We have a 5.4 3.55 4X4 automatic 4 speed that the rear end makes a looping grinding noise when you turn after a stop either left or right and vibrates on start up acceleration from rear end. Only happens on dry surfaces,gets worse with long highway miles but in 2 wheel drive and the truck loopes up and down like a tight turn in 4 whhel drive, Service dept has charged me $1064 to repair"supposedly" leaky rear axle seals, contaminated brake shoes, frozen ebrake cable, worn brake disc ,brake pads (front) after they did a brake job 12k before,when asked they said they turned rotors but did not change pads (now needs rotors), both lower front wheel ball joints( for Looping). I told them that wasn't it but they said thats what it needed, Drove it away same thing, took mechanic for ride to prove the noise, he added limited slip additive,said that would do it, when they changed the rear end fluid @ 94 k , now has 99k (all highway) with 100k warannty,it still makes grinding noise. Does anybody have any advice . thank you.

 

Same set up as me, with the same problems. It is definetly a problem in the LS clutches. You didn't specify that you have a LS rearend, but you probably do. I just had my pinion bearings replaced and made sure they put the LS additive in hoping it would cure the grabbing. It has done it since about 1000 miles and I figured the factory didn't put the additive in. It seems worse now, just having the truck back less than a month. My tire actually chirps when turning from a stop(low speed) and I drove a posi long enough to know what is going on. Not happy with the whole truck shuddering, but do like the idea of a locked rearend. Seems like many of the rearends from ford have serious flaws in them...

 

What size and gear ratio do you 2 guys have in your 4x4? I have a 4x2 w/ the 9.75 3.55 limited slip in mine and have not had any problems w/ it except the pinion seal leak. Got 23,000 miles on her.

 

If you have a 100K warrenty why did they cahrge you $1000? Anyways, i think you should just complain more. If you bring it in for a problem and they charge you to fix it, the truck should not leave the shop until it is perfect. Try talking to the manager or dealership owner, or the Ford area rep.

-Jon

 

Fisher, Did Dealer Tech. remove the ring gear carrier assembly and dis-assemble and inspect the internal clutches and/or axle and spider gears inside of the differential carrier?

Did You visually see any leaks (prior) on the rear axle assembly? If yes, I suspect that there is a problem inside the diff. carrier assembly. Such as, broken diff. nest assy. or broken or worn out clutch frictions or friction plates.

I would axle be tempted to remove the rear driveshaft, purchase a plastic dummy, slip yoke tube to install in rear of transfer case (which will prevent lube from flowing out of transfer case) and go for a very short LOW SPEED drive with rear driveshaft removed and transfer case locked into 4WD.

With rear driveshaft removed & vehicle in 4WD-- if the noise is still present, You may have a problem in the transfer case.

 

This is Fishers wife. He had to go to SC for a job and wont be back for ten days. I wrote down what you all said and brought it to ford when I picked up the truck. They said they emptied the fluid out of diff and put in new. They said they tightened the drums on brakes and for me to drive for weekend and see what happens. I only have 900 miles of warrenty left so I only drive it when I have to make our hill during a storm. Thank you for your help.

 

Mrs. Fisher

Pay real close attention to the truck to see if the repairs made a difference. I personally don't think it will. If this dealer cannot solve the problem with 900 miles left on the warrenty--I would seek out advise from Friends, Neighbors, Co-worker or someone on a reputable ford dealer and seek out this reputable dealer SOON--before the warranty runs out.

From what you and your husband have told us, I think this dealer does not have the experienced people to determine your trucks problem and solve the problem.

Many people do not know that some dealers do not have experienced people or willing people, that will work on drivetrain problems.

I used to do warranty driveline (differential repair) for an independant shop that a local GM dealer subleted all of drivetrain work to. Reason the dealership did this: they had no employess with enough experience to do satisfactory repairs or rebuild on differentials.

It was cheaper for GM to pay warranty one time (Me) vs. customer taking vehicle back to dealer three, four, five or more times. I solved all the problem vehicles that were given to me by this dealer.

I have a feeling that your vehicle problem can be easily solved, if the right person can lay hands on it.

If I can be of any more assistance; feel free to post.
gearmanx17

 

Get that truck to a different dealer. Your rear end needs to be fixed. Changing the fluid is not the answer. The limited slip clutches are bad and need changing.

 

Make absolutely sure your dealer has written a repair report on the problem, and get a copy for your own records. I had a situation 4 or 5 years ago with an engine knock just before my extended warranty was about to expire. My service manager told me not to worry, because as long as there is evidence of the problem before it expires, then the dealer is obligated to repair it to your satisfaction. I ended up getting a new engine 4,000 miles after my warranty was gone. Good luck.