I have a 2000 EX V10 4x4 with 142K on her. I just paid the stealership almost $600 to replace the axle shaft seals on my right front axle and to diagnose a growl I would hear from my rear end after 25-30 minutes of continuous driving. It would just start like you flipped a switch on at 35mph and would continue on up to 70mph. I may have been too high pitched to hear above 70mph but still been making noise. Ford told me it was the ring and pinion making the noise and with the miles on the truck, to just drive it, it would not hurt anything. There was a leaking pinion seal that they said to do myself. They did recommend changing the fluid in the rear end for $170, and I said thank you, but no and took it to a service center next door to my work.

The new place took the rear diff cover off and found nasty muddy fluid in the rear end and the pinion had approx 1/4" front to back movement. He suspected someone blew an axle seal in the mud and didn't service the rear end. Looked like the mud had been in there a while. He said the bearings needed to be cleaned and he could probably save them for me instead of replacing them, which I agreed to. He used Mobil 1 75w140 synthetic gear oil. When he brought the "fixed" truck back, he said there is some kind of crush washer or spacer that he had to replace that you crush until the bearings "get a little tight", and that the bearings had "worn a pattern" and that I would hear a similar growling noise for "a few miles". Now, I hear the growling noise immediately at all speeds and it is the loudest at40-50mph but is there regardless of speed and is louder than it was before the service. This repair took place this past Thursday. Friday night on the way home from work, the O/D OFF light started to flash on the shifter and went away on its own after about 20 seconds. Last night (Saturday) on the way home from dinner (about 30 minutes from my house) the O/D light started flashing again and would go off on its own. It did this 2-3 times the last 5 minutes of the return trip. At the last 2 stoplights, when I would try to take off, the truck would miss and buck once or twice before going. Ran fine up to the actual stop, even with the O/D OFF light flashing. When I parked in my driveway last night, I put it in park and tapped the throttle and the truck died. It immediately restarted and will drive fine.

Any ideas? Are my two problems related? Is there a sensor in the rear diff that would cause the O/D OFF light to flash? And does his explanation of the noise make sense. It has been over 100 miles and the noise is still there, no quieter. Any help would be great! Thanks in advance!

Ryan

 

You do have an ABS sensor on the rear end......I think you will only fix this with a rear end rebuild or replacement........In my opinion it has been ran too long with the muddy fluid and play.......the gear set will wear in that way......once you move it back it will always sing. I'd check my local salvage yards for a donor and be done with it.

 

Thanks for the reply. Today, for the first time, the brake pedal would feel like it was "skipping" occassionally. Like a vibration in the pedal, but only once or twice, and seemed like the stopping power wasnt there. It was only from about 15 or 20 mph to stop, not from highway speeds. And then the SES light came on right as I pulled into my driveway. Could that be the ABS sensor? If so, could the shop that serviced my diff have "done something" to the sensor?

 

Possibly.....take a look at it.......it's on the front of the diff.......topside......in the middle

 

Thanks. What do I look for? If it is plugged in or anything in particular? Sorry for the NOOB questions, but I am not a car mechanic. Jet skis and guns I can do, but not trucks and drivelines... In your opinion, is it cheaper/easier to pay someone to rebuild the existing rear end or to buy a used assembly and swap it?

 

If you can do jet skis and guns.......you can do this.....this is easier .....no tiny parts to lose. I think a complete swap from a yard would be less expensive than a rebuild......you can swap the rear yourself........a rebuild requires some technical skill and experience....and in my opinion not a lot of shops can do it right.....even though they will try......you really need a shop that does a lot of them.....a well known off road 4x4 or performance shop is a better bet for this.
Get on the phone and do some pricing both ways though !

 

Thanks for the guidance.

 

The sensor was plugged in and looked the plug looked clean. I'll have to have the codes pulled from AutoZone or somewhere. Any guesstimates on a fair time to swap rear ends if I provide one to my shop? Is it a few hours or an all day project? For a "professional" mind you, not me. Is it something that a person can do without screwing somthing up? Any imperative or precise settings or calibrations? Or is it as simple as drop the old rear end out and bolt the new one in in it's place?

 

Just that simple........I don't know what a flat rate manual gives for time......but I think I could do it in my driveway and not take more than 4 to 6 hours.....although it is big and heavy......the key is to try to find a good low mileage one in the yard........no settings if you swap the whole thing .....I would re-torque the u bolts after 500 miles.....and have them pull the rear cover drain and replace the fluid.....will give your professional a chance to inspect it also....Do you know your gear ratio ?

 

I believe its a 3.73, but I'm not sure. It's a 2000 XLT 4WD V10. Were there optional rears? I really have no idea.

 

There were 3 codes for the front right wheel sensor and a code fore the vss on the rear diff? Anything to have the guy that serviced it check out?

 

They might have damaged your ABS(VSS) sensor on the rear

 

i bought my ex 2 yrs ago with 130k on the clock. the rearend made the whining growl sound. my dealer said it was common and most of them do it with this mileage. my fluid looked good but i changed it and a put the ls additive anyway. i now have 141k and the noise is no worse than when i bought it.

 

With that many miles it's recommended to replace the bearings, as bearings do wear. If they set the old bearings to new specs, they will often be noisy. Also, when using an old ring & pinion, it's very tough to get them quiet again because you'll have to get the depth & backlash identical as to what it came out.

Be careful when using salvage units. You never know what they've been through!

 

FWIW I just had my 240k rear end rebuilt in my truck. New differential, bearings, and ring and pinion and it was $1600.