shawj460

06 f150 fx4, 130000 miles, rear end fluid level is full, small amount of metal on the fill plug, anolg with sludge. fluid is clear...
OK so im currently on leave 1300 miles from home, and while being away i noticed a loud whining coming from the rear end. it gets louder as i accelerate and it kinda disipates at around 60 mph, could be the drowning of the road noise or tires, but anyway its kinda loud and abnoxious. from inside the truck i couldnt pinpoint, so i put it on jacks and had my uncle run the truck in drive. being off the ground with no load it really whined, not a hum a loud high pitch whine. i took a needle stethlascope and listened to the pig, and then i went from the center out towards the tiresm it got quieter, and on the front side by the pinion it was quiet. once it was on the diff cover on the rear it was loud and noticable. Now in reverse it doesnt make any noise. so my ultimate question is what could it be, my guess carrier bearings and what can i do to make it last since im 1300 miles from home and i need to get back by monday otherwise im awol. anyhelp is great help!!!

imp

You've done everything right. Your findings say NOT pinion bearing noise (pinion bearings DO whine, because of the high speed, when one goes bad), NOT axle bearing noise, out at wheel ends of axles. This leaves differential side bearings, or gear tooth noise, or both.

A failed side bearing, depending on which side, can allow the gear teeth to either mesh CLOSER together or FARTHER apart. This will produce gear noise, but, generally, the noise will not go away when the vehicle coasts at cruise speed with closed throttle. As I understand your description, the noise is worst when the gears are working hard, accelerating or keeping the truck at speed, noise diminishing or gone when coasting. Finding metal particles was a likely tip-off to gear tooth noise.

I would remove the center section cover plate, scoop out ALL the remaining oil with your fingers and rags, looking carefully for metal particles or chips. The bigger the chips, the bigger the potential trouble. Wipe clean some ring gear teeth in succession, look closely at the tooth surfaces. Unless they are shiny and mirror-like in appearance, they are damaged. Look for pitting, chipping, scoring, and discoloration from heat. Unless good-sized chips of metal are chunked out, it is possible the gears may get you through a couple thousand more miles. Put in some HEAVY gear lube, GL-2, 3, or higher, in at least 140 weight. That will cushion those damaged teeth. If you go this route, drive it lightly, be aware of sudden sharp increase in noise level, as that might mean teeth are about to fail.

Keep in mind that only one fairly large chunk of metal, say, the size of a large green pea, can initiate destruction of the whole ring gear, whereby the first broken off tooth jams the next, and they strip off like kernels of corn off a cob. If you opt to take the chance on it, do let us know how you make out. Good Luck! imp

shawj460

thank you IMP, i took a chance on it and i threw some lucas, in the diff. i made it home, was a long 21 hr drive but im here. im taking the cover off today to inspect it, im a engine builder, never really rebuilt a rear end, what would make this an easier project. id love to just rebuild it myself. i was reading up on some of the diffs, for this year and i find that the limited slip is a clutch pack. so that worries me, also how hard is it to set the preload. and if i do a rebuild would i have to change the pinion and ring. or only if they are worn out ( pitted, chipped etc). or would it just be easier to take it to someone? and would u know of an estimate price range?
Thanks again your knowledge is greatly appreciated

shawj460

ok so i pulled the rear diff cover off, and drained out all the oil. it smelt a lil burnt but the oil was newish, looked really clear, almost synthetic. but anyway i noticed there was no gasket on the cover just a heavy layer of gasket maker/sealant. so makes me wonder who was in the truck before. anyway the ring and pinion look ok. has the normal wear marks on the gears, (shiny ness and it is only shiny within the teeth. BUT..... i seen that the spider gears arent looking so hot. had a chip in one, a dull edge in another and looks like rust but assuming pitting on the teeth. wasnt real happy but isnt there an easier way to rid the clutch pack spider gears, and put in like a spoool or tru lok. without the hassle of the ring and pinion. never done a rear end but im very mechanical savy. would like to fix this myself and change the limited slip im the process. Two birds one combo wrench. any inputs would be great i will upload some pics as soon as i can. Thanks

0hsiks_crewcab

Easy to do, tools needed torque wrench, breaker bar, dial indicator, lithium grease something to put in between the ring teeth to establish gear pattern. I'm not 100% about the preload I'm having difficulties remembering how to do that I have to look back at the FORD technical training website for that. Backlash is adjusted with appropriate shims. I'll try and do a copy and paste on it tomorrow on the tolerances and etc... Also I would just replace the ring and piñon, if there was any metal shaving its possible they embed themselves in the ring and piñon. Plus goo opertunity to upgrade anyways.

shawj460

Ok after careful consideration i have considered taking out the LS setup and putting in a tru lok setup. but i think my whining noise is coming from the carrier bearings. dont think the noise could be from the spider gears if its constant even when not turning., any good ideas on nice locking systems?

0hsiks_crewcab

Removal

1. Remove the axle shafts. For additional information, refer to Axle Shaft in this section.

1. NOTE: Index-mark the position of the differential bearing caps, as arrows may not be visible. The differential bearing caps must be installed in their original locations and positions.
   Remove the 4 differential bearing cap bolts and the 2 differential bearing caps.

1. NOTICE: Place a wood block between the pry bar and the axle housing to protect the machined surface from damage.
   NOTE: Index-mark the position of the differential bearing shims. The differential bearing shims must be installed in their original locations and positions.
   Using pry bars and wood blocks, remove the differential carrier assembly from the axle housing.

Installation

1. Position the differential assembly in the axle housing.

1. Install the originally removed differential bearing shim on the LH side.

1. NOTE: Apply pressure toward the LH side to make sure the LH differential bearing cap is seated.
   Install the LH differential bearing cap and loosely install the 2 differential bearing cap bolts.

1. Install the original differential bearing shim on the RH side.

1. Using the Shim Driver, fully seat the differential bearing shims.

1. Install the RH side differential bearing cap and tighten the 4 LH side and RH side differential bearing cap bolts.
   • Tighten to 112 Nm (83 lb-ft).

1. Rotate the differential assembly to make sure it rotates freely.

1. Measure the ring and pinion backlash.

1. Install the axle shafts. For additional information, refer to Axle Shaft in this section.

Backlash between ring gear teeth and pinion teeth0.203-0.304 mm (0.008-0.012 in)
Pinion bearing rotational preload1.5-3.0 Nm (13-26 lb-in)

0hsiks_crewcab

Heres a better on since its for the lsd.

1. Remove the differential carrier. Tag the differential shims and bearing cups for location. For additional information, refer to Differential Carrier in this section.

1. Remove and discard the 10 differential ring gear bolts.

1. NOTE: Care should be taken not to damage the differential ring gear bolt hole threads.
   Insert a punch in the differential ring gear bolt holes and drive the differential ring gear off.

1. If checking differential case flange runout, install the bearing cups in their original location and install the differential assembly.
   1. Install the bearing caps and differential shims.
      • Rotate the differential assembly to verify the bearings have seated.
   1. Install the Dial Indicator With Bracketry and record the differential case runout.

Final disassembly

1. NOTE: The anti-lock ring cannot be reused once removed.
   If necessary, remove the anti-lock ring.

1. Using the Differential Bearing Remover and Step Plate, remove the differential bearings.

1. Remove the differential pinion shaft lock bolt and remove the differential pinion shaft.

1. Remove the differential clutch spring.

1. Remove the differential gears.
   1. Remove the 2 differential pinion gears.
   1. Remove the 2 differential side gears.
   1. Remove the 2 differential pinion thrust washers.

1. NOTE: Keep the differential clutch packs in order. Do not mix the differential clutch packs. The differential clutch packs must be reassembled in the same sequence.
   Remove the differential clutch packs and differential side gears and tag them RH and LH with the selective shim.
   • Clean and inspect the remaining components of the differential case for wear or damage and install new components as necessary.

1. NOTE: Do not use acids or solvents when cleaning the differential clutch pack. Wipe components with a clean, lint-free cloth only.
   Clean and inspect the differential clutch packs for wear or damage and install new components as necessary.

Assembly

1. NOTE: Use 118 ml (4 oz) of the specified friction modifier in the axle.
   Pre-lubricate each steel clutch plate and soak all friction plates with friction modifier for at least 15 minutes.

i have a little more to this one but it has more than 10 pictures so it wouldnt let me post all of it at once.

0hsiks_crewcab

1. NOTE: Do not mix the differential clutch packs or selective shims from one side with the other.
   Assemble the differential clutch packs (without the selective shims) on the respective differential side gears.

1. NOTE: Make sure the correct mandrel is used with the Differential Clutch Gauge.
   Place the base portion of the Differential Clutch Gauge in a vise. Install the differential clutch pack and differential side gear (without the selective shim) on the gauge.

1. Position the Differential Clutch Gauge (15-101) hand-tight on top of the differential clutch pack.

1. Install the Differential Clutch Gauge (15-101) over the disc and differential clutch pack.

1. Install the nut of the gauge over the top and base stud.
   • Tighten to 6.7 Nm (60 lb-in).

1. NOTE: Selective shims shown are available as part of the Clutch Pack Replacement Kit F5AZ-4947-BA.
   Use the feeler gauge and select the thickest blade that will enter between the tool and the differential clutch pack. The reading will be the thickness of the new selective shim.
   
   Selective Shims
   
   Part NumberDescriptionE0AZ-4A324-G0.025 inE0AZ-4A324-H0.030 inE0AZ-4A324-C0.035 inE0AZ-4A324-D0.040 inE0AZ-4A324-F0.045 in

1. Remove the Differential Clutch Gauge from the clutch pack and differential side gear assembly.

1. Install selective shims on the clutch pack and differential side gear assembly.

1. Install the differential side gear in the differential case.

1. Install the differential pinion gears with differential pinion gear thrust washers in the differential case.

1. Using a soft-faced hammer, install the differential clutch spring.

1. NOTE: If a new pinion shaft lock bolt is unavailable, coat the threads with threadlock prior to installation.
   Install the differential pinion shaft and install a new differential pinion shaft lock bolt finger-tight.

there is still a little bit more.

0hsiks_crewcab

1. Check the torque required to rotate one differential side gear.
   • Mount the differential assembly and Differential Clutch Gauge in a vise.
   • The initial minimum break-away torque, if original clutch plates are used, must be within specification. The minimum rotating torque required to keep the differential side gear turning with new clutch plates may vary.

1. Using the Differential Side Bearing Installer, install the 2 differential bearings on the differential case.

1. Position the differential ring gear, the new anti-lock speed sensor ring and the differential case. Align the bolt holes by starting 2 new bolts through the holes in the differential case and into the differential ring gear.

1. Install the 8 remaining new differential ring gear bolts.
   • Tighten to 105 Nm (77 lb-ft).

1. Install the differential carrier. For additional information, refer to Differential Carrier in this section.

Sorry for the 3 different posts we are limited to 10 photos so yeah. i just copied and pasted from the Ford PTS website. good luck man im sure this should be more than enough info. Oh as for the locker auburn makes a pretty good one for the mustang and its still an 8.8