noisy diff

wanted to know if anyone ever found a fix for the notorious howling diff issue on these damn trucks. I drove through mud once and now it won't shut up, 13k miles were perfect until it started making noise.

 

Whats the fluid look like?

 

i haven't checked yet as i started on sunday but i'll take a look when i get home, what shouldn't it look like ?

 

Not much you can do because its resonance. I had mine swapped out from the dealer and it started howling right out of the parking lot. Someone on here stated that if you change something in the rear end ie. leaf springs, shocks etc it might go away. My sweet spot is 53mph.

 

…I even changed my diff oil to Amsoil severe gear 500 miles after the new one was installed.

 

Was 56 for me, but the rear locker had been slow to engage and when it finally stopped engaging I took it to the dealer (20k miles).

Replaced under warranty and so far there’s been no more whining and I’m at 23k now.

 

What stopped engaging?
Locker?

 

Yes, sorry I wasn’t clear.

The locker wouldn’t engage at all, the red light never came on solid- only blinked.

 

Weird.

 

Agreed, and no issues at all at the dealer, came out and told me they were swapping it under warranty and they’d be happy to get me home. No issues since- whining or engaging.

 

that's weird oddly enough i've never used my locker since i bought the truck. how fast should the locker engage ?

 

ive also heard harmonics was the main issue but that just sounds like an excuse to upgrade my suspension

 

Not a terrible excuse!

 

There’s quite a few threads on here that go more in depth on this topic.

 

If you are sitting still it could take an infinite amount of time depending on a few factors. If you are driving slowly (< 3mph) it usually takes only a second or so.

 

Here is a big thread with lots of discussion on the topic going back to 2016.

https://www.tacomaworld.com/threads...oise-howling-when-feathering-throttle.442341/

 

Mine has howled since I bought it with 7 miles. Does it from about 52-58mph under real light throttle. You’re saying that’s not normal?

 

it shouldn't be considering it never made that noise for 13k miles, it stated this sunday on my way home when i took it mudding

 

Can you share more details about this “mudding” episode?

A more detailed description of the noise you hear would be helpful as well.

 

I've been chasing this issue since i got my Tacoma in 2020. bought new and had it regeared to 4.88s. the new gears made an awful noise at freeway speeds and the shop ended up redoing the rear gears again 1 year later. it still had a very loud harmonic hum at freeway speeds. things i did to remedy the issue.

• replaced gear oil with Lucas 85-140
• installed Tacoma Dynamic Damper onto the rear cab mounts Part# 51229-04010 x2
• installed Dynamat sound dampening material against the back cab interior and back half of floor. i also used the closed cell foam on top of the Dynamat.
• Installed beefier tires, these tires make more road noise and drown out the diff hum.

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After all this, i can still hear the gear whine / hum a bit but it's much improved. it really doesn't bother me that much now. i would at least start with a thicker oil, its cheap and easy to do. the thicker oil will cushion the gears so they doesn't resonate as much.
The dynamic dampers helped a little but not as much as i would have liked. some people have better results with these than i did.
The sound dampening material helped more with road noise than the actual gear hum but still helped a little.

this was a lot of work but everything combined helped mitigate the noise.