New Owner - New Problem

S

Strings

Member
:
Mazda CX 5 Touring
Just brought home wife's new, 2016.5 CX 5 Touring and she loves it. Traded her 2005 6s GT. So, while out driving it around last nite we find there is an interesting (in that it's gonna be hard to describe) "pulsing" as you slow and stop. It would put you in mind of a tire having bump on its tread.

But it's clearly not a tire.

So, I took the car out of gear and tested for repeatability - it did repeat.

My first guess - and the same as the service writer I spoke to, was that this NOS unit may have developed rust on a brake rotor and maybe it would just wear away > issue would go away.

But the "pulsing" is so uniform in behavior, I'm starting to think it may be a wheel hub or bearing reacting to the mechanical influences of braking.

Familiar to anyone?

BTW, newbie here. This is our 3rd Mazda since our 1983 LTD Edition RX7, the 6S GT mentioned above and of course this CX 5. Guess we're as dedicated to the brand as to the culture.
 
I had an issue that sounds exactly as you describe with the Jeep I had before seeing the light and buying my 2016.5 Touring. :) In that case, it WAS the tire, but it was that the tire had a very slight flat spot from having sat in the same place. When I replaced tires, it went away.

I also had a warped rotor on the Jeep that caused its own problems, but you might consider that it is the tire that's defective.
 
Laurel said:
I had an issue that sounds exactly as you describe with the Jeep I had before seeing the light and buying my 2016.5 Touring. :) In that case, it WAS the tire, but it was that the tire had a very slight flat spot from having sat in the same place. When I replaced tires, it went away.

I also had a warped rotor on the Jeep that caused its own problems, but you might consider that it is the tire that's defective.
Click to expand...

Good way to teat this theory is to move the "problem tire" from front to back...or back to front then test it.
 
Your OP sounds as if this happens when braking ... true?

What happens if you just coast down?

You see, if it's the tire, I'd think you could feel something when coasting. A flat-spotted tire will make a rotational-speed-related sensation. If it happens while braking, I'd be more inclined to think "rotors".

How many miles were on it when you got it?

Google "bedding in brakes". Very few ppl do this, but you could try it. Also Google "warped rotors" so you'll know what this euphemism actually is if they pull it on you.

Otherwise, get it to the dealer right away, or they'll claim you left-foot brake, or ride the brakes, or drove hot brakes through a puddle ... you know, somehow are at fault.
 
Last edited:
I had a new 16 CX5 Touring with 30 miles on on the ODO - never had to bed in any brakes etc. Like phil said - if it happens when you dont brake and just coast - could be rocks in tires or a flat spot or something other than brakes.
Also keep an eye on mpg too.
 
I would recommend bringing to the dealer and let them deal with sorting out the pulsing headache.

Even if they return vehicle to you unfixed, you will have early documentation of the issue in the event it does not go away, and future resolution is needed.
 
Second bedding in the brakes. Brake pad material bonds to the rotor, and if you don't bed-in, or do it improperly, you can get varying thicknesses.

I make 5 passes from 60 mph to 10, medium-hard braking. Then a LONG cool-down drive without using the brakes (15 minutes).
 
Thanks for the replies. I have "coasted" to a stop without the problem occurring as well as braking to a stop with the transmission in neutral where the problem did repeat.

The dealer's service writer did suggest I drive the car for some period of time and that if it was the brakes, it may go away, otherwise, bring it in and we'll inspect and clean the rotors.

So. I'll give it a few days. The pulsing is so linear that it has to be something related to the brakes or the braking effect on something beyond the brakes like a wheel bearing. With so many "votes" for brakes, I'm gaining confident that may resolve the problem.

And Mazdadude! 23 Mazdas! Holy smokes! I kneel to the Dude! Salute!

Thanks again to all.
 
Okay. Took CX5 to dealer thus morning and they "scrubbed" the surface of all rotors and the pulsing has stopped. Service writer believed that the cars had sat for months (2016.5), rust had built up on the brake surfaces, and now all is well.

Well, the pulsing is gone, but there is still the sound of pad vs. rotor friction noise happening. I assume driving the car for a bit longer will take care of that ...

Hope so. Car is so good otherwise - wife's happy. Phones are sync'd. Life is good.

Thanks again.
 
Strings said:
Okay. Took CX5 to dealer thus morning and they "scrubbed" the surface of all rotors and the pulsing has stopped. Service writer believed that the cars had sat for months (2016.5), rust had built up on the brake surfaces, and now all is well.

Well, the pulsing is gone, but there is still the sound of pad vs. rotor friction noise happening. I assume driving the car for a bit longer will take care of that ...

Hope so. Car is so good otherwise - wife's happy. Phones are sync'd. Life is good.

Thanks again.
Click to expand...

Good news that it seems to be sorted. Yes, allow some time for the pads and rotors to wear into each other.

I had a similar problem with my MY2016. Mine turned out to be an issue with the electronic park brake control unit - there was a technical service bulletin about it - the park brake was not releasing properly and we had a sound very similar to what youve described - like a rear brake disc not round.

Took our dealer some time to figure it out, but the EPB control unit was replaced under warranty and the problem was gone and has not recurred.

There was an upgrade to the EPB control unit that fixed the problem in later build cars.

So if it comes back, remind them that there is a TSB about the issue, and ask them to check if your cars ViN comes into the range covered by the TSB on this issue.

Edit:

See post #13 on the thread below for a link to the TSB, you can check if your VIN is included:

https://www.mazdas247.com/forum/sho...and-Electronic-Parking-Brake-Service-Bulletin
 
Last edited:
Kaps said:
Mazdadude's signature takes up more real estate than his posts.
Click to expand...

Ugh, I know, I guess I better change that to... "Had a lot of Mazda's" (rockon)

I think that the car might just need a week or two of use and the pulsing should go away. If you still notice anything after the end of the 600-700 mile break in period, then I would return to the dealer.

Welcome to the club!
 
Last edited:
Please log in or register to reply here.

Similar threads

L
    • Like
New CX-5 Owner!
Replies
2
Views
1K
Pitter
Pitter
R
  • Question
What to expect at 100K miles? 2013 CX-5
2
Replies
28
Views
4K
AL Cx5
A
B
Considering a new CX-5
Replies
7
Views
2K
Martyd
M

Latest posts

Back