[twa318]

Future reference for anyone who is having the same problem, here is a video I took of what it sounds like when the rear pinion bearing has failed.

https://streamable.com/i9nhjl

You can hear it best last 15 seconds of the video, it was loudest when coasting to to a stop from 25mph

Just got a remanned differential from East Coast Gear Service put in and it’s now whisper quiet.

Another ECGS success story

[SurferUK]

Interesting thanks for posting that. My 2WD makes a whirring sound at 50 - 60mph, it seems to need to warm up a little bit for it to happen. I am hoping it is a wheel bearing or maybe even the tyres as it doesn't seem to change tone whether at constant speed or on the over-run decelerating.

[gaber6]

After I tried replacing leaky pinion seal, I overtightened the bolt and after a long trip and pulling into my drive, I hear the wrrerrchunkachinkaclinkwirrrrchunkachunkaclink.
I had the dealer do mine.. didn't have a garage at the time and cost about $2200

[MikeinNH67]

Curious, did it fail because of lack of gear oil or age? How many miles?

[SurferUK]

Originally Posted by MikeinNH67

lack of fear oil

I'm afraid so.

[frostyflammable]

I am trying to figure out a similar-ish noise on my 04 4Runner, hoping its one of the bearings as it noise pretty much goes away when turning to the right and taking weight off the right side of the vehicle.

[SurferUK]

Originally Posted by frostyflammable

I am trying to figure out a similar-ish noise on my 04 4Runner, hoping its one of the bearings as it noise pretty much goes away when turning to the right and taking weight off the right side of the vehicle.

Could you find a wide open area and knock it into Neutral and see if the noise remains?

[frostyflammable]

Originally Posted by SurferUK

Could you find a wide open area and knock it into Neutral and see if the noise remains?

Sure can, I live out in the country so empty roads for days. What am I expecting if the noise goes away while in neutral, does that mean it's something inside the trans?

[SurferUK]

Originally Posted by frostyflammable

Sure can, I live out in the country so empty roads for days. What am I expecting if the noise goes away while in neutral, does that mean it's something inside the trans?

I have a hunch if it's just as noisy in neutral it's a bearing, you've already done the test of loading up each side. In neutral I think the diff and prop shaft are still turning but not under any drag from the gearbox so if the noise is identical it seems like it wouldn't be the diff. I think so, anyway!

[frostyflammable]

Originally Posted by SurferUK

I have a hunch if it's just as noisy in neutral it's a bearing, you've already done the test of loading up each side. In neutral I think the diff and prop shaft are still turning but not under any drag from the gearbox so if the noise is identical it seems like it wouldn't be the diff. I think so, anyway!

Awesome idea to try, will try it tonight when I get home. Thanks!

[MikeinNH67]

Originally Posted by SurferUK

I'm afraid so.

LOL, good catch and reply, bad proofreading by me.

As for the later questions, a wheel bearing will generally quiet down when you turn hard in the direction of the bad side as it releases some weight off the bearing. Not 100% but can be helpful. It seems yours fits that criteria. Of course, I still replaced the wrong side on mine so it ended up with 2 new front wheel bearings.

I've only seen one diff bearing go bad and that was on my son's ranger. It leaked out all the gear oil and locked up. The pumpkin had a small rust hole in it if I remember correctly.

[SurferUK]

Originally Posted by frostyflammable

Awesome idea to try, will try it tonight when I get home. Thanks!

Let us know, here's hoping it gives you a clue and it turns out to be something cheap and easy!

[frostyflammable]

Originally Posted by SurferUK

Let us know, here's hoping it gives you a clue and it turns out to be something cheap and easy!

To update everyone... while I had to car in for an alignment at a local independent shop I trust asked them to look at the noise... after they test drove it, put it on the lift and did some diag they told me that the rear differential needs to be replaced. Apparently the noise is coming from the differential itself however they did not open it to get a close look as it was close to end of day, but he was pretty sure it needed a new diff. He quoted me $2500 including a new axle, diff and the labor to replace it however I want to do this on a budget. Reading up seems East Coast Gear Supply seems to be the one to go with so I am going to email them see what kind of price we are talking about for a new diff. Never replaced the diff, however seems take axles out, drop the driveshaft, some swearing trying to get stuck bolts out, take way too much time finding dropped tools etc. Not sure yet which way I will go, however will see what ECGS has to say.

I will start a whole new thread once I reach 15 posts to document everyhting.

[frostyflammable]

Originally Posted by SurferUK

Let us know, here's hoping it gives you a clue and it turns out to be something cheap and easy!

I also tried throwing it in neutral while at speed and could not hear or feel any difference.

[SurferUK]

Originally Posted by frostyflammable

I also tried throwing it in neutral while at speed and could not hear or feel any difference.

Have you jacked it up and tried to rock each wheel?

It does sound like a wheel bearing, if it was the diff I wouldn't expect the neutral test to make the noise stop, although I suppose it could, but at the least the tone of the noise should change as everything that part of the drive-line would be rotating freely.

What's your diff oil age and level?