'16 CX-5 Sport 2.5L drive belt and tensioner replaced

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2016 Mazda CX-5 Sport
I just got my 2016 CX-5 Sport leaking hydraulic tensioner and drive belt replaced at 60,200 miles. It was starting to make squealing belt noise every now and then under slow acceleration. So after the replacement the noise seemed to go away for a few hundred miles.

However, this weekend I heard the noise ever so slightly while make a left turn at an intersection. The mechanic didn't replace the water pump belt. Should the water pump belt be replaced also? Could the water pump belt also be making the noise? The mechanic used Mazda parts.
 
You're not sure what is making the noise?

Tires make a noise sometimes. But I might agree that replacing both belts at the same time would save on labor costs AND you wouldn't be worried about it.

Don't some cars squeal when you crank the steering wheel all the way? Can you reproduce the noise?
 
You're not sure what is making the noise?

Tires make a noise sometimes. But I might agree that replacing both belts at the same time would save on labor costs AND you wouldn't be worried about it.

Don't some cars squeal when you crank the steering wheel all the way? Can you reproduce the noise?
It's the same noise that was starting to occur prior to changing the leaking hydraulic tensioner and drive belt. It seemed to have resolved after they changed it, until very recently.

I am going to drive it around slowly in a quiet parking lot area and see if I can re-create it.
 
⋯ The mechanic didn't replace the water pump belt. Should the water pump belt be replaced also? Could the water pump belt also be making the noise? The mechanic used Mazda parts.
If you had someone else doing the belt replacement, you really should replace the water pump belt at the same time, as the total labor cost would be the same. On the other hand, water pump is just a stretch belt and there’s nothing in between crank pulley and water pump. And the water pump belt usually lasts a lot longer than serpentine belt. I doubt the new squealing noise is from water pump belt, but it’s from new serpentine belt and tensioner may be caused by improper installation or defective tensioner? I’d take the car back to the mechanic and let him figure out where the noise is coming from.
 
You're not sure what is making the noise?

Tires make a noise sometimes. But I might agree that replacing both belts at the same time would save on labor costs AND you wouldn't be worried about it.

Don't some cars squeal when you crank the steering wheel all the way? Can you reproduce the noise?
The squealing with the steering wheel cranked to the limits was due to slipping power steering pump belt. The CX-5 eliminates that by using electric assisted steering, hence no pump (or hoses or steering rack to leak). I will say that I find the steering on the CX-5 to be very good. Don't miss the hydraulics at all.
 
I've driven in some parking garages where my tires squealed the whole time. Must have been the type of pavement I guess.

Some things are a mystery. Until you figure them out😁
 
Watching all the videos about changing belt on the 2.5, I would say it is recommended to change out the water pump belt at the same time because you must remove the accessory belt to get to it which will save you labor. There's no pulley for the water pump belt so you have to muscle your way on/off
 
I've driven in some parking garages where my tires squealed the whole time. Must have been the type of pavement I guess.

Some things are a mystery. Until you figure them out😁
Sorry but I drive on that road very often and I can notice the distinct noise which was the noise I was getting before changing the leaking belt tensioner and belt.
 
There's this stuff you can buy to spray on slipping belts. It doesn't last forever on an old belt but sometimes people might try it to diagnose the belt. I guess the question might be whether you can reach the belt with the spray.

I wonder if you open the hood and then have someone press the gas while you listen. Maybe you can hear where the noise is coming from.
 
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I have 100,200 miles on my 2016 Mazda cx-5 GT 2.5l still has the stock belt tensioner and belt. Surprise the tensioner and belt went out on such low mileage for you.
 
I have 100,200 miles on my 2016 Mazda cx-5 GT 2.5l still has the stock belt tensioner and belt. Surprise the tensioner and belt went out on such low mileage for you.
Shouldn’t be surprised. Actually I was surprised your belt tensioner doesn’t leak at 100,200 miles. Many belt tensioner went at as low as 30K miles including mine at 42K miles. There’s a TSB for leaky belt tensioner and there’re at least 5 revisions for the tensioner. You may not hear any squealing noise when the belt tensioner is leaking.
 
Shouldn’t be surprised. Actually I was surprised your belt tensioner doesn’t leak at 100,200 miles. Many belt tensioner went at as low as 30K miles including mine at 42K miles. There’s a TSB for leaky belt tensioner and there’re at least 5 revisions for the tensioner. You may not hear any squealing noise when the belt tensioner is leaking.
The tensioner on my Cx-5 was probably started leaking around 35 to 40k, if I remember correctly..
 
I have 100,200 miles on my 2016 Mazda cx-5 GT 2.5l still has the stock belt tensioner and belt. Surprise the tensioner and belt went out on such low mileage for you.
As yrwei52 said above, it's a well known and documented problem with many revisions of the tensioner. Mine was leaking at 29,000 miles and I recall the dealer service department state that they see a lot of them leak at around 40,000 miles. It wasn't a covered item under the 5yr/60k powertrain warranty and I was past the 3/36 warranty, so no help from Mazda.
Even if your tensioner isn't leaking, what is the condition of the belts at 102,000 miles? My "old school" habits would have me replacing them just because they've been on long enough.
 
As yrwei52 said above, it's a well known and documented problem with many revisions of the tensioner. Mine was leaking at 29,000 miles and I recall the dealer service department state that they see a lot of them leak at around 40,000 miles. It wasn't a covered item under the 5yr/60k powertrain warranty and I was past the 3/36 warranty, so no help from Mazda.
Even if your tensioner isn't leaking, what is the condition of the belts at 102,000 miles? My "old school" habits would have me replacing them just because they've been on long enough.
Oh woow I didn't know, my mom has 2013 Mazda cx-5 with the 2.0L engine she has 140,000 miles on hers since brand new, the only problem was a mass air flow sensor and that's it, tires, brakes and that's it, transmission fluid never changed but still shifts like brand new. Maybe because of her driving habits, why the SUV hasn't give much issues. Still stock belt and belt tensioner on hers.

To be fair I got my 2016 CX-5 GT at 60k miles, I have a full log of the services done too it from the dealership from brand new till I got it. I see it got a throttle body cleaning, regular oil changes, tires, brakes but no mention of belt and belt tensioner, I inspected the belt and belt tensioner and all looks good. I will definitely keep a look out for sure.
 
⋯ I inspected the belt and belt tensioner and all looks good. I will definitely keep a look out for sure.
There’s very little thick oil in the belt tensioner. If your tensioner looks wet like mine at 41,150 miles, it’s leaking:

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If the rib side of serpentine belt has cracks, it’s about time to be replaced. And at 100,200 miles, certainly it’s about time.
 
Check your tire pressures, low pressures could cause tire squeal on turns.
 
I inspected my one I tried taking a picture but it's a tricky area to put a camera in. My one is dirty but it doesn't have baked on, thick dirt like your. It's not leaking, belts look perfect too.
 
I inspected my one I tried taking a picture but it's a tricky area to put a camera in. My one is dirty but it doesn't have baked on, thick dirt like your. It's not leaking, belts look perfect too.
If your belt tensioner looks clean and dry, it’s fine. If the serpentine belt doesn’t show any cracks on the rib side when you bend it, it’s fine too.
 
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