ccwbrd

And the the 2011 and up front 8.8 is a 31 spline just like the raptor. The 2009 and 10 maybe too, just do not have any experience with them. And the 2008 and older are 28 spline.

Logan24

So your telling me my truck is 2wd in 4x4...news to me. Lol

Howler

Yup. You're getting it.

Unless you pull the 4x4 **** out to engage the rear locker. Then you have 3 wheel drive up to 30mph when it disengages. Then you are back to 2wd, 1 in the front and 1 in the back.

LOL

montanaman

"So your telling me my truck is 2wd in 4x4...news to me. Lol "

That's essentially correct - without a LS or Locker in the back, all 4 wheels have the potential to provide push, but not at the same time. In 2WD you have one tire pushing in the back. When you kick in 4WD you have two wheels, one front, one rear, and if you've got an e-locker you've got 3 wheels pushing until it kicks out at 30 mph.


I'm hoping somebody chimes in who's already spent the thousand bucks putting a True-Trac or helical gear differential in the front, and can tell us how it went.

Al Kohalic

That's not exactly true. All 4 wheels will turn and have power in 4wd at the same time as long as one wheel does not lose traction. In the case that a wheel loses traction, the engines power will follow the path of least resist and send all the power to the wheel without traction. It is only in those instances that you only have 2 or 3 wheels turning in 4wd.


Logan, here is a good video explaining it from Jeep. It is essentially the same in our trucks. Jeep calls their one wheel spin control a BLD or Brake Lock Differential.


Thanks, that is good to know. I have been doing my own research since I have been debating on doing the same as Montana, and every website that I have been to shows the 8.8 as the same up to 2013.

papa tiger

Interesting side note, jack up one rear wheel with a floor jack on a inclined drive way and watch it head down the drive on its own.


I added LOL and it edited it out for some reason.

Howler

This was a joke by PT for sure, Please dont actually go try this.

ccwbrd

You have over 1200 post and you learn something new, thats not a bad thing. There are lots of people that do not know this.

F-250,LD

This is an excellent reason to use you parking brake. I have seen (multiple times) someone park, put the trans in park and watch the truck roll effortlessly down the hill. One (rear wheel) was on dry pavement, the other on ice. The one on ice spun backward allowing the one on the dry to spin properly. This is due to the open diff. The engine/transmission/driveshaft did not turn at all.

But I digress and and am off topic.

Remember that a LSD will apply power to both wheels IF both wheels are on the ground. If you are offroading the truck and float a wheel, that wheel will take all the power, the other will receive zero power. There must be resistance on both wheels to make the LSD work.

If you are looking for added traction on road, the LSD will apply about the same power to both wheels. Being the front wheels, both wheels will want to spin at the same rate. When making a turn, those wheels will want to spin at different rates. With the wheels trying to do both, the truck will want to push or understeer and go straight (this will only be noticed in 4wd).

Within the group that I offroad with, some have gone with an LSD in the front of their rigs (mostly 4runners and not F150s). The on road manners definitely change. Offroad, there is more binding and tire scrub. More understeer too. When floating a wheel, zero benefit of the LSD. These guys were more prone to CV breakage (same guys were breaking more CVs after the LSD was installed than before without).

Another issue with locking diffs (front, rear, true locker and to some degree and LSD), on off chamber slick roads/trails (locked) the vehicle will want to slide down hill. Again, experience with wheeling in the snow, I have walked right thru the same areas that a locked rig ended up in the low side ditch.

There is a reason that an open front diff is open and not locked.

If you are looking for increased traction while offroading, install a selectable locker. Be fore warned. Front lockers like to eat CVs.

mechanicboy

Thank you, some people aren't getting the mechanics and need visual representation. Explaining it with just words can create confusion and I get a funny look often when I try to explain it.

With an LSD you get Limited control. A tire in the air does not take 100% of the power and the one on the ground 0%, it if did the LSD is wore out and needs to be rebuilt/replaced. It sends some power, this is why your buddies with LSDs are more prone to CV breakage, like the guys with lockers.

Go on youtube and check it out.

The rest of what you said is correct.