I own a 2010 ford f150 that make a grumbling sound when i turn. the dealeship has replased the clutches for the limited slip rear end 2 times now and it is happening again. they told me that the ford engineers are working on the problem but they do not have a fix for it yet. So they told me to just drive it with the positive traction engaged until they get a fix for it. not exactly the answer I was looking for. Anyone else having this problem

 

Positive traction?

 

It sounds like you have a electronic locking rear? Otherwise how could you control a limited slip rear? If that dealer does not come up with a better answer soon I would go to another dealer. They might have a better crew in the shop. I say that as I know of a now out of business Dodge dealer (BFO before Ford ownership) that told me I needed this and that to rid me of a problem I was having, not really thinking they were right I went to another and the problem was solved but it was totally different fix then the first dealer at a quarter of the price. My two cents, Chris

 

If you are not satisfied with the dealer's service, call Ford Customer Service.

 

I'm just guessing that this is the clutch plates chattering in a standard LSD.

Somewhat of a misnomer for the dealer to say ".... with the positive traction engaged" ... besides the name, a LSD is always engaged up to the point where the torque bias overcomes the internal clutches.

We had a 2010 at work that had a shutter in the rear and in the trans. IIRC the dealer installed new clutch plates in both to solve the problem. They were two distinct problems with two distinct symptoms.

Odd that replacing the clutches did not cure it. Some guys will just add a couple more bottles of ford's "friction modifier" and for the most part the problem will dissappear. Personally, i do not feel that is a proper fix for the problem. but that is just my humble opinion, and i have known some very good mechanics that will swear by it.

Perhaps the clutches just need a good "break in"? Anyone know how to break in a LSD?

 

I broke in the LSD of my old Explorer really good with some power braking action.

 

Find another dealer or call customer service. I would demand a new rear end or I would demand a written warranty on the existing rear end for 150K.

To the OP, welcome to FTE. You must keep this job ticket open so it doesn't lose it's warranty status when your truck does.

 

A phone call would be a waste of your time. Ford thought they had a fix and it turned out not so good. They are working on it and do not have a fix yet.

 

I had the same problem with mine, they fixed it and now it's starting to come back again.

 

guys, check the lemon laws in your state. If the dealer is passing the repair off until ford tells them what to do they are nothing but a parts changer and wil never fix the issue unless it bits them in the butt. If you have the right in your state, you can write a repair demand letter to ford to make them send an engineer to fix it. Just did that with mine and the truck is in the shop now till they finish replacing the belt drive on the motor that the dealer did not seem to know about. However, I got a 'it can't happen because they resealed it twice' for door leaks.
Remember, you can either chase the current dealer or use capitalism and go find one that wants to fix the issue.

 

My rear end just exploded going down the highway yesterday and ford won't cover because the previous owner built it as a saleen pickup and it has 23" wheels. Now i'm sitting here with a truck broke down and no way to get it going. I told them about all the issues with the rears and they didn't want to hear, basically told me sorry about your luck.

 

Just so I'm clear - you have 2010 with a supercharger and 23" wheels (tire size?), the rear end went out, and you want Ford to pay for the repair?

Never mind - I saw your other thread.

 

No fix for mine yet. Still under investigation!

 

Is this a problem with the LS rear ends only or is anyone having the same issues with the EL rear ends? Just curious...

 

I think it's just limited slip.