2008 Toyota Highlander making humming sound at highway speeds

toyota
noises
highlander

#1

My 2008 Highlander makes a high-pitched humming sound at 70MPH. The sound is not very loud, but I am concerned it indicative of pending engine problem. Toyota put sensors on the car, found the sound was coming from the engine and replaced the transfer assembly. This did not eliminate/change the sound. Now they are saying it is a characteristic of the model and will not repair it. Any ideas would as to what is might be would be helpful.


#2

I also have the 2008 and have the exact same problem. It almost sound like a classic case of worn out RR axle. But this car is a FWD and does not have a rear end. If you give a little bit of gas and it goes away. it happens around 60-65mph. I took it in for service and of course they did not find anything. There is also a noticeable click sound when I first back up the car at the morning. I am not sure if these two things are related. Again the dealer can’t hear it and cannot find the problem or they don’t want to fix it.


#3

Does it vary with engine speed or road speed?


#4

You neglected to tell us how many miles are on the odometer, but I am going to give my opinion that the tires are the likely source of the noise.

Many car manufacturers (sad to say–Toyota in particular) supply their vehicles with tires that are…let’s just say…not of the highest quality. Once these tires have bit of wear on them–typically, more than 12,000 miles of wear–they frequently become very noisy, particularly at higher speeds. These OEM tires are frequently also not very good in terms of wet road traction/winter traction/tread wear.

If your OEM tires are typical of the ones that Toyota places on their cars, they will be ready for replacement by ~20,000-24,000 miles. You might want to give some thought to replacing the tires sooner, rather than later, if the noise is really bothersome to you.

If you go to www.tirerack.com you can see the characteristics of all the tires available for your model, and this will enable you to select tires that are noted for less road noise. Even if you buy your tires locally, the Tire Rack website will help you to select a tire that meets your needs.


#5

I agree with the tires being a source of noise…I never have had a new Toyota (6 to date) go more than 20,000 miles on OEM tires…and have changed them out for the tire rack recommended tires every time…


#6

Thanks to all who responded. My car has 30,000 miles on it, but I noticed the sound around 15,000. I am not sure if it was making the sound from the beginning. It happens consistently around 70mph. If I speed up or slow down, I don’t hear it. It is not the tires since I just had them replaced and it makes the same sound after putting new/different brand of tires on the car. Toyota put sensors on the car and determined it was coming from the engine, but since replacing the transfer assembly, they say it is solved. It is not.


#7

“Transfer assembly?” There’s nothing I know of on the engine called a transfer assembly. A transfer assembly sounds more like something in the drive train. Is this vehicle FWD, 4WD, or AWD?


#8

The service person I was dealing with told me the sound was coming from the engine and they wanted to replace the manifold, but after talking to the corporate technical support person who put the sensors on my car he wouldn’t let them replace the manifold and told them to replaced the transfer assembly (yes, part of the drive train). He said there was too much space?? After replacing the transfer assembly, I took it back with the same sound. Again the corporate support person said that putting in a new manifold would not fix the problem and the car was working as designed…I think they know they have a problem with this model and don’t want to open a can of worms. By the way it is 4WD.


#9

Actually, your Highlander is AWD, not 4WD.


#10

People can get so wrapped up in this “new car with strange noise that signals impending doom” senario. I have lost many dollars chasing down these type of noises and if you don’t find a cause (hard when there is none) you don’t get paid,and when I don’t get paid I am not making any money for the Dealership. We all loose.


#11

I also have a high pitched humming noise that starts at 70 mph. Mine is a 2006 FWD V6 highlander. Started at about 70,000 miles. Now I have 83,000 miles and have a lower pitched humming noise that occurs at 55 mph. I am on the third set of new tires and still have the humming noise.