2016 SR5 Rear Differential Noise after 10K miles

[4Rman]

Hello - Disclaimer: I did attempt to search the forum but could not find much on the issue - 5th. Gen/2016 SR5

Right around 10K, I noticed that my 4Runner had developed a whining noise that is audible past 65 MPH. It changes, if I decelerate it get's louder(for a second). It is constant at 70MPH or higher. It sounds like pinion bearing noise or something in the area of the rear differential.

At my 10K service, I don't believe the stealer serviced the 6 zerks per owner's manual (no mention of it on the work order). Question, will simply greasing the zerks eliminate the noise? I have 12.5 K now and am getting ready to take it to the dealer but I am afraid based on past experience, they will try to convince me that I am "hearing things" and that it is normal for the diff to have some noise.

I guess I am trying to find out if this is a known issue with 16' and/or 5th gen. with less than 13k miles. If so, any pointers on making the service adviser conversation more forceful and convincing?

Had so much fun with my stock 4Runner in Utah last July, may be I'll post some pics someday. Thanks.

 

[catrains]

my 2016 T4R is the same exactly as yours.

with 3K miles on it in jan 2017 I changed the engine oil and the rear diff gear oil.

the engine oil was perfect. the rear diff was bad. this is a well know issue since the diff in the rear when new causes the gear oil to over heat. I did not do any long trips when less than 1 K on it just short drives 10 mi or so but even with that light use that diff oil was nasty bad with specks of black floating in it.

so it maybe the diff is the problem. greasing the drive shafts I doubt will fix it.

 

[1engineer]

my 2016 T4R is the same exactly as yours.

with 3K miles on it in jan 2017 I changed the engine oil and the rear diff gear oil.

the engine oil was perfect. the rear diff was bad. this is a well know issue since the diff in the rear when new causes the gear oil to over heat. I did not do any long trips when less than 1 K on it just short drives 10 mi or so but even with that light use that diff oil was nasty bad with specks of black floating in it.

so it maybe the diff is the problem. greasing the drive shafts I doubt will fix it.

Well known issue? On a 4Runner? No. Don't spread rumors you cannot substantiate. That's how misinformation gets started. If you can show us a TSB or a recall or even elevated service visits from some place like true delta then absolutely, I'll believe you.

OP, as far as I know there are no known issues with the 4Runner rear diff. I do concur with [MENTION=138935]catrains[/MENTION] that, if the noise is the gearing, greasing the driveshaft won't help.

My question is this: How do you know it's the rear differential making the noise? Lots of rotating parts are speed dependent with regards to noise.

 

[catrains]

well being a member on here for almost a year and also other forums the reports from owners ''DIY" state the rear diff gear oil is looking bad at less than 5K miles and it was also on my T4R as well when I did the diff gear oil level checks at the engine oil change of 3K miles... so I believe my fellow Toyota members . reports from Toyota ? that would be weird.

on drive shafts I am guessing that over 30 years I have worked on more drive shaft repairs , than drive shafts you have just looked at. I did many of these on big vehicles. that drive train noise if from rear , is the diff. probably a bad bearing because the gear oil was never checked/replaced on fluid condition or level when he had the free service ....LOL.... you get what you pay for ,,, free usually means a screw job in the end .LOL>>.

if the diff bearing is the problem then the rear diff will begin to leak. hopefully for Toyota after the warranty ends.

 

[4Rman]

WOW dirty diff oil at 3K. That makes me wonder?

To 1 engineer, the reason I think the noise is coming from the rear differential is because a while back, I had a 2001 Nissan Frontier and it had the same type of noise. Nissan replaced it under warranty and the noise went away.

It seems constant after 68 mph and varies in volume depending on accelerator release. Also, it seems to be louder when traveling down grade and the load on the engine reduced by backing off on the gas. My perception of the direction of the noise is from the rear of the truck. Thanks.

 

[1engineer]

WOW dirty diff oil at 3K. That makes me wonder?

To 1 engineer, the reason I think the noise is coming from the rear differential is because a while back, I had a 2001 Nissan Frontier and it had the same type of noise. Nissan replaced it under warranty and the noise went away.

It seems constant after 68 mph and varies in volume depending on accelerator release. Also, it seems to be louder when traveling down grade and the load on the engine reduced by backing off on the gas. My perception of the direction of the noise is from the rear of the truck. Thanks.

I would just take it in. Good luck and no, dirty diff oil after 3K or diff problems are extremely rare on these vehicles. Let us know the outcome please.

 

[catrains]

WOW dirty diff oil at 3K. That makes me wonder?

To 1 engineer, the reason I think the noise is coming from the rear differential is because a while back, I had a 2001 Nissan Frontier and it had the same type of noise. Nissan replaced it under warranty and the noise went away.

It seems constant after 68 mph and varies in volume depending on accelerator release. Also, it seems to be louder when traveling down grade and the load on the engine reduced by backing off on the gas. My perception of the direction of the noise is from the rear of the truck. Thanks.

the diff teeth can have a bad machining. or the adjustment of the teeth on how they mesh. since the diff cover cannot be removed [no cover] they will have to replace it . post back what they did or why its causing this.

It would be good if Toyota did have a diff cover so it can be inspected and the box cleaned out. some reported that they had low gear oil level from factory. check the fluid .

 

[4Rman]

I think i read in the 4th gen section that Toyota only replaces the the whole unit rather than just the bearing(assuming that is the source of the noise). I am waiting for the weather to warm up a bit here in Minnesota.

Assuming it is easy to check the differential oil level by the dealer? I think there is one bolt they have to loosen up.

One thing I hate is rattles and noises in new(er) autos. I guess it is a mechanical component and can wear but at 10K, that's a bit disappointing from a vehicle that is suppose to be rough and tough.

 

[BlackWorksInc]

Differential fluid will always look nasty after a few thousand miles. It's not abnormal, particularly in the rear differential and front differentials is where you'll see them get very dark and icky looking.

Brand new units will sometimes have some specs and slivers in them as the bearings and such wear in. The trick is learned what normal wear looks like (very fine specs/slivers with only a small amount of build-up on the drain plug) vs. something abnormal (bits, chunks, wiry looking bits, ect and the drainplug magnet looking like it's growing a second and third head of meal). The rear differential in particular will always look nasty, it's working the hardest and some metal to metal wear is completely normal (which is why there's a service interval on it). Between heat, pressure, and such the fluid will darken; higher-end synthetic fluids will do this as well over time.

We recommend AWD/4WD services at 30k intervals at my dealership and having seen vehicles ranging from their first 30k to their 150k the fluid just looks the way it does. It'll look dark brown and sometimes grayish after a while. The more concerning issue is when it's dark black like used engine oil or "shiny" as it pours out.

We've already had to replace a half dozen transfer cases and differentials in some SUVs and Trucks because people spun the tires on ice/snow and then hit pavement. There was one Tacoma a co-worker worked on where they shattered the ring gear and sent a piece through the differential housing. That's user error, not a factory issue.

I think i read in the 4th gen section that Toyota only replaces the the whole unit rather than just the bearing(assuming that is the source of the noise). I am waiting for the weather to warm up a bit here in Minnesota.

Assuming it is easy to check the differential oil level by the dealer? I think there is one bolt they have to loosen up.

One thing I hate is rattles and noises in new(er) autos. I guess it is a mechanical component and can wear but at 10K, that's a bit disappointing from a vehicle that is suppose to be rough and tough.

Rattles? What rattles are you talking about?

 

[4Rman]

Thank you (BlackWorksInc) for your detailed comments and insight. Living in Minnesota, it is unavoidable to go from snow to dry pavement to snow to ice and everything in between. That's why people love our winters so much!!!

I will say though, I was not sure how the part-time 4WD system will handle the snow but it is very good. Love how it launches in snow from a stop in traffic. All four wheels pulling at the same time makes take-offs in snow much more sure footed even with the crappy stock tires. On the trails in Utah last summer, it also proved it's metal. On a 6 hours trail outside of Capital Reef, I saw two cars the whole time, a 4th. gen and a jeep.

I just hope the dealer does not give me a hard time fixing the noise.

 

[Nastyman]

Am interested in hearing what was found by OP with respect to differential oil level.

I purchased a 2016 Limited 4R in January of 2017 with 2 miles on odometer. I'm anal and decided to check the "hard to get to" fluids at 500 miles. Both differentials were low (i.e., couldn't pinky touch fluid through fill hole for either differential). Needed 3/4 qt to top-up rear and 1/4 qt for the front to raise levels to bottom of fill holes. Probably not low enough to cause damage in short term, but could result in elevated differential temps and more rapid oil breakdown over long term. Transmission and transfer case were okay, though.

 

[bnb675]

WOW dirty diff oil at 3K. That makes me wonder?

To 1 engineer, the reason I think the noise is coming from the rear differential is because a while back, I had a 2001 Nissan Frontier and it had the same type of noise. Nissan replaced it under warranty and the noise went away.

It seems constant after 68 mph and varies in volume depending on accelerator release. Also, it seems to be louder when traveling down grade and the load on the engine reduced by backing off on the gas. My perception of the direction of the noise is from the rear of the truck. Thanks.

I know this thread is a little old but I just brought my 2018 4runner SR5 into dealer with 1200 miles on it for the same exact problem. Highway speed while deceleration or light load there is a moan/whine constantly until you drop below 58 mph.

Master Tech road with me and confirmed the sound from front seat and back seat. He noticed the noise immediately and put in a case with Toyota. I was told to come back following week for a more detailed inspection.

Following appointment, I dropped vehicle off for the entire day. They drained the fluid to check it for abnormalities and it looked brand new. They refilled the rear diff and found nothing wrong. They drove other new 2018s on the lot and confirmed some noise on those also.

Toyota closed the case and said this is a common issue and not a problem for the vehicle. There are just very tight tolerances in the rear diff housing that could cause this on acceleration or deceleration or both depending on the angle of tolerance it is off.

Should I be concerned for longevity or try something myself?

 

[RedSled]

I know this thread is a little old but I just brought my 2018 4runner SR5 into dealer with 1200 miles on it for the same exact problem. Highway speed while deceleration or light load there is a moan/whine constantly until you drop below 58 mph.

Master Tech road with me and confirmed the sound from front seat and back seat. He noticed the noise immediately and put in a case with Toyota. I was told to come back following week for a more detailed inspection.

Following appointment, I dropped vehicle off for the entire day. They drained the fluid to check it for abnormalities and it looked brand new. They refilled the rear diff and found nothing wrong. They drove other new 2018s on the lot and confirmed some noise on those also.

Toyota closed the case and said this is a common issue and not a problem for the vehicle. There are just very tight tolerances in the rear diff housing that could cause this on acceleration or deceleration or both depending on the angle of tolerance it is off.

Should I be concerned for longevity or try something myself?

I think as long as it has been logged in to the records you are good.

 

[bnb675]

Yeah but I will be going on a long highway trip soon and it will annoy me the whole way.

I see you have a 2017, do you have any noise like that?

 

[17KT4R]

Toyota closed the case and said this is a common issue and not a problem for the vehicle. There are just very tight tolerances in the rear diff housing that could cause this on acceleration or deceleration or both depending on the angle of tolerance it is off.

Should I be concerned for longevity or try something myself?

I think that is an acceptable diagnosis and assumption to come to. While I have the locker rear end I think that I can make out the same whine going on at light application of throttle at those speeds, I cannot reproduce it coming off the throttle however and it depends on weight in the vehicle too. I've heard it since new but we have very few stretches of decent highway pavement around here its tough to keep hearing. I think a lot has to do with the poor floor insulation, thin carpet, a lot of road noise comes through at higher speeds and this slight gear noise or whine coming off the long drive shaft is nothing to be concerned over. I'm not but I'll probably change the fluid on a severe duty schedule anyway just for peace of mind.

Make sure your tire pressures are at 35psi maybe too, I had to lower mine when new they had them up almost at max inflation levels, maybe for better mileage but the tire noise changed when they got softer (more quiet), less road amplification.

 

[Shadytype]

Yeah but I will be going on a long highway trip soon and it will annoy me the whole way.

I see you have a 2017, do you have any noise like that?

I have the same noise. I reported it last weekend at my 5k service (joke).

It WAS NOT noted on my work order.... but service advisor said the diff whine is normal. 2018 limited here.

I will ask for it to be noted on next service.

 

[bnb675]

It's noted on my service records but I bought this as my first Toyota not to have to worry about this stuff.

Guess I was mislead and all mfg have there issues

 

[stevo2vabch]

Yeah but I will be going on a long highway trip soon and it will annoy me the whole way.

I see you have a 2017, do you have any noise like that?

I have a 2016 SR5 with the same exact issue/sound. I thought maybe I was just going crazy and it always made that sound, and for some odd reason I didn't notice it at first. This now confirms I am not going crazy. I want to say mine started at around 8000 miles and now has a little over 11,000 miles on it now. I had it to the Dealer a couple of months ago for it's 10,000 mile service and requested they check out the sound I was referring to. They claim that they couldn't really hear anything and anything that they did hear was normal. I really want to put wheels and tires on it but I am afraid if I do that and something happens to the rear-end they will deny it and say it was the bigger wheels/tires.

 

[bnb675]

I was told if they replaced the rear diff, because it's a 1 piece unit, I could end up with a worse noise at different speeds and/or at acceleration instead of just highway speeds during deceleration.

Disappointed

 

[RedSled]

Yeah but I will be going on a long highway trip soon and it will annoy me the whole way.

I see you have a 2017, do you have any noise like that?

It's hard for me to tell, only have about 7,000 on her.