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

Do they ever pull the cover and check wear pattern?

 

I was told they shipped the old rear diff back to "the lab"....so their engineers can take a look at it. Tacoma World is a very small sample size but the Poll numbers here don't lie and if there are half a dozen folks here alone that have already had theirs replaced just extrapolate that sample size into the general public and that speaks volumes. I have a very strong suspicion that Toyota is already ALL over this one and just working on trying to find the best solution. Hopefully it is a driveline issue they can resolve and may also address the vibrations people are experiencing.

 

Yep. I recall a poster that test drove every new Tacoma on the lot, and was able to hear it. Dynamat and an upgraded stereo has made mine much better.

 

I also had my rear diff replaced once already. Currently my dealer is try to schedule a time when the regional field engineer (same one that looked at my first diff, and gave the ok to replace it) to come look at my second one. I am really interested to hear what he has to say this time, as everyone at the dealership is thinking that this may be a manufacturing issue now.

 

When I buy a used vehicle I will try to pull dealer records on the car so I can see what type of warranty work has been done, maintenance etc. Red flags would go up if I saw a used vehicle that had a rear differential replaced and especially if it had been replaced twice. Certainly not something most folks would really be thrilled to see on a vehicle history sheet...of course there are a lot of people who will never go to that length to check the vehicle history like that. Who knows.

 

You should go on vacation more often; you seem more optimistic these days.

 

TRD OR DCSB 6MT.

It howls. Mine is between 46-52 mph at its peak though

 

Well I just returned from my Toyota dealer and I have to say, WOW! I went for a ride with the Toyota drive line guy, I was all prepared with information gathered while reading this post BUT after about 1/2 mile at highway speeds he says. "ya you need a new rear end". Now if it had been a Ford I know I'd still be there arguing my case. If all Toyota service is this good I have not bought my last Toyota. (This is my 1st) Parts ordered today (Friday) and should be here Monday or Tuesday. A loaner car will be waiting.
I would like to thank all of you who posted information on this topic. My opinion is if you have a Tacoma with a howling rear differential, make a appointment with your local service dept. You just might be surprised how good Toyota service is.
Tom

 

Aero are you doing the diff fluid flush or did dealer offer it?

 

Keep us posted! I really hope that the replacement actually fixes the issue for you! I hope that it is just that simple, and that myself and some other forum members just got double unlucky getting two lemon diffs....but sadly I just don't believe this is the root issue.

Glad to hear that your dealership is treating you well too!

 

No, i really, REALLY wanted to do it when I bought it new. I went back and forth with myself over it and finally made the choice that I would follow exactly what was in the manual so if anything failed, there was no way they could blame me. Especially since I would have switched to a quality brand

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

75W-90 (for ease of finding it) instead of Toyota's 75W-85 (which is damn expensive). I just wanted to play it 100% safe.

Any, and I mean any shop that does re-gearing or any of that type of differential work specifically states that you need to switch the oil out after the first 500 miles and if you don't do it, you void their entire warranty. So if I get another diff, I'm switching it out after the first 500 with a quality 75W-90 fluid. Tight tolerance gears generate a lot of excess heat due to friction when they are breaking in so it puts a lot of wear on the fluid, dramatically reducing its ability to lubricate properly.

 

Called today about mine and was told that the parts will be in in a week or so. They also said that the tech line said that there have been quite a few replaced already.

May have had a new guy on the assembly line or the specs are just a hair off. Either way I expected some bugs from a first model year truck and the warranty will cover it.

 

Ya, I hope it fixes the issue. The service tech and I talked about the other issues raised in this thread, but was pretty confident that there was a problem with the differential, as do I. The plan is to get it fixed. If the new rear end doesn't do it, he is going to address the other possible causes. I will keep all updated.

 

Nope just took the service manager and the lead tech for a ride and I didn't even have to say anything. They just said "it is the rear diff we will call tech and get one ordered".

 

They flushed the fluid a couple of times when they put the new diff in mine (supposedly), as they were still hearing the noise after replacement.

After driving for a couple days I've determined that it is just as loud, if not louder than before. At this point I guess the best course of action is to get it documented again and wait for an actual fix from Toyota.

 

A work colleague is on his second replacment rear on his 2016 TRD 4x4. The last one that was installled is now louder than his original rear end after 4K miles. What a mess.

 

Still on my stocker. Been under water 20-30 times.

 

I JUST got my TRD OR 6spd MT last week, under 200 miles, and I think I have this same diff whine. It sounds almost identical to my old M3 I had in college, which ended up needing a new driveshaft to fix the whine because the old driveshaft was bent slightly out of spec (EDIT: the M3 whine was SUPER loud, and super annoying, nothing like the faint whine I hear now). Obviously this seems like a highly prevalent problem in the new tacos.

I said I THINK I have it, because I have not been on a long road trip yet, and I'm not sure if it's the wind howl from the front control arms or the diff, but it seems to change with slightly load changes on the diff (road gradient changes while in cruise control, or me feathering the throttle to try and produce it). It's quiet but it sounds identical to previous diff whine I've personally experienced. Hopefully Toyota will fix the issue soon! I'm headed on a road trip today so I'll investigate the sound more thoroughly and report back.

Other than the whine, I have none of the other reported issues with this truck. Shifts great, feels great on the road. Get a lot of compliments!

 

Yeah I think if the whine does not get worse over 5k miles or so we would probably be ok just living with it....for those of us who have a faint howl that is. But in my case it got louder from 5 or 6k to 12k miles to the point where I could hear it over my radio. At the end of the day it's just not something I consider to be "right" with a vehicle that costs this kind of money and has such low mileage....catastrophic failure or not it isn't something we should just have to live with.