2003 Ford Explorer rear end noise when deceleration

There is a tech bulletin about this and also rear hub bearings This is the rear end bulletin:
REAR AXLE NOISE REPAIR TECHNICAL SERVICE BULLETIN Reference Number(s): 05-23-3, Â Date of Issue: Â November 28, 2005 Superceded Bulletin(s): 05-12-6, Â Date of Issue: Â June 27, 2005 Related Ref Number(s): 05-12-6, 05-23-3, 05-6-18 ARTICLE BEGINNING DESCRIPTION REAR AXLE NOISE REPAIR ISSUE Some vehicles may exhibit an axle whine or hum during acceleration, deceleration and/or cruise. ACTION An axle repair kit has been developed which incorporates most parts required for a comprehensive axle repair. The kit should be used instead of installing a complete axle assembly to repair an axle whine/hum. Replace Ring and Pinion with Axle Kit and Components. FORD: 1997-2005 Expedition, F-150; 2002-2005 Explorer LINCOLN: 1998-2005 Navigator; 2003-2005 Aviator MERCURY: 2002-2005 Mountaineer NOTE: This article supersedes TSB 05-12-6 to update the Service Kit and Service Procedure information. NOTE: REFER TO THE "DIFFERENTIAL RING AND PINION" IN-VEHICLE REPAIR PROCEDURE IN THE ONLINE WORKSHOP MANUAL SECTION 205-00, FOR THE LATEST AXLE DIAGNOSIS AND REPAIR PROCEDURES. NOTE: FOR 1999 AND PRIOR MODEL YEAR VEHICLES, USE THE 2000 MODEL YEAR WORKSHOP MANUAL. NOTE: WHEN SERVICING THE REAR AXLE ON ANY 2002-2004 F-150, EXPEDITION, NAVIGATOR, EXPLORER OR MOUNTAINEER BUILT BEFORE 3/30/2004, IF FLUID REPLACEMENT IS REQUIRED, REPLACE THE ORIGINAL FUEL EFFICIENT HIGH PERFORMANCE (FEHP) SAE 75W-90 REAR AXLE LUBRICANT WITH SAE 75W-140 HIGH PERFORMANCE SYNTHETIC REAR AXLE LUBRICANT. WHEN THE FLUID TYPE IS CHANGED, REPLACE THE CURRENT "FEHP" METAL TAG WITH A NEW "75W-140" TAG (F3TZ-4121-AA). IN ADDITION, REMOVE OR BLOCK-OUT THE FEHP REFERENCE ON THE MULTI- Page 1 of 3
KIT ORDERING: REFER TO THE VEHICLE AXLE TAG FOR AXLE RATIO IDENTIFICATION à   5L3Z-4209-A = (8.8-Inch Ring Gear/3.31 ratio) (1997-2005 F-150) à   5L3Z-4209-B = (8.8-Inch Ring Gear/3.55 ratio) (1997-2005 F-150, 2002-2005 Explorer/Mountaineer/Aviator) à   5L3Z-4209-C = (8.8-Inch Ring Gear/3.73 ratio) (1997-2005 F-150, 2002-2005 Explorer/Mountaineer/Aviator, 2003-2004 Expedition/Navigator) à   5L3Z-4209-D = (9.75-Inch Ring Gear/3.31 ratio) (1997-2005 F-150, 2005 Expedition/Navigator, 1997-2002 Expedition/Navigator) à   5L3Z-4209-E = (9.75-Inch Ring Gear/3.55 ratio) (1997-2005 F-150, 1997-2002 Expedition/Navigator) à   5L3Z-4209-F = (9.75-Inch Ring Gear/3.73 ratio) (1997-2005 F-150, 1997-2005 Expedition/Navigator) THE AXLE SERVICE KITS INCLUDE THE FOLLOWING COMPONENTS: à   4630 - Head Bearing à   4628 - Head Bearing Cup à   4676 - Pinion Seal à   386989-S2 - Washer (Slinger) à   4621 - Tail Bearing à   4616 - Tail Bearing Cup à   4222 - Differential Bearing Cups à   4221 - Differential Bearings à   4209 - Gear Set (includes pinion shims, pinion nut and crush spacer) à   4209 - Instruction Sheet ORDER AS NEEDED: COLORED LABEL LOCATED ON THE RIGHT SIDE AXLE TUBE. IF THE AXLE IS A LIMITED-SLIP MODEL, USE XL3 ADDITIVE FRICTION MODIFIER IN THE QUANTITY RECOMMENDED BY THE WORKSHOP MANUAL. NOTE: 9.75 REAR AXLE HOUSINGS WERE REDESIGNED IN MID-1999, INCREASING FRONT PINION BEARING SIZE. REPLACING RING & PINIONS IN AN OLD-STYLE AXLE ASSEMBLY WILL REQUIRE INSTALLATION OF SPACER P/N YL3Z-4662-CA. SPACER IS TO BE INSTALLED BETWEEN INNER PINION BEARING AND COLLAPSIBLE SPACER. NOTE: THE KIT DOES NOT INCLUDE THE FOLLOWING ITEMS. SOME OR ALL OF THESE ITEMS WILL BE REQUIRED TO COMPLETE THE AXLE SERVICE, DEPENDING ON AXLE APPLICATION/STYLE. à   YL3Z-4662-CA - Pinion Bearing Spacer for 1997-1998 9.75 axles à   XG-14 - Gear Marking Compound à   4067 - Differential Shims 0.241" to 0.307" à   SAE XY-75W140-QL - High Performance Synthetic Rear Axle Lubricant à   XL-3 - Additive Friction Modifier (Limited Slip Axles Only) à   205-506 - Seal Protectors (Rotunda Tool) à   W710084-S439 - Wheel End Nuts à   390266-S100 - Differential Slave Pin Bolt (9.75" axles) à   387426-S100 - Differential Slave Pin Bolt (8.8" axles) à   4B422 - Axle Circlips à   ZC-21 - Metal Surface Cleaner à   TA-29 - Ultra Silicone Sealant à   TA-27 - Stud and Bearing Mount Retaining Compound and Sealer à   F3TZ-4121-AA - Fluid Tag (REQUIRED IF FLUID TYPE IS CHANGED FROM FEHP DURING REPAIR) WARRANTY INFORMATION WARRANTY STATUS: Eligible Under Provisions Of New Vehicle Limited Warranty Coverage. NOTE: REUSE OF RING GEAR BOLTS, CARRIER BEARING CAP BOLTS AND DIFFERENTIAL SLAVE PIN RETAINING BOLT REQUIRES CLEANING OF THREADS AND INSTALLATION OF TA-27 STUD AND BEARING MOUNT RETAINING COMPOUND & SEALANT.
4/24/2010 .
Growling noises can also be from the rear wheel hub bearings.

The wrong oil? Meaning not gear oil 85-90 wt.
If you mean they used engine oil then yes it could contribute to early part failure. I would say to put it on a lift, spin the rear wheels, any roughness in the hub bearing could be felt.

Should not have that much play. Were new parts used?
Crush spacer isn't working.