Best 5W-40 or 0W-40 For DI Noise?

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I'm leaning towards a 5W40 or 0W40 for my upcoming oil change on my 2012 CTS 3.6 LFX. I'm currently running 0W30 ESP with about 4k miles on it (going to dump it at 5k). I am looking for an oil that quiets the valvetrain/DI high pressure pump ticking. Of all the oils I have used Redline 5W30 has quieted it more than others but I'm done using boutique oils since I never feel comfortable taking advantage of the long drain intervals that make them cost effective compared to the $30/jug high end offerings at Walmart. I'm thinking of using M1 FS 0W40 or 5W40. What 5W40/0W40 would you run to quiet a motor and also provide protection for high rpm driving? This will be my summer fill so low temperatures are not a concern. I will most likely hit my 5k OCI by fall and then dump it for another round of ESP 0W30 to get me through winter and spring.
 
Is the ticking due to the interaction of the valvetrain, or the hydraulic fuel pressure spikes?

Oil may or may not reduce the former, but it's most likely to do nothing for the later.

Worth a try, but don't get your hopes up.
 
I ran M1 0w-40 for the last OCI before I switched to VRP on my LFX. The DI system is noisy but normal for DI. The oil is not going to mute that at all. It will never be a quiet engine, even will all the sound dampening they have under the hood.

Run the 0w-40 and see what you think. It’s fantastic oil for the price point and the engine runs great with it.
 
My Benz M276.8 engines are notorious for loud DI noise and valvetrain/timing noise.

My experience:

M1 0w40 was VERY noisy.
Castrol 5w40 is much less noisy (compared to M1)
Mobil Racing 15w50: quiet as the grave.

Obviously MR 15w50 is not really suitable for long drain interval, all season use (if you have cold starts and low winter temps).

So I've run Castrol Euro 5w40 for the last few years, no complaints.
 
Is the ticking due to the interaction of the valvetrain, or the hydraulic fuel pressure spikes?

Oil may or may not reduce the former, but it's most likely to do nothing for the later.

Worth a try, but don't get your hopes up.
It is mostly the DI high pressure pump. Port injection 3.6s are much quieter as they don't have the secondary pump and high pressure injectors.
I ran M1 0w-40 for the last OCI before I switched to VRP on my LFX. The DI system is noisy but normal for DI. The oil is not going to mute that at all. It will never be a quiet engine, even will all the sound dampening they have under the hood.

Run the 0w-40 and see what you think. It’s fantastic oil for the price point and the engine runs great with it.
M1 0W40 seems to be highly recommended on here just like ESP. The DI system is indeed noisy but nothing out of the ordinary for a newer vehicle. I miss 20 years ago when engines ran quiet as a mouse. A brand new 3.6 sounds the same as mine so it doesn't seem like something they've cared to mitigate in the last 13 years. I know when they started putting the DI 3.6s in Cadillacs they had to issue service bulletins to not replace any components due to noise and explain to customers that the system is operating as intended and the noises are just a characteristic of the design. I wonder if they're still doing the same for engines locking up on $120k Escalades... operating as designed.
My Benz M276.8 engines are notorious for loud DI noise and valvetrain/timing noise.

My experience:

M1 0w40 was VERY noisy.
Castrol 5w40 is much less noisy (compared to M1)
Mobil Racing 15w50: quiet as the grave.

Obviously MR 15w50 is not really suitable for long drain interval, all season use (if you have cold starts and low winter temps).

So I've run Castrol Euro 5w40 for the last few years, no complaints.
Interesting about 0W40 being noisy. I will look into Castrol 5W40. I don't think I'd ever put something as thick as 15W50 in even during the summer. I think it would cause VVT issues as well as cold start pumpability problems.
 
It is mostly the DI high pressure pump. Port injection 3.6s are much quieter as they don't have the secondary pump and high pressure injectors.

M1 0W40 seems to be highly recommended on here just like ESP. The DI system is indeed noisy but nothing out of the ordinary for a newer vehicle. I miss 20 years ago when engines ran quiet as a mouse. A brand new 3.6 sounds the same as mine so it doesn't seem like something they've cared to mitigate in the last 13 years. I know when they started putting the DI 3.6s in Cadillacs they had to issue service bulletins to not replace any components due to noise and explain to customers that the system is operating as intended and the noises are just a characteristic of the design. I wonder if they're still doing the same for engines locking up on $120k Escalades... operating as designed.

Interesting about 0W40 being noisy. I will look into Castrol 5W40. I don't think I'd ever put something as thick as 15W50 in even during the summer. I think it would cause VVT issues as well as cold start pumpability problems.
While running 15w50 for a short "race season" OCI, I experienced zero issues with VVT (the M276.8 engine has VVT on all 4 cams), the car performed excellently both on track and on the street.

The difference in viscosity between a 5w40 and a 15w50 at 90+ deg ambient starting temps is not even close to the realm of causing any issues.

Castrol Euro 5w40 Cst@100C: 13.3

Mobil 1 15w50 CsT@100C 18.2

It's roughly a 35% increase. Which is about the same as going from a an average 5w30 to a Xw40.

It's not like it's twice or three times as thick.
 
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I mixed one part 15w40 with three and a half parts 5w40 to stop my engine from ticking. After that I simply turned up the radio.
 
I mixed one part 15w40 with three and a half parts 5w40 to stop my engine from ticking. After that I simply turned up the radio.
I don't hear the noise in the car it has plenty of sound insulation. It's when I'm outside the car or in a drive thru with the window down that I hear it. It's just not a noise befitting of a Cadillac. Years ago you couldn't tell when a Cadillac, Audi, Mercedes, BMW was running. Now they're all ticky and clattery like a diesel truck.
 
Quietest oil I've ran is Castrol Euro 5w30 (SL 502, not the K version with SP/504). Not saying I think it's the best, just that it ran quieter than the other oils you've mentioned.
 
Mobil 1 seems to make the engine run quietest to my ear. Ive run many oils and anything that is Mobil 1 seems to run quiet.
 
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I'm leaning towards a 5W40 or 0W40 for my upcoming oil change on my 2012 CTS 3.6 LFX. I'm currently running 0W30 ESP with about 4k miles on it (going to dump it at 5k). I am looking for an oil that quiets the valvetrain/DI high pressure pump ticking. Of all the oils I have used Redline 5W30 has quieted it more than others but I'm done using boutique oils since I never feel comfortable taking advantage of the long drain intervals that make them cost effective compared to the $30/jug high end offerings at Walmart. I'm thinking of using M1 FS 0W40 or 5W40. What 5W40/0W40 would you run to quiet a motor and also provide protection for high rpm driving? This will be my summer fill so low temperatures are not a concern. I will most likely hit my 5k OCI by fall and then dump it for another round of ESP 0W30 to get me through winter and spring.
The ticking is from the solenoid fuel injectors. Viscosity will have limited impact on that noise.
 
It is mostly the DI high pressure pump. Port injection 3.6s are much quieter as they don't have the secondary pump and high pressure injectors.

M1 0W40 seems to be highly recommended on here just like ESP. The DI system is indeed noisy but nothing out of the ordinary for a newer vehicle. I miss 20 years ago when engines ran quiet as a mouse. A brand new 3.6 sounds the same as mine so it doesn't seem like something they've cared to mitigate in the last 13 years. I know when they started putting the DI 3.6s in Cadillacs they had to issue service bulletins to not replace any components due to noise and explain to customers that the system is operating as intended and the noises are just a characteristic of the design. I wonder if they're still doing the same for engines locking up on $120k Escalades... operating as designed.

Interesting about 0W40 being noisy. I will look into Castrol 5W40. I don't think I'd ever put something as thick as 15W50 in even during the summer. I think it would cause VVT issues as well as cold start pumpability problems.
I've been running 15w-50 in my Accent during the summer for years. I can go into the live data and see the CVVT data in real time and I've never seen a commanded vs actual discrepancy or even a delayed response with 15w-50. If you want a quiet engine 15w-50 (the regular m1 version) is quite good. 5w-50 and 0w-40 are quite noisy in my experience. You can definitely reduce the noise from the fuel pump tappet itself with oil, however the ticking injectors are always going to be loud unfortunately.

There is also a benefit with the high temperature full shear viscosity stability you get with a 15w-50 that will lead to better chain and valve train protection over time.
 
Royal Purple 5w-30 ran nice and quiet in my previous vehicle, 1.4 eco tec engine plus it improved the gas mileage. tried Mobil 1 and it was noticeably noisily and seemed to get louder as it sheared down.
 
Colorado v6 is noisy especially when cold. Quiets down once warmed up. Not sure any oil would make a difference. RL is one that comes to mind that anecdotally appears to help quiet some valvetrains.
 
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