bambo2888

Symptoms:

Under power (pulling out of a parking lot), making low speed maneuvers
Wheels have to be turned left or right (at least 30-40%)
Will not replicate if wheels are aimed straight
No noises, grinding, or squealing

If all of these criteria are met, I get a relatively heavy vibration. Like I said, it will not do it when the wheels are aimed straight and will no do it if throttle isn't applied.

Any ideas? I have done research on the IWE, the hubs, the actuators, etc, but I do not have any grinding or loud noises.

Thanks!

ray h

Sounds alot like your limited slip clutches are grabbing.
Have you recently had the rearend fluid changed and perhaps they didnt put any friction modifier back in.
Or are you sure its coming from the frontend.

thump

Where do you feel the vibration the most (e.g. through the steering wheel)?

May be an obvious question.. but are you sure that 4WD isn't engaged?

bambo2888

i feel it through both the steering wheel and the gas pedal. 4wd is not enagaged.

is there anything that i can do about the LS? replaced fluids, etc?

thump

I'd agree with Ray H then:

TSB 06-4-4
LIMITED SLIP AXLE CHATTER, SHUDDER, BINDING SENSATION, OR VIBRATION DURING LOW SPEED TURNING MANEUVERS
FORD:
2002-2004 Mustang, Explorer
2003-2004 Expedition
2004 F-150
LINCOLN:
2003 Navigator
MERCURY:
2002-2004 Mountaineer


This article supersedes TSB 06-02-16 to update the Service Procedure.

ISSUE:
Some 2003-2004 Expedition, 2003 Navigator, 2004 F-150 vehicles equipped with a 9.75" or 8.8" limited slip rear axle, and 2002-2004 Explorer 4dr, Mountaineer, and Mustang vehicles equipped with 8.8" limited slip rear axle, may exhibit a chatter, shudder, a binding sensation, or a vibration during low speed turns. On 4X4 vehicles, the sensation may appear to be originating from the front axle or the steering gear.

ACTION:
First verify the condition. On 4X4 trucks ensure that the vehicle is in 2WD, to isolate the rear axle. On all vehicles, turn the wheel fully right (or fully left) and then accelerate the vehicle. If the condition is verified to be in the rear axle, replace the limited slip clutch pack.

SERVICE PROCEDURE

CAUTION:INSTRUCT THE CUSTOMER NOT TO TOW WITH THE VEHICLE FOR 500 MILES (805 KM) AFTER THIS REPAIR, TO ALLOW THE AXLE TO BREAK-IN PROPERLY.

Order and install the appropriate clutch pack, follow the instructions detailed in the Workshop Manual.

• 6L1Z-4947-A (9.75" limited slip)
• F5AZ-4947-BA (8.8" limited slip)

NOTE:INSTALLING A CLUTCH PACK INTO AN INDEPENDENT REAR SUSPENSION (IRS) AXLE IS DIFFERENT FROM INSTALLING A CLUTCH PACK INTO A SOLID-BEAM AXLE. BE SURE TO FOLLOW THE APPROPRIATE WORKSHOP MANUAL PROCEDURE.
INSTALLATION TIPS

• Be sure to install NEW circlips and halfshaft/wheel end nuts on IRS rear axle (not included in the service kit)
• Soak the new clutch packs in Additive Friction Modifier (XL-3) for fifteen (15) minutes prior to installation
• For IRS axles, the half shaft seals need to be replaced. Expedition and Explorer/Mountaineer applications should use seal kit part number 5L1Z-4A109-A. Removal of the half shaft excluder seal 1L2Z-1N013 may be required, if equipped, to facilitate re-assembly
• Refill axles with 4 oz. Additive Friction Modifier (XL-3) and the necessary amount of Rear Axle Lubricant (XY-75W140-QL), regardless of the axle lubricant system originally used in the axle. Fill to capacity recommended in the Workshop Manual

NOTE:AXLE FLUID REQUIREMENTS HAVE BEEN CHANGED. ALL VEHICLES BEING REPAIRED BY THIS TSB MUST HAVE REAR AXLE LUBE XY-75W140-QL INSTALLED, IN PLACE OF XY- 75W90-QFEHP. AS PART OF THIS REPAIR, CHECK AND REPLACE IF NECESSARY THE CURRENT XY-75W90-Q"FEHP" METAL TAG, WITH A NEW 75W140 TAG (F3TZ-4121-AA). ADDITIONALLY, REMOVE THE MULTI-COLORED LABEL WHICH IS LOCATED ON THE RIGHT SIDE AXLE TUBE, OR BLOCK OUT ANY/ALL "FEHP" OR "75W90" REFERENCES ON THE LABEL.

PART NUMBERPART NAME6L1Z-4947-A9.75" Axle Clutch KitF5AZ-4947-BA8.8" Axle Clutch Kit5L1Z-4A109-AAxle SealXY-75W140-QLRear Axle LubricantXL-3Additive Friction ModifierW710084-S439Nut (Wheel End)2L1Z-4B422-CACirclips (for 9.75")1L2Z-4B422-BACirclips (for 8.8")F3TZ-4121-AAMetal Tag - 75W140
WARRANTY STATUS:

Eligible Under Provisions Of New Vehicle Limited Warranty Coverage

cole_ford

Had the same problem when I bought my truck. Dealership told me if it gets bad enough, replace clutches in LS. I changed rearend fluid and added friction mod. Vibration went away

bambo2888

Thank you THUMP and COLE, VERY much. All very good info. You saved me a lot of time and hassle and probably $$ too.

So consensus is to just ignore it? If you guys think it may help, maybe I'll service the diff and add the friction modifier and check for improvement? Would it be necessary to change the clutch packs out?

Thank you guys again, so much.

plucroy

Mine did the exact same thing last year. Had the fluid changed and add 2 bottle of friction modifier instead of one. Everythings good now !
Hope it helps.

ricrok

You shouldn't have to change out the clutch packs. And if the diff was recently serviced just add friction modifier and you should be good.

geraldmac2

I just changed my rear gear fluid and still have the vibration. heres what i used,

valvaline 75w-140, and 7 oz.tube of trans-x posi-trac limited slip gear oil additive.

should i have used somthing else?