Tire noise or bearing noise

Darren Technician Wisconsin Posted   Latest  

This is a general question and follow up to my nvh

question a couple days ago. 

How do you guys, generally speaking, differentiate between a tire and bearing noise.

I need to document my results of testing for proof to the customer.

Do I need an nvh kit for this, or is some other method preferred?

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Shane Owner/Technician
Alberta
Shane
 

After a test drive I'll put the car on the hoist with a tech inside. Have him drive the vehicle at different speeds while I listen to each bearing with a stethoscope. It's been helpful finding noisy difs and transfer cases as well.

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Tom Owner/Technician
Tennessee
Tom
   

Experience. While the noises can be a little similar, there are some differences. But it also depends on the current severity of either. Very early bearing failure can at times be hard to distinguish from tire noise, especially if the tires also have some cupping. Bearing noise seems to me to change much more in it's tonality with speed increases or decreases than tire noise. Front bearing…

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Glenn Owner/Technician
Texas
Glenn
 

Hi Darren, There are smart phone applications available now and you can send the results to your computer to print them off. Conventional NVH kits are pricy, but I will say they are more accurate from my experience. PICO has one of the best on the market. My question is: Do you do enough of them to justify the cost? If it is just one customer, fire them and say good bye. They can always take it…

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Sherman Owner
Texas
Sherman
 

I sincerely hope you fired the customer.

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Glenn Owner/Technician
Texas
Glenn
 

Hi Sherman, He actually swallowed his vain desires to look cool and had me install the original mirrors back on the vehicle. Noise was gone. After an informational conversation, he took my advice to research automotive wind tunnel testing. He came back a few days later awakened by what he found. When I asked him how much information he found about aftermarket testing he said there was very…

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Sherman Owner
Texas
Sherman
 

Yeah, human EGO is a mystery. The motivational speaker, Rick Rigsby says “Ego is the anesthesia that numbs the pain of stupidity”…

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Glenn Owner/Technician
Texas
Glenn
 

Hi Sherman, EGO and pride go hand in hand, they can be a motivation to work hard and do good, but some take the other path of self destruction. I've seen both examples many times over the years.

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Sherman Owner
Texas
Sherman
 

You are correct in that there must be a healthy balance….. that being said, let's have a glance at development. I grew up with a boy my age whose Daddy was a star running back for a major college football team. Recruited by the Detroit Lions, Dad never did go to the pros due to pressures germane to both his life situation and the times (mid-50's). Dad was a coach (one of mine as I grew up, as…

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Nelson Diagnostician
North Carolina
Nelson
 

No nvh kit, just the basic way as in the past. Verify correct tire pressures before test drive, quick visual of tires while on the ground. During test drive, steer right/left and listen for noise changes if suspected in front Put on lift. Inspect tires again for condition/wear issues. If tires are suspected, do tire swap and drive again Another method, while on the tire, grasp strut spring…

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Kerry Mobile Technician
Ohio
Kerry
 

Rotate the tires using whatever format you choose. If there's not a significant difference between all four tires in terms of wear, you could just go front to back and back to front. If you think it's in the front and aren't sure if it's a bearing or a tire, criss cross the front to the back so that it will produce the most directional data you can get. On the way to doing that you can always…

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Mark Engineer
Colorado
Mark
 

Darren: You asked: “How do you guys, generally speaking, differentiate between a tire and bearing noise.” I have both the wired and wireless Chassis Ears (depends n the application which I use). Kerry Sutton already answered with what I do, after I have located/pin pointed where the noise is, then I rotate the tires and see if the noise moves (if the noise stays, it is in that rotational…

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Martin Instructor
British Columbia
Martin
 

Hi Darren. An NVH kit or other method of associating tire and wheel RPM with the noise can definitely help. Still, the basics as others have identified can work well. Temporarily inflating a tire to it's maximum listed pressure can change a tire noise, as can rotating tires to different sides and corners of the vehicle. Years ago, my wife's ‘99 Venture van developed a hum in the left rear. I…

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Justin Mechanic
Tennessee
Justin
 

I use the methods that have already been mentioned. Another test I’ve used is an infrared thermometer to measure the temperature of the bearing to see if it is significantly hotter than the others. This will work best after a really long test drive. Sometimes, not always, it helps to consider the frequency of the noise with respect to the diameter a bearing versus a tire. What I mean is, if the…

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Glenn Owner/Technician
Texas
Glenn
 

Hi Justin, I had an interesting one years ago while working at a body shop as a technician. In that position I was responsible for quality control of every vehicle before delivery to the customer. One car that I hold fond memories of is a BMW. All work was completed and I was performing the QC checks. When test driving it, it had an annoying, very slight, slow speed vibration when coming to a…

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Jesse Owner/Technician
Pennsylvania
Jesse
 

HI when i am faced with these situations i look at the tire for wear patterns, next pull rotor and turn wheel bearing by hand , early stage bearing failure is it turns easy , sometimes making noise with load on wheels but not always, second level you can feel the roughness when turning by hand, the same is applied to belt pulleys, hope this helps

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Richard Owner/Technician
Missouri
Richard
 

All solid advice so far but I would like to add one thing, in my experience a tire noise will change tonality on different types of road surface. If you can find and area where the surface transitions from asphalt to concrete you should be able to hear a change in the sound if it's a tire noise but a bearing noise will not.

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Rick Technician
Illinois
Rick
 

Absolutely. That is the simplest thing and a lot of times, the only thing you need to do. Working at a dealership has the added luxury of being able to pull a set of wheels of another vehicle and taking the customer for a ride. Then you get to say, “ told you so”. Well, not always, lol

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Randall Technician
Pennsylvania
Randall
 

Darren, We have all been bit by this dog. I like to observe the sounds on the road test as a starting point. Tire noise TENDS to be noticeable from a dead stop and the intensity increases gradually with speed. Whereas bearing noise TENDS to be noticeable at about 40mph and grows louder with speed. Every case is different! Good luck Randy

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Darren Technician
Wisconsin
Darren Resolution
 

Thanks for all the replies!! You guys gave me some excellent advice!! Thank you.

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Rick Technical Support Specialist
Missouri
Rick
 

Simple test: Works well many times. Grab the spring while rotating the wheel on the lift to feel hub bearing vibration. Works good for left vs right side too.

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Fred Owner/Technician
Maryland
Fred
 

Been using this method for years works 98% of the time or better for us. If you have an NVH put it on the spring, when on the hoist . We have had hundreds wheel bearing failures in this snow zone . I think they are using magnesium chloride, it gets in to everything and corrodes everything.

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Matt Educator
Ohio
Matt
 

First thing I do is test drive on a road that changes pavement type. Tires will change pitch when the road surface changes and bearings won't, generally speaking.

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Scott Owner/Technician
Missouri
Scott
 

Move the tire to a different position. Did the noise move, or change? If so, then it was a tire. I have had perfectly normal looking tire that sounded like a very bad wheel bearing ONLY WHEN TURNING IN ONE DIRECTION. When it was on the other side of the car, it was perfectly quiet. Customer drove the car for many thousand miles with that tire. We had to be careful when rotating the tires to…

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