3rd Gen Poll: Rear End Noise howling when feathering throttle

There is a very good post somewhere up in this thread that summarizes what is likely going on with vibrational harmonics coming from the rear differential. IMO, this is not a fixable problem, nor is it likely to impact performance and safety of the vehicle. My truck does this and its most prominent under a towing load. It comes and goes with at defined time intervals while at constant speed so I think its a true harmonic as opposed to inappropriate wear. Moderately annoying but I am not concerned about mechanical failure like I was with my V6 Rav4. Now that HOWLED. I'm leasing my truck and if it proves to be too much I'll go in a different direction at the end.

 

You may be right in some cases but as an FYI I had excessive shavings in my diff analysis. I think some are bad but I’ve yet to hear of one grenading. I’ve had that before as a kid. Quite an experience.

 

I'll bet that was freaky as all get out, especially at speed. I'll ask the dealer when I go in at 10K if gets worse...

 

I was just a 16 year old kid in the mid to late 80s and the diff grenaded and seized in an old Chevy truck. Luckily some gas pumps at the local gas station were there to stop me.....man that was a mess.

 

My 2018 sr5 2wd has had this howl since I got it, in march last year. I have been trying to scan through this thread but its 257 pages so what's the general consensus?

It seems to randomly happen when accelerating through 35-45 and doesn't stay around if I feather the throttle. I never really cared since its a lease and ill be turning it in but I plan on getting an purchasing and OR4x4 at that point.

 

Harmless harmonics

 

The dealership just tried to tell me the fuel pump whine is a normal operational characteristic of my truck, not the rear-end they replaced. Not one of the tacomas we test drove on the comparison had that noise. Ugh....frustrating.

I don't have another vehicle I am remotely interested in, but I don't want to live with the rear end harmonics or fuel pump like noise either

 

Hope so. Need to keep this thread alive in case someone has a eureka idea. I think it could be some harmonic interaction between differential and frame but who knows.

 

Hard to know for sure with the background noise in the video, but it seems to come and go at defined intervals similar to what I experience with my truck when its under load. I think it's the same sound and likely the same source. Once the RD wears to a certain point it has harmonic interactions within the case or with the frame. Seems like there is no permanent fix to this annoying issue.

 

I created my account on Tacomaworld to share my experience. I own a 2018 DCLB SR5 Tacoma, Ontario, Canada. I have the rear-diff whine around 60mph (or 95kmph). Brought my truck to the dealer and the service manager rode with me and acknowledged the noise. They looked into the leaf-spring dampening TSB but my truck already had it installed from the factory. They had a Toyota engineer come in who diagnosed the problem lying somewhere with the rear-diff. They ordered a new rear-diff (took over 1 month to come in) and replaced it in my truck. Afterwards the service manager told me the pinion-angle was out of spec and not set-up properly which was causing wear and tear on the diff, which in turn was causing the noise. My new rear-diff had the same noise driving back from the dealer, but it was almost no longer noticeable. It stayed quiet for a couple hundred kilometers or so. The whine is now as loud as it was previously on the new rear-diff at the exact same speed range. I have not had time to bring it back in yet, and have not opened a case with corporate yet.

 

Like yourself, people have had their rear ends replaced only for the howling to come right back a few hundred miles later. If you were one of the lucky ones, the howling noise isn't as bad as it was before. Others have stated the howling was "worse" than before. If your dealer installed the rear diff correctly according to manufacturer specs, what do you propose is the issue here? This thread has been going on for over 3 years and unless I missed it, no one has actually seen any ill effects from this noise---other than the grenaded diffs (which IIRC were due to low fluid or just frank disregard for a differential)

 

If you open a case prepare for the "this is a normal characteristic for a Toyota truck and we good willed the replacement and won't do anything else" reply.

 

welcome to TW I see you haven't yet posted in the new member thread https://www.tacomaworld.com/forums/new-members.19/ and went directly to the 3RD GEN Rear howl thread for ur very first post here.

 

https://www.tacomaworld.com/threads/taco-sets-august-sales-record.628029/

 

Cool, they still sell trucks. What’s the point of that link here?

 

Lots of trucks that will be great for most and really annoying to others.

 

They replaced the diff on my old 2011 and the noise went away. They refused to on my 17' OR. I have learned to just drive faster or slower than 60mph, and/or to turn up the tunes... let us know if you get anything resolved.

 

point is in spite of all the hand wringing about its a characteristic inherent to the truck controversies 3rd GEN trucks are selling faster than they can make them, and they wouldn't be breaking monthly sales records if anyone believed any of whats been posted.

 

Few people are reading the tacoma forums before purchase. Also, it’s the sort of noise you’re likely not to notice on a test drive.

And the Tacoma’s have a legendary reputation, that Toyota is trying to ruin with issues like this diff howl

 

so the noise doesn't show itself till after you purchase the truck or your just making excuses for not doing a thorough test drive and reading reviews on the vehicle and making a educated decision on buying it or not, that's your fault.