Howling noise at highway speed

My 2018 has howling noise at highway speed ,it starts around 68 mph and it is worse when I decelerate.I have this noise since day 1.I bought this truck brand new,now I have 10000 miles noise is still there,does anybody resolve this problem

 

Sounds like it could be a different issue, but when I got mine, I had a loud whistling at highway speeds. Turned out to be the plastic on the side mirrors was not snapped in correctly and there was a gap underneath.

 

I will check that thank you but I think is more drivetrain related

 

I would take it in and have them check all fluids.

 

THEY CHECK ALL FLUIDS ACCEPT TRANSMISSION FLUID

 

I have the exact same problem as the OP. Started at about 1000 miles on my 2018. Really bad from 67-73mph. It stops when I get over 75mph or below 67mph. It sorta squeaks or chirps a little when you let off the throttle in addition to the howl.

But it also shows up around 30-35mph in town if I'm going downhill with light throttle.

Haven't taken it in yet to get looked at. I think it's the rear diff. Tacoma's have the exact same problem.

 

I think noise is comming from rear end also.let me know if dealer finds anything

 

I can’t hear mine over the tire howl (heh-heh).

 

Perfect solution for the others! Louder tires

 

Rear end is shot. We have one in the dealership where I work with the same problem. They pulled the drain plug and the oil was full of metal. Thing is, The rear ends are, or were, on back order. Good luck, and post your results.

 

Do you happen to know if it's the same rear diff used in the 3rd gen Tacoma?

If the diff is replaced, is it back to "like new" condition?

 

What would cause this failure in a brand new truck?

 

No, tacomas have a rear diff whine thats 75% remedied by replacing some body mounts on the rear cab and putting some sound deadening behind the rear seat.

They also have a diff seal leak.

A howl at high speed, worse on deceleration is more than likely driveshaft related. Where? I don't know. Maybe needle bearings in the front or something like the Tacoma.

 

There's two different sized rear ends in the third gen Tacoma. A 8" and an 8.75" with rear e-locker. If i had to guess Id say yours is an 8" as well. Third member should be totally swappable with a Tacoma Sport or SR5 Third with the same ratio.

 

I may be way off here, but one of my cars (not the 4Runner) had a howl in the rear that was bad enough that I took it to a mechanic to check the wheel bearings. They didn't find any play so they swapped the back tires to the front, and the noise moved to the front. So we concluded it was the tires. You may want to try moving the tires to see if the noise changes...

 

Not tire related. I've changed tires from stock and the sound persists.

 

I did same thing changed tires and noise is still there.Noise is present in 2wd also 4 wd.

 

Rob - Should probably go back to the dealer and tell them your reading about a lot of known rear differential issues in the 4Runner and you have a loud whining. I don't have a lot of faith in dealerships going looking for issues that don't up and smack them in the face but the vehicle is new. If you do please post back your results with them. Even if you want to PM me that's fine also. Just because I also have a '18 no noise just would like to know for future reference. Hmmm I'm beginning to wonder about the "bullet proof" Toyota brand.

 

I scheduled appointment for Monday.I will post results and let you know what TOYOTA dealer said

 

Ill have to ask the service dept if the rear end has an e-locker or not. As far as I know, Toyota is replacing just the 3rd member.

 

If they have any trouble isolating the problem maybe clamping a go-pro underneath on one side forward of the rear axle might reveal something in the audio.

 

The pinion gear was shot. Set up wrong from Toyota. There were 31 on backorder so something is going on. The 4Runner was a SR5 so it was the standard 8" , non E-Locker rear end.

 

Thank you for information I let them know on Monday

 

Do you think you can get further info as to whether the pinion was burned versus stripped?

 

Someone on the Tacoma 3rd gen forum with the same problem said they removed the rear diff and discovered that the pinion angle was off. Lots of metal in the fluid. Replaced the rear diff and after lots of miles, the sound hasn't returned.

Here's the diff howl megathread.
https://www.tacomaworld.com/threads...oise-howling-when-feathering-throttle.442341/

Here's one of many threads about the tsb.
https://www.tacomaworld.com/threads/new-tsb-whine-noise-from-rear-of-vehicle.532809/page-2

 

Megathread is right. Wow 250+ pages. Let's hope this pinion problem doesn't become commonplace in the runners...

 

Could just be normal 4runner noise, chassis dynamics, etc... but Check the mud skirts inside the front wheel wells. They have been known to cause noise issues. Good luck at the dealer, hope they find an answer for you.

 

Just came back from dealer,it is pinion bearing what makes that howling sound/dealer will replace whole rear differential.They drained gear oil and was full of small metal pieces.Rear diff are on back order so I have to wait about 4 weeks.I would like to say thank you to all members of this forum.I will post info after next dealer appointment.They said it is factory defective unit.I hope this info will help people who experience same problem

 

What did they give you to drive till they get the diff in?

 

Thanks for the follow-up. That's pretty terrible to have happen to something so new. And then to have a 4 week backorder. I hope you provide an update afterwards. Good luck...