# Knocking... they say ratcheting timing belt...



## yanstonge (Mar 2, 2014)

Good day everyone,

I have just bought this vehicle, Cruze 2011 1.8L, manual transmission... I've had all sorts of problems, but all repaired under warranty... transmission, heater core, prestone water pump, mirror, back suspension boots reglued, front window punctured, radio replaced due to inop in cold weather... ...

Question: only when the vehicle has warmed up, either giving a good gas pedal shot or declutching to get speed from the first gear, there is a (sounds like) knocking sound... Dealer says it is a ratcheting system on the timing belt that is totally normal... He says not to bring the car in for this, he will not find anything abnormal... Only we have tried to simulate under same conditions, a 2013 car (1.8L, manual transmission, with same guy), it did it (this knocking sound) only once, very slightly compared to mine, over about 100 trials... 

Anyone aware of this knocking sound??

Just so everyone know, it is NOT the antiskid system working as I hear it very often here, I live in Québec, Canada, every morning getting to work, my driveway road is uphill, icy with snow... What I am talking about really sounds as 'knocking', not the antiskid system...

I have not experienced this sound trying to accelerate low gear going up steep, tried on 1st all the way up, also second, third... Believe me, I really tried hard to put it under 'hard working conditions going steep uphill accelerating, low RPM, high RPM... ... no result, no knocking sound...

Could it be loose engine mount(s)????? Can anyone show me where they are????

Thanks... 

Yan


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## NickD (Dec 10, 2011)

My Cruze makes all kinds of weird sounds driving on crunchy snow with frozen clunks of it scattered all over the roads. But quiets down if I can find a clear road.

If from the engine, these knocks should be heard while parked and revving the engine. Like a sticky hydraulic valve lifter. These can come and go.

Also seeing many new pot holes in once good roads, cause by pouring tons of salt on it. On uncleared roads, pot holes in the snow itself. Another hazards is large hunks of ice that felt off other vehicles. This never was a problem when they didn't use salt, but studded snow tires itself. But the idiots blames studded snow tires for all this, wonder if they are getting a kick back from road construction contractors.

How does studded snow tires cause a slab of concrete to rise 2"?


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## spacedout (Dec 7, 2010)

NickD this is off topic but believe it is not the salt that causes the road damage in the winter, but is simply water damage. Say the State/County wants to save some money so decide not to maintain their roads properly in the fall and fill all cracks(usually seen as tar strips). These cracks allow melt water from the road to get under the surface so you end up with either a pot hole or a heaved section of road if it refreezes.


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## NickD (Dec 10, 2011)

Was trying to say, experiencing a lot of knocks in my Cruze primary caused by road conditions to somewhat stay on topic.

A better way of removing snow is using these large rotating brushes in place of a steel plow. But if there is no snow on the roads, would be no water to seep in those cracks. Key around here is to pour tons of salt on the roads, even on a fresh five inchs of snow with no plowing that creates a slush. Just gave up a long time ago to bring this up at city meetings.

But do this in all cities, hopeless.


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## Bullet (Aug 9, 2013)

Hi spacedout, I believe that the salt is still partly quilty as the snow is melting in temperatures above -8 centigrade and not above zero C as normally. Makes much more water into those cracks etc. and when the salted water dilutes, then the water is freezing and breaking everything around.


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## spacedout (Dec 7, 2010)

Bullet said:


> Hi spacedout, I believe that the salt is still partly quilty as the snow is melting in temperatures above -8 centigrade and not above zero C as normally. Makes much more water into those cracks etc. and when the salted water dilutes, then the water is freezing and breaking everything around.


I had thought of this also as normally spring thaw would only cause pot holes, now have melt water happening all winter long with salt, getting under the road surface and refreezing and causing more heaving. 

We have one road locally being called the worst road in the state, its a minefield of pot holes and jump ramp looking heaves. On the local news they were interviewing drivers most were saying you could not go even 35mph down the road this year as bad as it is. Had to laugh as just that day was going 50mph in the cruze down the road and was shocked how well the 16in 1lt tires and non-sport tuned suspension could soak up all the bumps.


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## NickD (Dec 10, 2011)

Well, getting back to the OP, not only does the Cruze not have a ratcheting timing belt, but doesn't have a timing belt period.


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## Bullet (Aug 9, 2013)

Yes, Cruze takes those holes pritty well. I still have different size wheels in winter and in summer, 16 inch wheels in winter and 17 inch in summer. These 16 inch wheels with higher profile (can't remember it better now) tires are a lot better to drive in our roads than those summer tires with lower profile. I just wait those summer tires to wear so that I would have a reason to replace them with higher profile tires. Pity that I did get the 17 inch rims with the car, more difficult to get bigger profile and narrower tires. And as a surprise for me, with these winter tires with stud my fuel consumption is less than with summer tires. Normally with studded tires the fuel consumption is more. Weird.
Anyway, I also hear all kind of sounds from the car, all kind of relays and buzzing sounds but the car is too complicated for me to even try to understand everything.


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## Robby (Mar 1, 2013)

Nick and others,
The OP is asking about about a timing belt noise on a 1.8 Cruze.
This engine does indeed have a timing BELT as opposed to the chain found on the 1.4.

Regardless, to the OP.......Where are you located, and, for the record, a properly adjusted timing belt makes no sound and is designed to be silent.
The camshaft load on the belt does not ever change, it doesn't experience any load changes regardless of throttle position.....WOT or just cruising along, the cam experiences no load changes.....therefore, this supposed sound from the cam or belt is, for all intents, impossible.

The reason for my location question is I don't know what ambient temperature you are operating in and you should be able to tell us if the sound you hear is while the engine is cold or at full operating temperature.....or both.

Rob


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## spacedout (Dec 7, 2010)

NickD said:


> Well, getting back to the OP, not only does the Cruze not have a ratcheting timing belt, but doesn't have a timing belt period.


The OP has a 1.8L cruze not a 1.4T, so they have a timing belt not a chain.


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## jblackburn (Apr 14, 2012)

Most timing belt systems simply have a hydraulic or mechanical tensioner that gradually (extremely slowly) increases pressure on a pulley pressed against the timing belt. 

I wonder if what you're hearing is a dual mass flywheel. They'll make some knocking noises when changing loads on the engine, but does help reduce shift shock and NVH with a small 4 cylinder. For example, when I start my (1.4) Cruze on a hot summer day with a hot motor, there's a bit of knocking for 10-15 seconds that sounds a bit like a diesel motor. 

Have a friend try to duplicate the noises from inside the car while you listen under the hood. 


Sent from AutoGuide.com App


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## NickD (Dec 10, 2011)

Robby said:


> Nick and others,
> The OP is asking about about a timing belt noise on a 1.8 Cruze.
> This engine does indeed have a timing BELT as opposed to the chain found on the 1.4.
> 
> ...


Duh? Skipped that part about this being the 1.8L, ha, send me to my room for a time out. Granddaughter hates this, I love it. My mistake. 

Already had my fill with timing belts.










Says should be changed every 60K and does use an idler pulley as well with another limited lubricated ball bearing that can seize up. Then with an interference engine as well. Read this before buying the Cruze, darn good reason to pay extra for the 1.4L engine.


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## Dale_K (Jul 16, 2011)

I also suspect the dual mass flywheel.


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## yanstonge (Mar 2, 2014)

Robby said:


> Nick and others,
> The OP is asking about about a timing belt noise on a 1.8 Cruze.
> This engine does indeed have a timing BELT as opposed to the chain found on the 1.4.
> 
> ...


Thanks Rob to get back to original message, knocking... for your question, I live in Quebec, Canada, it is winter here now, average temperature outside now is around 14f (funny, I had to use convert program, we use Celcius here, wich was -10 deg C)... ...

This happens only when engine is warmed up, normal operating temperature. As I said, in neural, only when hitting a quick shot on gas pedal (VERY QUICK), AT THE VERY MOMENT THAT I TOUCH the pedal, NOT while raving, BEFORE any engine acceleration. Also happens on normal operation, when releasing clutch (first gear, sometimes also happens in second) when a slightly more than normal acceleration is required (bit more gas pedal also, of course. If releasing clutch very slowly with moderate gas acceleration, for a slow, no stress day acceleration, nothing is heard.

According to what I have read, can someone confirm that I have, for my 2011 Cruze 1.8L, manual, a belt with a tensioner and NOT a chain? Is there a way I can confirm moderately easily, physically on the car? It would put me in confidence when talking about this problem with the garage guy (Chevrolet dealer). At least, I could tell him not to come back with the timing chain ratcheting story...

You guys are on the ball, I am so happy I can discuss such concerns with people who know so much more than me about my own car... I will learn to know it a little more with time, but your help is greatly appreciated... Thanks guys!

Yan


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## jblackburn (Apr 14, 2012)

The 1.8L is 100% a timing BELT engine.

Timing belts should not make noise. The whole point of a timing belt is that it's quiet.

Your symptom should be easy to duplicate if it is produced by a quick stab of the gas pedal, and if my theory of the flywheel is correct, should be coming from the right side of the motor (US drivers side).


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## yanstonge (Mar 2, 2014)

NickD said:


> Duh? Skipped that part about this being the 1.8L, ha, send me to my room for a time out. Granddaughter hates this, I love it. My mistake.
> 
> Already had my fill with timing belts.
> 
> ...


NickD, on your diagram, does the circled 'T' stand for tensioner and 'I' stand for Idler Pulley? If my car is equipped with a belt, not a chain and recommended to be replaced every 60K: the car was sold at 63K, two months ago, still under full warranty for an other month... should I ask a timing belt replacement? 

When buying the vehicle, oil change was due, few klicks overdue... they said recommended oil change was due, oil change was done... if a timing belt change was due, according with their 'recommended' schedule, would it be exaggerating to ask them to replace it? I understand that a timing belt replacement is a (significant) little bit longer than an oil change, but if the idea is to respect 'recommended' limits, would it be sensibly normal that they respect their own schedule selling a used vehicle? Thanks NickD

Yan


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## yanstonge (Mar 2, 2014)

Thanks jblackburn, now, I have a timing belt, not a chain... so the theory of a ratcheting chain goes in file 13... please let me know a little more about this 'dual mass flywheel'... and also what does NVH stand for?

I have never experienced any of these knocking sounds for 10-15 seconds, not even 1 second, except when, as I and you said, there is a quick stab of the gas pedal.

Thanks!

Yan


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## jblackburn (Apr 14, 2012)

yanstonge said:


> Thanks jblackburn, now, I have a timing belt, not a chain... so the theory of a ratcheting chain goes in file 13... please let me know a little more about this 'dual mass flywheel'... and also what does NVH stand for?
> 
> I have never experienced any of these knocking sounds for 10-15 seconds, not even 1 second, except when, as I and you said, there is a quick stab of the gas pedal.
> 
> ...


NVH = noise, vibration, harshness. Something typically inherent with 4 cylinder motors, so manufacturers try to reduce all 3 as much as possible. In my opinion, they have made great strides since the late 90s.

Also, the timing belt change interval for a Cruze 1.8L is 97500 miles. You can have the timing belt area inspected, but it is very rare for any of the bearings, etc to have problems this early on. 

A dual mass flywheel basically has a spinning part connected to the engine, and a separate spinning mass connected to the transmission. In between, a series of springs offers a little "wiggle room" that helps smooth out shift shock and chattering in between gear changes that is unpleasant or could cause damage in the driveline. 

However, sometimes these types of flywheels will make brief knocking noises as they are twisting at different speeds, like when you quickly blip the throttle. 


Sent from AutoGuide.com App


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## NickD (Dec 10, 2011)

Here is the tensioner, has a single set screw for the tension adjustment.










And the idler, see these are made from stamped steel, perhaps a bit more reliable, daughter's Ford used plastic that broke well before the book said to change the belt, engine was history. One key reason have a new Cruze, was cheaper for me to give her my Calvalier and buy a new Cruze than to find her another used up vehicle to drive.










Hmmm, been over five years since I retired, but know back then, all kinds of problems with these Made In China limited lubricated ball bearings seizing up, but will hear than noise at the front of the engine, particular when cold where what grease they use gets rock hard.

Was going by Gates recommendation for changing the belt at 60K. For me, just recently did this job on my 88 Supra, replaced both the idler and tensioner, and made darn sure was Made in Japan, Canada, or the USA bearings. Also popped off the caps, cleaned them up and replaced with Wolf's high temperature red bearing grease. Have a 40 year history with this grease, it does not cake up like some of this new crap.

Its best to buy a component belt kit and replace everything.










In particular with an interference engine, translated into English, means if the timing belt or sheaves breaks, the valves would crash into the pistons causing real major damage.

Also when changing a belt, remove the plugs, and run the starter motor several times to break in the new belt. You may think your tension is correct, but that belt would loosen. A loose belt can fall off, and too tight, can break, has to be just right. 

Changed the belt on my Supra 15,000 miles before it was due, good thing, those bearings were getting very stiff. Toyota would do this for me for only around 3,000 bucks. Can believe this the other stall in my garage was loaded with parts that had to be removed first.


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## Robby (Mar 1, 2013)

To the OP,

Having read your description, specifically the 'Quick Stab' of the throttle inducing the sound, I agree with others as the most likely culprit is the dual mass flywheel.
Some are more suceptible to this than others....along the lines of production tolerances....yours is on the loose side but likely no repair is called for.
The ones where the internal tension springs have failed will rattle at idle, fairly steadily and worse with the A/C compressor running, which applys additional load to the crankshaft.

So far, I think you're OK based solely on your description.

C to f conversion not really necessary as long as we know you are speaking in Celsius.

Rob


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## NickD (Dec 10, 2011)

Well apparently, there is an aftermarket cure for this DMF.

NEW! Chevy Cruze / Sonic performance clutch kits & flywheels | Clutch Masters Blog

For steet use a single steel flywheel is recommended for longer wear. This DMF's remind of these rubber coupled harmonic damper pulleys they started using to cut down some vibration. Find until the rubber disintegrates, the outer hub falls off, and leaves you stranded in some God forsaken place. 

"*A Dual Mass Flywheel (DMF) is a flywheel in two concentric parts or two facing flywheels stuck together with flexible compound to damp down transmitted vibration and gear rattle for the gear box. Many newer model vehicles now come standard with a factory DMF. Many times enthusiast choose to replace a DMF with a SMF and here is why: **** 


DMF’s tend to be more expensive than a SMF.
DMF’s are not designed to be resurfaced like conventional SMF.
DMF’s usually weigh 30+ lbs depending on the application which will cause unwanted turbo lag.
DMF’s cannot withstand a high rate of abuse and may fail under spirited driving."


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## yanstonge (Mar 2, 2014)

NickD said:


> Well apparently, there is an aftermarket cure for this DMF.
> 
> NEW! Chevy Cruze / Sonic performance clutch kits & flywheels | Clutch Masters Blog
> 
> ...


Would you recommend replacing to get rid of 'knocking' like sound+ long lasting?


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## yanstonge (Mar 2, 2014)

NickD said:


> Here is the tensioner, has a single set screw for the tension adjustment.
> 
> 
> 
> ...


NickD, car is only 3 years old, you would recommend replacing it now? Shouldn't I wait a few extra years?


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## yanstonge (Mar 2, 2014)

yanstonge said:


> NickD, car is only 3 years old, you would recommend replacing it now? Shouldn't I wait a few extra years?


Thanks for all this info, VERY interesting... learning from people who know...


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## NickD (Dec 10, 2011)

60K Miles is what Gates recommends, what does your owners manual say on when to change the timing belt?

Previous Japanese cars I have owned were always at 60K miles, Nissans, Toyotas, and Hondas. Just changed the belt in my 88 Supra with 50K miles on it. Glad I did, tension and idler bearings were getting very stiff.

Ha, wonder who came up with the term,"dual mass flywheel"?

Sounds more like to me a "glued flywheel".

Been using solid steel flywheels for over a hundred years now, extremely reliable and can be resurfaced. And exactly how much vibration is being eliminated? Just sounds like more newly created problems, just like that rubber band harmonic balancer is.


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## jblackburn (Apr 14, 2012)

Improved tensioners wear the belts less these days. I changed the belt on a 10-yr-old Camry @ 105K (the recommended interval for that car, btw)...and the belt...and everything in the path still seemed perfectly fine. Same with a Volvo at 6 years and 70K miles (70K was the recommended interval, later changed to 105 with an improved tensioner setup). I always changed all bearings, rollers, etc...but they could have gone longer.

Seriously...don't worry about the timing belt til the change interval is due. Changing every 60K would be a waste of money on a car that's designed for much longer (97,500 miles in the Cruze...or somewhere around 7+ years, whichever comes first).

Drove 2 stick shift models of the same car, a year apart...one had a DMF; the older, a SMF. Being a buzzy 5-cylinder engine, the difference in smoothness was noticeable, if only just. I've heard they're a huge pain to change a clutch on though...but never done one on a dual flywheel myself.


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## NickD (Dec 10, 2011)

Was a weekend job around here trying to drop a transaxle in a FWD vehicle where the splines on the half axles would be rusted in solid to the hub bearings.

Would make my own dowel to center the clutch disk to make darn sure that clutch disk was perfectly centered. Just a fraction of a mm off, would never insert that shaft. Would need two helpers to reinstall the transaxle, extra heavy with the differential and have to be twisted and turned just to get it up there. Plus need a third hand to rotate the shaft so it would slide in.

Also required rear engine top support, with no transaxle holding it up, it will fall. And every possible AC, PS, brake, and wire harness lines were in the way. With a hydraulic clutch, had to learn how to enjoy fluid dripping on your face.

Best tool I have for removing tie rod ends and ball joints is an impact air hammer with a blunt nosed tool. One hit of the trigger and pop right out. Those wedges are a bad joke for teaing up the boots on these things. And can't just buy the boot have to replace the whole darn thing. Plus pay extra for a wheel alignment job.

Not a fun job, Fords are even worse with that stupid subframe design. 

I think about this everytime I release the clutch. Ha, you can call me a grandpa driver whenever you want.


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## harley (Jun 3, 2017)

NickD said:


> Well, getting back to the OP, not only does the Cruze not have a ratcheting timing belt, but doesn't have a timing belt period.


The 1.8 has a timing belt.The 1.4 has a chain.


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