I was turning around and had to go through a very shallow ditch, when I did the truck suspension flexed a little and the passenger side rear tire began to spin free. The truck stopped and the right rear kept spinning and the rear drivers side never even tried to engage. Luckily, I flipped her into 4HI and pulled out. Obviously, there's something not right. Anyone else have this or any suggestions?

 

Discussed...

https://www.f150online.com/forums/sh...t=Limited+Slip

https://www.f150online.com/forums/sh...t=Limited+Slip

 

Ford's LS is that weak huh...ouch. My buddy's Jeep has factory LS in the rear and it's damn near impossible to slip and we've pushed it.

 

Not all 4x4's come with limited slip,from what Garo described, it sounds like he doesn't have one

 

I figured because he title it "Limited Slip" he had it, you're probably right. I have an open diff. on my 02 and boy does it show.

 

I would check your factory sticker and see if they added the $300 for a limited slip rear.

 

OK, maybe I'm confused here (entirely possible, I'm sure someone will show me the light, no need to do it with flames). If one wheel is spinning but the other is not, doesn't that mean the LS is working correctly? Doesn't one wheel have to spin free before the LS action can kick in? LS shifts power but it doens't put a break on a free spinning wheel and transfer 100% power to the non-spinning wheel.

Or is the complaint that the wheel that power is being shifted to isn't getting enough power shifted to it? I'm not sure how you would know that without some fancy machinery to load test. The fact that you need 4HI vs. 2HI in a given situation has to do with lots of stuff besides the LS. The power of your engine, the gearing in your diff, the traction environment, the weight of the vehicle, the "angle of attack," etc. Right?

And isn't this desireable to an extent. Lets say you're in 2HI, climbing a trail, and your rear passenger wheel starts to spin free in some loose gravel. Your power should be shifted to the rear drivers wheel up to the point that it's about to spin too. If so much power is shifted that it's allowed to spin also (or instead), you're going to dig yourself into a nice little hole that you can't get out of without a winch and a tree or a buddy and a tow strap. So you hit the gas, passenger wheel spins some but the driver's side does not, are unable to climb further, but at least both wheels aren't spinning, so you kick over to 4HI briefly and get some pulling action in the front axle and off you go. You don't swear at your truck because it didn't shift enough power to one wheel in this particular situation, you thank it for not digging you down to your axle before you have time to react. Right?

And I'm guessing that a factory LS is like anything else; it's tuned for "most" situations but not extreme cases. If you're one of those "technical" 4WD guys and you know you're regularly going to be putting one or two wheels in the air because you're climbing bolders or whatever, then yes, you do want 100% of your power to be shifted and you go with an expensive locker system. If you stay with factory, as others have suggested, you can do little things like apply e-brake pressure to temporarily change the behavior. But then again, if you have 4WD, why you would do this instead of kick over to 4HI would be a bit of a mystery to me...

 

well, for one, i simply hate using the 4x4 untill i absolutely have to, i shouldnt have to put her in 4hi to cross a little ditch, that is bs ford, dont get me wrong, i am a di hard ford guy now, and im not bashing ford, but come on guys, you paid an extra what 400 for a ls that works pretty much like an open diff?? for me, my ls will leave two lines if i punch it on flat ground, but the moment i flex the suspension, im screwed, guess i will have to talk to the ford tech and tell them to put less LS modifier in there so it will lock up quicker, hopefully 4oz will work instead of the usual 6

 

Same here. This just seems like one of those situations, though.

That's exactly what it's supposed to do. Your LS is essentially open until one wheel spins free. All things being equal, both wheels should be getting equal power. That is to say, that if you punch it on a flat surface where the traction is the same under both wheels, there will be no LS action and both will turn (or spin and leave tracks if you're really getting into the throttle) equally. It's when you flex the suspension that the traction conditions change between the two sides and the LS action can kick in.

Limited slip isn't no slip. It's limited. One wheel has to spin faster than the other for LS to know it's needed, kick in temporarily, and limit slip. Only under those conditions will there be any LS action in your diff.

 

So what exactly do you have to do to get the LS to kick in?????

 

If your LS is in the rear, a trick to engage the ls would be your parking brake. Your e-brake will allow you to equal the amount of torque on each wheel so they both spin. If you have LS in the front the standard brake will help engage/torque the LS up there. Go try it for yourself.

 

Josiah is right on.

I tried it and it works. I learned it from jeep community when i had my old jeep in past stock bone w/ limit slip then now turned into rock crawling


Later
YOMAN!

 

A few weekends ago I actually took my truck mudding with a bunch of buddies. Lone behold I got stuck twice in some really deep swampy stuff and I tried to get out. I noticed all 4 tires were dug in the ground. That means my limited slip on both front and rear were engaging trying to get out. Otherwise it would have been just the front left and back right tire trying to get out if they were open rears. LS is standard on the FX4's. The factory Goodyear ATS tires on this thing SUCK! Do not take your truck off road with these tires cause they can't dig out of mud worth a crap.

 

Fords limited slip sucks. Its supposed to transfer power to the wheel with traction, but it doesnt (no big surprise). Like they said apply the parking brake a little or your regular brakes. This helps trick the diff into sending a little more power to the wheel with traction.

 

d0n_3d, you don't have LS in the front, only in the rear. It works ok but it depends on how much street use your truck has been through...clutchpacks wear out over time. You can't expect much from a clutchpack driven LS even if it is from Ford, swap to an aftermarket gear driven if you're looking for a performance LS. The reason your tires dug is possibly due to weight transferring to each tire and they take turns slipping and gripping. On my video you'll see both tires in front spinning but whats actually happening is one tire will slip and the other will drive, interchanging very quickly. It's mostly in the scene where I'm coming at the camera up the hill.