinning wheel. LS is better than nothing, but has a few issues. Sometimes you may need to apply a bit of brake to get the clutches to engage. Also, fluid changes require a friction modifier - too much and the LS will never engage, too little and it will engage too often ("chattering" in hard turns) and will eventually wear the clutch packs out.
Electronic locker - the rear end operates as a standard "open" rear end normally, but you can engage the locker and lock both wheels together. When locked, the wheels will turn at the same rate, regardless of their current traction situation. The E-locker must be engaged by the driver - it is not automatic.

To me, the e-locker is better than LS or an open diff if you are going with a 2WD truck. At least you have a bit more options for getting out of a sticky situation...

 

Is Ford offering a locker on 2WD F-150's for 2012? When I got my 2011 FX4 the only trucks that could get the E-lockers were 4X4's with 3.73's if I recall correctly.

But maybe I was mistaken.

 

Just wondering why are you getting 3.55's? Is it the EcoBoost?

 

For 2012 Elockers are now available in most axles ratios, except when ordering the HD package which requires the 3.73 LS axle. The LS is now ONLY offered in that 3.73 HD axle with the 17" 7 lug rims. And those 7 lug rims, OP, have the highest capacity. But I don't think there is much capacity difference between the standard 17",18", or 20" rims (all of which are lower than the HD 17").
18" wheels usually have a more cushioned ride than 20's because of the taller sidewalls of the tires. 20's are better for handling with less roll on curves, etc. The factory offerings of wheel/tire combos all end up being within approximately 1/2" of each other as far as total height or diameter. Some of the smaller wheels actually provide larger overall diameter than some of the 20's.

 

That and 20's on a truck...skeptical. I can't believe they offer them on the FX4.

 

As brakes get larger, wheel sizes will get larger to properly clear the calipers and cool the brakes. It wouldn't surprise me if, eventually, 17" wheels are no longer even offered on half-tons; as manufacturers are going to look towards larger brakes for better brake feel, less fade, and decreased stopping distances.

If you've ever taken the front wheel off a new F150, you'll notice that the disk and caliper alone is larger than what used to pass for a wheel on many half-ton trucks (15").

 

I don't know. With the decrease in weight they are planning they shouldn't need to increase the brake size.

 

That might be the case, but it also might not be. It all depends on what kind of performance goals they expect to meet. All it takes is one manufacturer deciding to drop weight AND increase rotor size, than it's only a matter of time before they all do it.

Speaking of brakes, I'm actually amazed that an F250/F350 (13.66") has smaller front brake disks than an F150 (13.8"). You have to step up to an F450 (14.53") to get larger brakes.

Considering the new Silverado HD has 14" rotors, I'm thinking a brake size increase is coming for the Super Duty. It wouldn't surprise me if the F250/F350 gets the F450's huge 14.53" front brakes.

 

"Just wondering why are you getting 3.55's? Is it the EcoBoost?"

Yes, I am getting an ecoboost. I am moving from a 2002 f250 with the V10.

Thanks for the info guys. It looks like the e-locker is the way to go.
Is there a way to copy the summary of the build on the ford site and paste here? That way I can show you guys what I am thinking.