"whirring" noise while driving light throttle. UPDATE!!!

With my earballs

 

how can you deduct that there is a faulty design or install job? do have any facts or its just your personal view, cause telling someone they have a faulty designed/installed diff isn't the proper response when you don't have verification from experts, if it truly was a faulty rear diff there would be a nationwide recall to replace all trucks rear differentials whether they have noises or not. having a bothersome noise and a faulty design are 2 different things, either way there has not been a rear failure due to a howling noise to date, just that it annoys folks

 

exactly, there really isn't a way to measure it scientifically so we just throw out these wild unverified statistics

 

Yeah but these guys sound so smart lol. Pretty sure Hertz is a rental car company to most of them...

 

First determine my wheel's revolutions/second at 45 mph (the speed where the noise appears to be the loudest on my truck). [45 miles/hour] * [5280 feet/mile] * [12 inches/foot] = 2,851,200 inches/hour. Convert to inches per second: [2,851,200 inches/hour] * [1hour/3600 seconds] = 792 inches/second. My tire is 28 inches in diameter, so the circumference of the tire is 28 * pi = 88.96 (rounded to 2 sig figs). My rear wheel's revs/second = [792 inches/second] / [88.96] = 8.9 revs/second. I am unsure, but I believe the ring gear has 39 teeth, causing 39 gear tooth meshes per revolution. Thus gear tooth meshes/second = [8.9 revs/second] * [39] = 347 gear tooth meshes/second. If each gear tooth mesh event makes a similar sounding noise, then there are 347 of these noises per second. Thus the frequency of the howl is 347 Hz.

https://youtu.be/xzNOxYisN6E

 

your formulae is wrong based on the numbers and formulae you have provided here the noise level is under 200hz which cannot be perceived by the human ear,sounds emanating above the 300hz range are barely audiable to a human ear to begin with.

 

Prove it.

 

I wish I didn't have my rear diff replaced. My second diff is about twice as bad as the first one.

So in my case a "free" diff was a bad thing.

Its all a gamble. Could be a new diff solves the issue too.

 

just like most of the non factual evidence you provide, your going to have to just take my word for it

 

What the f*ck are you even arguing with me about?

I said it sounds like a 400hz tone. I listen to my howl every day. Then I listened to different tones and found one that is close. Others have confirmed that this is roughly the sound they hear.

I was helping someone troubleshoot.i wasn't writing a peer reviewed research paper. I wasn't putting out unverified statistics.

Seriously what is your point with arguing here? To prove my exact frequency is off? L O L

 

Yeah that guy is going on ignore.

 

3.909 gears are 11:43

 

Close enough for govt work

 

Should I change my fluid at 500? I can hear a faint howl. I'm already on my 2nd truck ha. The dealer acknowledged the first one was defective and needed to be replaced. The service document stated. " customer states faint howling noise at 50-55 mph. Check and advise." Tech " noticed faint howling sound and deemed to be normal. Took another 2017 Tacoma 4x4 TRDOR for test drive. Same sound present." For the 2nd time around lol

My train of thought is to swap out my fluids with a superior product like Mobil1.

 

I think some people have already swapped out to heavier weight 75w140 and it may have helped, I would do a search and find out more about switching a different weight gear oil other than what the manufacturer recommends, doing so could hurt your chances(warranty) if any other issue to the rear diff arises.

 

I also went to the dealer today to have the noise evaluated. The technician was an older gentlemen and he could not hear the noise on our test drive together. I'm sure they think I am crazy but my wife and friend confirmed they could hear it. Regardless, they put it on the lift to inspect it and sprayed some brake dust cleaner or something like that on the rear drums which did nothing.

 

Next visit they'll probably admit they hear it then will claim it's normal for the vehicle.

 

I'm had the same problem with my brand new 2020 Tacoma. Brought it in to the dealership and they verified the noise. They replaced the rear differential and the noise is gone. Thanks for the help!!