Rear Diff whine again

Exactly. Also there have been people that have had the diffs replaced 2 times and still same noise. So 3 diffs were bad? Don't think so. It's harmonics and some trucks seem tuned differently to the noise.

 

3 diffs could easily be bad if the tooling is worn at the factory - like the last couple years of the rover v8

 

Oh man, that's a stretch. Toyota is not Land Rover lol. That's like me saying "I might be hit by a meteor if I go outside." Yeah I might but what are the chances. Very few Tacomas have this problem.

 

Idk man, i just submitted a complaint to my local dealer for 15!!! Problems on my brand-spanking new taco

 

I remember on a thread awhile ago one guy said he sprayed his leaf spring with fluid film and the whine went away...I am going to try this!

 

Not sure if it makes anyone feel better, but the rear diff whine first started rearing it's head with 2nd Gens. If Toyota hasn't figured out a real solution for this by now, I wouldn't hold my breath that it's going to happen anytime soon.

 

I honestly think a lot of the “issues” is that because the 3rd gen is so much quieter inside than the 2nd gens it makes sounds like this way more noticeable.

 

I use Fluid Film and ACF-50 for corrosion control on my truck.

Rear end whine was significantly reduced when I first applied it.
As in I have to listen for it with the radio off to notice it is still there.
Every time I have to turn the radio up to drown it out (about every 6 months) I know it needs another shot of ACF-50 or Fluid Film to the rear leaf springs.

 

This
My Silverado did it for 250k miles. More cab noise in that truck and you really had to listen for it.

 

my 2019 OR 4x4 DC with 4000 miles has done it now for a while. I have read all the above and am convinced there is no issue and it's just an harmonics thing. i wanted to bring it up to the dealer when i get over that way but i rarely am. once i do, i plan on changing out the diff fluid just to get the shavings out of it from being new and breaking in.

 

how about use thicker gear oil? 80w-140?

 

I was gonna say that too. Maybe not as heavy as 80w-140. I replaced mine with

$29 75w-90 Synthetic Gear Lube - 1 Quart (Pack of 2)

75w-90 Redline at 4k miles and don't have any noise. Mine was also underfilled from the factory by 0.7 qt.

 

I have it, only sometimes though when on the throttle. My 16 didn't, but my 19 does. Doesn't really bother me as it isn't too loud (sitting at 10,000 km, and noticed it within the first 1000).

 

Mine has 10,000 on it and has been doing it all along.

 

I would try a good synthetic gear oil

 

I run 85w-140, synthetic, with REM 5.29 gears, and it will whine in certain situations at certain speeds with specific throttle input.

I think there is more to it than most people think

 

I'm 600 miles in on a regear to 529's including suspension upgrade and deaver stage 1s. New ridge graphs as well and, riding with the rear seats folded down. Getting turbo sounding whine on any coasting but it doesn't do it throttling. I've got 75-90 amsoil to use on the change and hopefully it will diminish.

 

On another thread,some guy said when he put in a bed mat the whine was reduced.

 

2019 SR 4x4,diff whine at 500 miles,took to dealer at 2600 miles after reading other posts,also took tsb#to show them,tech rode with me confirmed noise.toyota had them record it.this was yesterday,toyota told them replace diff,got truck back today with diff replaced,and noise is gone completly.keeping fingers crossed that it doesnt come back,and thats the end of it,

 

2019 Trd Off Road, The diff whine was loud around 1000 miles. Toyota replaced it at 2500 miles and it was quite until around 13k. I have 21k on it now and I installed a flow master exhaust and you can hear it over that at different speeds. I don’t know if I should bring it up again or not being the dealer said unless it is really loud Toyota won’t replace it.