0w20 or 5w20

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Mazda CX5 2014 GT
I am wondering for summer I should switch to 5w20 instead of 0w20. I think that will also help to reduce the lifter noise...thoughts???
 
Correct me if Im wrong, but both of those have the same viscosity when hot.

Unless your car is consuming oil, I dont see a need for a higher weight.
 
OK, so I had an oil change today done at a new (to me) dealership, and I requested 0W30 instead of 0W20.
They discussed it briefly, and said that it wasn't a problem. I've always though that this 0W20 was a little thin, although I have nothing to back that statement up with.
Anyway, given that the rest of the Mazda world uses 5W30 in this engine, I wanted to try this grade (0w30) to see if it makes any difference.
Hard to tell on the way home, but it seemed to me the car sounded and felt a little happier.
It's probably just my imagination, so I'll see how it runs and feels this summer.
I still remember GJ-Molester a few years ago on here, and his rants about oil grades and how he swore that his car was better off with 5W30 in it.
I may try that next.

Side note:
I asked this dealer for their opinion on my rusting rear rotors, and was surprised at the response. Two other dealers I consulted wanted to replace everything right away, at my cost of course.
These guys said yes, the rotors are rusting, but there's still lots of pad left, and they are wearing evenly, and they still work, so just continue to run them for now until they get worn down enough to need replacing....then do a full rear brake job.
Man, what a refreshing attitude.
 
Recent oil change, and figured out my dealership used 5W-20, despite my engine filler cover saying 0W-20. The work order indicates that semisynthetic was used, so must be a cost savings move. Would prefer a full synthetic.
 
The 0W rating is for cold starts measured at 0F. The 20 rating is for hot running; measured at 212F. The engine is water cooled and has a water to engine oil cooler. Just how much difference would summer temps make to a system that runs at 188F all year long?
 
0w20 or 5w30 are acceptable to use per the manual. I don't see a point in using 5w20.

I'm giving 5w30 a try for this summer.


The environment where I live is a bit severe so I use a 5w30.

I wonder what brand of 0w30 they have at a dealer?
 
Forgot to ask what brand the 0w30 was.
My invoice says Mazda 0000-23-0w30-LT synth 0w30.

One thing I noticed yesterday right away was that the engine didn't clatter as much.
I noticed lately that the engine was getting noisier, and on some mornings sounded like a diesel.
I drive it very little, and only on short trips. Makes me think maybe I had some oil dilution thing going on (like Honda) and that my old oil was really thin. I should have kept a sample for analysis. Oh well, maybe next time.
 
Mine also was getting noisy with 0w-20. Went to Idemitsu 5w-30 and it's a lot quieter and the engine likes it. It even feels like the engine 'pulls ' better. The 2 prior changes were Castrol Edge 0w-20 which turned almost black at 2500-3000 miles and seemed like it thinned out. The Idemitsu is looking better at 2000 miles so far. I don't know what it is with Castrol oils, but I've tried them occasionally throughout the years and never stayed with them even though they are supposed to be good oils.
 
Mine also was getting noisy with 0w-20. Went to Idemitsu 5w-30 and it's a lot quieter and the engine likes it. It even feels like the engine 'pulls ' better. The 2 prior changes were Castrol Edge 0w-20 which turned almost black at 2500-3000 miles and seemed like it thinned out. The Idemitsu is looking better at 2000 miles so far. I don't know what it is with Castrol oils, but I've tried them occasionally throughout the years and never stayed with them even though they are supposed to be good oils.
I've had good reports with Castrol Edge 0w20. But I started using Pennzoil Platinum 5w30. It's been a while since I sent in any samples for reports (do have the samples though), so will have to see how the Pennzoil is doing.
 
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I am wondering for summer I should switch to 5w20 instead of 0w20. I think that will also help to reduce the lifter noise...thoughts???
No, if you really want to reduce the valve lifter noise, you should use 5W-30 oil. Switching to 5W-20 from 0W-20 won’t make any difference for normal engine running temperature.
 
OK, so I had an oil change today done at a new (to me) dealership, and I requested 0W30 instead of 0W20.
They discussed it briefly, and said that it wasn't a problem. I've always though that this 0W20 was a little thin, although I have nothing to back that statement up with.
Anyway, given that the rest of the Mazda world uses 5W30 in this engine, I wanted to try this grade (0w30) to see if it makes any difference.
Hard to tell on the way home, but it seemed to me the car sounded and felt a little happier.
It's probably just my imagination, so I'll see how it runs and feels this summer.
Running 0W-30 or 5W-30 actually is also recommended for SkyActiv-G 2.5L by Mazda worldwide other than North America.

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I still remember GJ-Molester a few years ago on here, and his rants about oil grades and how he swore that his car was better off with 5W30 in it.
I may try that next.
Yes, I did agree with GJ-Molester’s point at the time that by using the 5W-30 our SkyActiv-G 2.5L will be quieter (and may be even better off with 5W-30).
 
Somehow I got 5W20 which is not a recommended oil. Would not think I would get a 'Close enough' solution from a dealership. Have not made a final decision, but thinking I will bring it to an independent shop for the next service visit.
 
Somehow I got 5W20 which is not a recommended oil. Would not think I would get a 'Close enough' solution from a dealership. Have not made a final decision, but thinking I will bring it to an independent shop for the next service visit.
What year/model do you have? Where are you located? Current 2.5s use 5W30 oil…haven’t seen 5W20….
 
Yes, I did agree with GJ-Molester’s point at the time that by using the 5W-30 our SkyActiv-G 2.5L will be quieter (and may be even better off with 5W-30).
5w30 is at least in spec with Mazda recommendations. His problem was that he was recommending even thicker oil like 5w40 which is not.

For me, I kinda like the idea of 0w20 for winter and 5w30 for my oil change going into the summer.
 
5w30.. less blow means less consumption and less valve buildup (even though valve cleaner should be part of every oil change)
 
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