I kept reading posts from forum members reporting bad differentials and replacements. From the threads, it seems that there are a couple of common symptoms of bad differentials (or differentials about to go bad):
1.) Differential leak (doesn't happen to everyone).
2.) Bogged performance (doesn't happen to everyone).
3.) Clunk / Clank.
4.) Card in spokes sound (clak, clak, clak when backing up / coming to stop).
Am I missing anything here?
Anything in the list that shouldn't be there?
We have to adequately document the symptoms so that people are not taking in their cars blindly. I noticed that dealership mechanics tend to BS more with people who do not know the exact problem with their cars.
BTW... many members also reported that they never had leaks or smells or sounds but they got their diffs replaced anyway by dealers who spotted a bad one. What criteria do dealers use to detect a bad differential?
4.) Card in spokes sound (clak, clak, clak when backing up / coming to stop).
Oh crap! I think I just heard that today... when I was backing out of the driveway i heard this weird grinding (or so I thought) but now that you say clakking that may be more accurate. I thought I was dragging an empty soda can but the noise then stopped. It was loud enough to make me put on the brakes.
When I backed my car, I have my clutch pedal pushed in and shifter in reverse. I let my car roll down the slope since I don't want zoom onto the road in reverse. That is when I hear that sound too. I haven't taken my car in to the dealership, will do that next time I get an oil change (real soon).
Even better questions, for people with bad diffs:
1.) What are your driving habits?
2.) Where you park your car, is it sloped?
3.) How many miles do you drive before it goes bad?
Basically, I am trying to establish a "pattern", engineering deduction here. Everything is reproducible given the right conditions and with the diff being a mechanical part, the basic reasons for it going bad must be in essence the same.
When I backed my car, I have my clutch pedal pushed in and shifter in reverse. I let my car roll down the slope since I don't want zoom onto the road in reverse. That is when I hear that sound too. I haven't taken my car in to the dealership, will do that next time I get an oil change (real soon).
Even better questions, for people with bad diffs:
1.) What are your driving habits?
2.) Where you park your car, is it sloped?
3.) How many miles do you drive before it goes bad?
Basically, I am trying to establish a "pattern", engineering deduction here. Everything is reproducible given the right conditions and with the diff being a mechanical part, the basic reasons for it going bad must be in essence the same.
1) Guaranteedly one of the most aggressive drivers on the forum
2) Never parked the car on a slope
3) Had leak fixed at 4,000 mi and having diff replaced at 24,000
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2003 Dodge Ram 4x4 QC/SB - w/ a 4-horse Bison trailer in tow
1) Guaranteedly one of the most aggressive drivers on the forum
2) Never parked the car on a slope
3) Had leak fixed at 4,000 mi and having diff replaced at 24,000
You aren't aggressive! You are mysterious
I have a whine I just had my car in Monday and they replaced the pinion seal (again). Wouldn't they have noticed the diff was bad or would I have to tell them about the whine. It isn't really loud but you hear it when you are winding through the gears???
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11/08/06 Sly GXP is here!!!!!! I am Sol-Happy!
11/21/05 Aggressive SOL arrives....(11/09/06 sold)
I've got what I think is the clunk. Not entirely sure, but whenever I let off the gas quickly at lower speeds, it seems to clunk. Initially I though it was the transmission, but then I listened for it, and it's coming from the rear.
I woke up this morning and noticed a puddle under the diff. took it to the dealer and over the phone they said they need to replace the (and it sounded like) Steel. Does anyone know what they may have said? I was to busy at work to question them.
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08' Sly GXP - JPMcoachworks Automatic Trans. Shifter, Custom Center Console and Seat Belt Loop , K&N Filter, Stuby Antenna, Lil Chromies, Kappashield, Etched Glass Decal, MBRP Stainless Steel Heatshield, ASAP Airbag light cover, Slotted Side Marker, Reverse Light Covers, Rear Stop Light and Autobot Decals, Bi-Xenon Headlights and Foglights - Picked Up 08/01/2008
I woke up this morning and noticed a puddle under the diff. took it to the dealer and over the phone they said they need to replace the (and it sounded like) Steel. Does anyone know what they may have said? I was to busy at work to question them.
Pinion Seal
Marie!! Call the dealer...they probably have to replace your rear differential carrier. Same thing they're doing with mine.
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2003 Dodge Ram 4x4 QC/SB - w/ a 4-horse Bison trailer in tow
I woke up this morning and noticed a puddle under the diff. took it to the dealer and over the phone they said they need to replace the (and it sounded like) Steel. Does anyone know what they may have said? I was to busy at work to question them.
Steel? Oh . . . seal. Pinion Seal. Common problem.
Took my '06 in at about 4K with a whine that drove me nuts at about 35 and again at 55-65 mph. Driving in town 90% of the time the whine was a constant. I had the service manager drive it and got the the standard answer... sitting closer to the rearend, you would hear more noise. He did agreed that the whine was there but referenced the GM memo that advised us that it was "normal". At 8K I took it back in. Played nice and took another drive and the service manager. He agreed that it was more pronounced than before and annoying as hell in freeway traffic . They installed a new L/S diff. the next day and the service ticket noted "ring & pinion gears failed causing whine". Sadly I have much the same whine as before but it's at a much lower decibel level... for now. I don't know if this helps you much... but you have lots of company.
Took my '06 in at about 4K with a whine that drove me nuts at about 35 and again at 55-65 mph. Driving in town 90% of the time the whine was a constant. I had the service manager drive it and got the the standard answer... sitting closer to the rearend, you would hear more noise. He did agreed that the whine was there but referenced the GM memo that advised us that it was "normal". At 8K I took it back in. Played nice and took another drive and the service manager. He agreed that it was more pronounced than before and annoying as hell in freeway traffic . They installed a new L/S diff. the next day and the service ticket noted "ring & pinion gears failed causing whine". Sadly I have much the same whine as before but it's at a much lower decibel level... for now. I don't know if this helps you much... but you have lots of company.
There are three distinct problems I see here that fall into two categories. The first category is gear whine, I've experienced this on other cars. If you're into mods, then you've probably had differential gears changed at one point or another...I've had it done in my Mustang. Anyway, improperly set up gears will typically whine, although, some brands will whine even if set up properly. These differentials seem to be particularly loud.
Your differential didn't fail, it just had a noise. If you had experienced bad whine throughout the RPM range or some other symptoms, then that would definitely had been a sign of trouble. As it is, I have gear whine from about 45 mph to 65 mph. I guess it was annoying at first, but I've gotten used to it.
The differential is not failing, so I'm really not inclined to do anything about it. Then again, NVH problems don't really bother me, nor am I sensitive about squeaks, rattles, clunks and the like. I love to listen to music when I drive, generally, I find that Dave Grohl is much louder than my differential!
The second category is out and out failure of parts. That usually takes two forms. The first is a leaky pinion seal. That's easy enough to detect. You'll notice a puddle on the garage floor if you have it.
Another common failure, which I experienced personally, was a failure of the clutch packs. You'll notice it when you make sharp turns, it sounds a bit like rubbing or binding and you might be tricked into thinking it's coming from the front of the car. If you have it, then you will know it, trust me. The sound is very noticeable and will be pronounced during sharp, low speed turns, as when turning into a parking spot...or doing donuts in the parking lot.
When I backed my car, I have my clutch pedal pushed in and shifter in reverse. I let my car roll down the slope since I don't want zoom onto the road in reverse. That is when I hear that sound too. I haven't taken my car in to the dealership, will do that next time I get an oil change (real soon).
My driveway is relatively flat, I have an auto trans, and I was not applying power and let the idle drive the wheels. It started making noise RIGHT as I started to back up. when I stopped (thinking I was dragging something) I switched to D to try and get the dragged item unhooked, backed up again (no noise, so I figured i unhooked it) and noticed... NOTHING WAS ON THE GROUND! And like mentioned above, it sounded like it was coming from the front end.
There are three distinct problems I see here that fall into two categories. The first category is gear whine, I've experienced this on other cars. If you're into mods, then you've probably had differential gears changed at one point or another...I've had it done in my Mustang. Anyway, improperly set up gears will typically whine, although, some brands will whine even if set up properly. These differentials seem to be particularly loud.
Your differential didn't fail, it just had a noise. If you had experienced bad whine throughout the RPM range or some other symptoms, then that would definitely had been a sign of trouble. As it is, I have gear whine from about 45 mph to 65 mph. I guess it was annoying at first, but I've gotten used to it.
The differential is not failing, so I'm really not inclined to do anything about it. Then again, NVH problems don't really bother me, nor am I sensitive about squeaks, rattles, clunks and the like. I love to listen to music when I drive, generally, I find that Dave Grohl is much louder than my differential!
The second category is out and out failure of parts. That usually takes two forms. The first is a leaky pinion seal. That's easy enough to detect. You'll notice a puddle on the garage floor if you have it.
Another common failure, which I experienced personally, was a failure of the clutch packs. You'll notice it when you make sharp turns, it sounds a bit like rubbing or binding and you might be tricked into thinking it's coming from the front of the car. If you have it, then you will know it, trust me. The sound is very noticeable and will be pronounced during sharp, low speed turns, as when turning into a parking spot...or doing donuts in the parking lot.
I agree with everything stated here. We put new gears into the T/a and they whine and sounds like the rear may be ready to go, but I know it's not. I experienced the whining through the whole RPM band. Nicole's gears are very announced at about 55-60 mph. I told her most likely because during breakin you spent too much time @ those rpm's. But anyways, I don't hink a whine at a certain rpm is going to hurt anything. I just don't understand why stock gears would be doing this so much.
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2003 Dodge Ram 4x4 QC/SB - w/ a 4-horse Bison trailer in tow
mine went, no hint of problems, no noise, no leak, the wife was just coasting off a bridge, basically idling, (she does not like the turbo) & bang!!!! new rear end time.
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