Rear diff # 3. Howling

Do you have a link to the complete instal instructions for the tsb?

 

Type in the tsb number on google and look around you’ll be able to find it. You’ll have to download the link. I don’t know how to send it. The number is in the top left corner of the page.

 

Is that tsb for access cabs to, or only just double cab trucks?

 

Just double cab. Is your truck an access cab? Probably would explain why you don’t hear anything

 

Toyota places a damper on the 3rd member of the Hiace, which uses a version of this axle.

 

Weird they don’t do that on tacomas

 

Put a pool noodle between the bed and cab. Any sound you are getting is being direct right up and into the rear cab vents. A pool noodle will minimize the sound making it to you

 

What happened to the OP. He drop this bomb and left everyone else talking to a ghost. just saying

 

Acording to the owner of that truck, he's had the dealer replace the diff a couple of times, and it did not improve, in fact it may be worse than when he started.

 

It’s because it’s in the build of the body that’s causing it. A new rear diff will make no difference, do the tsb and basically live with whatever noise Is left after .

 

That seems to be the consensus.

 

Yep, access cab. got gypped again.

 

That would explain it then.

 

Geez, that second sound clip would definitely drive me nuts.
My 2019 Limited 4x4 auto has the smaller rear end and a different ratio (3.90???) and it is still silent at 60k miles.
I’ve done a lot of gear swaps and changes, lower gears tend to make more noise. I worked at a Jeep dealer and the DANA gear sets were terrible. Damn Axle Noise Again was what we named them.
It would be interesting to do a gear pattern check and see how well the gears are set up. I put some 4.56 gears in my friends Ram HD and even with a painstakingly precise set up they make some noise but it was from the get go.
I would have the vibration damper and foam pad hack done, maybe it would be livable.
New vehicles have tuned mass vibration dampers all over the place, on the exhaust, the rear diff, the frame.
The late model Lincoln MK-C has a ten pound rubber mounted damper INSIDE the tailgate!

 

I saw it coming a mile away,, but it's TW so it's a good guess at this point.
I mean come on man, the dealer has replaced 3 axle assemblies??

 

Funny how when aftermarket gears are installed, there is a break in procedure. It’s usually something like 20 minutes of run time while on jack stands. They a fluid change. Then another fluid change after 500 miles or so. Toyota recommends none of this.

I can say this, at 5k, I replaced diff fluid

 

my 23 doesn't do it.

 

You might have a point, mine started at 7000. I was perfectly quiet before that, changed fluid the 1st time at 10,000

 

Yep. Can confirm. Put one in there in Jan of 23 with 1600 miles on the truck at neighbor’s recommendation. Over 50k now. Took noodle out Saturday night to de-mud the truck. Forgot to put it in on way back to hotel. Definitely noticed.

 

Actually looking at records, it changed it at
7995. The magnet was clean, no large glitter in the oil. Some very fine metalic dust present, but again, very small.