Hello guys,

I am going to make a beach run with some friends within the next couple weeks or so and I want to make sure I have my facts right.

I am new in the 4X4 world as well as the F150 world. I just have a couple questions about my 2010 Screw FX4.

I know how to engage the 4X4 and locker but I am unsure when the locker disengages. I am confused when i read the manual. I believe it says that in
4X4 low the locker will shut off in speeds higher than 45-55 mph. In 4hi it will shut off above 20-30mph. These numbers are estimates because I don't remember exactly what the manual says. I know that the numbers are higher in 4low. My question is why??? I thought in 4low you are not supposed to go that fast.

My other question is if anybody knows if it's true that if you have a locker you can't have LS? I know that my truck has traction control (TCS). It seems weird that a truck with an offroad package would not have LS. I have not had a chance to jack up my truck and check the wheel spin to verify what I have. Also when on the beach I will probably want to shut off the TCS. When shifting from 4x4 to 2wd and back do I have to shut off the TCS everytime?

Thanks guys and I would appreciate any advice since I am obviously a little ignorant to off roading in f150's

 

if you have a locker you have no need for a ls diff do some research on the two different types of differentials

 

Well it would be nice to have LS when the locker is not engaged. Apparently the FX4 has a open axle when the locker is not being used. I was just wondering if it was possible to have an axle with both LS and a locker. Several people have told me that it does not exist.

 

yeah no such thing listen to the several people

 

If you are going on the beach in sand, be careful you don't overheat the transmission.

With my 02 that has the tow package and a large trans cooler, the transmission will get hot if I aggressive at all on the sand. I start smelling the fluid.

 

The Auburn ECTED electric locker has mild limited slip capability when unlocked, as did the late, great Detroit Electrac (discontinued in '07, I think). I don't think the ECTED has a Ford 9.75 application but you can check. They just reengineered it and offered a few new applications. For the most part, though, you will have to pick your poison. Me, I would buy a Detroit TrueTrac. Pretty effective but with very goo manners and it basically is a lifetime unit... unlike most clutch LSDs that wear out and get ineffective over time.