[Rodstar43]

While cruising slow between 30 & 40 mph and while increasing the speed very slightly, I hear a low Rumbling sound (like going over the road rumble strips) coming from the engine coompartment. It does NOT always give off that sound. It seemed random but, it is hapening more and more now. This sound does not hender performace if you mash harder on the gas pedal. At idle the noise is not there. If I put the boost performace on the screen, I do not see any thing unusual. What is the car doing? Worried in New Mexico.

2021 CT5 350T with run flat tires

 

[Submariner409]

Tire getting ready to shed some tread ???

 

[Hcdoc60]

I've had the same thing for some time, took the Chevy mechanic on a ride, to demonstrate it. They heard it, but haven't had the time to work on it. It's been going on for months.

I think it occurs when the car is warm. I think it's coming from the rear. My brother suggested a pump is running to pump up the shocks/suspension? IDK if it has that kind of feature.

It's an annoyance, at most.

 

[Hcdoc60]

I think it sounds like a semitruck's Jake Brake. Only softer.

 

[Rodstar43]

While cruising slow between 30 & 40 mph and while increasing the speed very slightly, I hear a low Rumbling sound (like going over the road rumble strips) coming from the engine coompartment. It does NOT always give off that sound. It seemed random but, it is hapening more and more now. This sound does not hender performace if you mash harder on the gas pedal. At idle the noise is not there. If I put the boost performace on the screen, I do not see any thing unusual. What is the car doing? Worried in New Mexico.

2021 CT5 350T with run flat tires

Tires are very good. Less than 8,000 miles are on the odometer. Noise started around 3 to 4 thousand miles ago. Overall performace is good.

 

[rsmithjr222]

It s the run flats IMHO.....Thats why I hate them

 

[Hcdoc60]

It s the run flats IMHO.....Thats why I hate them

Then why would it be at a certain speed, for 10 sec at a time?

 

[Heretolearn]

I have the same issue with mines sounds like it. It happens at certain speeds starting at 30 mph. GM told the dealership it is normal, but I don’t feel that way.

 

[Cadillac Customer Service]

While cruising slow between 30 & 40 mph and while increasing the speed very slightly, I hear a low Rumbling sound (like going over the road rumble strips) coming from the engine coompartment. It does NOT always give off that sound. It seemed random but, it is hapening more and more now. This sound does not hender performace if you mash harder on the gas pedal. At idle the noise is not there. If I put the boost performace on the screen, I do not see any thing unusual. What is the car doing? Worried in New Mexico.

2021 CT5 350T with run flat tires

This is certainly not what we like to hear, Rodstar43. Please know, customer satisfaction is extremely important to us. Our team would be more than happy to take a closer look into the concerns with your 2021 CT5 350T. To do so, please send an email to [email protected] with ATTN: Rodstar43/Cadillac Forums in the subject line.

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[rosalieB1]

I have the same problem/concern with my new 2021 CT-5 it’s currently AT Cadillac service and they’ve had the car since Oct 18 and can’t identify WHERE it’s coming from and also CAN’T give me an estimate on how long it will take them. Very disheartening.

 

[Hcdoc60]

Tire getting ready to shed some tread ???

No.

 

[Hcdoc60]

I have the same problem/concern with my new 2021 CT-5 it’s currently AT Cadillac service and they’ve had the car since Oct 18 and can’t identify WHERE it’s coming from and also CAN’T give me an estimate on how long it will take them. Very disheartening.

I have the same problem/concern with my new 2021 CT-5 it’s currently AT Cadillac service and they’ve had the car since Oct 18 and can’t identify WHERE it’s coming from and also CAN’T give me an estimate on how long it will take them. Very disheartening.

In their defense, intermittent problems are some of the hardest to diagnose.

 

[Sindorei]

Nothing like that happened to my car. However, when the speed is over 60 mph, continue to step on the accelerator, there will be a similar sound as you describe.

 

[nstar]

In their defense, intermittent problems are some of the hardest to diagnose.

When you feel Shutter ,vibration have you looked at tach to see if it is holding steady or having a small jumping going on?

 

[NorthernSRX]

I have the same problem/concern with my new 2021 CT-5 it’s currently AT Cadillac service and they’ve had the car since Oct 18 and can’t identify WHERE it’s coming from and also CAN’T give me an estimate on how long it will take them. Very disheartening.

Is your engine also the 2.0T? Do you feel any vibration when you hear the sound?

 

[CZ4]

Not sure if this is the same issue.

My car is a 2021 CT5-V Awd (non-blackwing). When I have the steering wheel fully turned left, I get a grinding sound from the front passenger side, with the car moving at any speed, somewhat of a rumbling sound. It almost sounds like the tire rubbing against something. However it’s riding on stock 19 wheel/tires. I also took it to the dealer and the only thing they came back to me after 1 day is someone at the dealer has the exact same car and has the same issue.

Dealer said they raised a case with GM, but I haven’t heard anything back.

anyone have a similar issue?

 

[DaMaine1]

I think I'm having this same issue with my 2021 CT5V AWD (non-blackwing). I took it in and did a drive with the service tech who diagnosed the problem as cupping in the tires due to needing an alignment. Alignment was done, tires were rotated and balanced. You would think that the noise would have moved to the rear of the vehicle with the rotation but it didn't. I still hear a rumbling noise coming from the front center point of the vehicle. I did some digging and found a TSB from May 2022 which seems to describe my issue. I've haven't had the opportunity to take it back in but will do so soon. Maybe this is the problem for you as well.

 

[Hcdoc60]

When you feel Shutter ,vibration have you looked at tach to see if it is holding steady or having a small jumping going on?

Tachometer is steady