Skyactive-G likes Rotella GT 0w20

Status
Not open for further replies.
Joined
Jul 4, 2019
Messages
51
Location
Central Valley, ca
20k miles in 6 months on our ‘19 cx5 non-turbo, and on to another oil. This time was Rotella GT 0w20 courtesy of the AZ clearance. Engine seems to really like this oil and idles butter-smooth, like it did on the Zepro 0w20 Moly. So far here's how I'd rank the oils tried in our Mazda (all 0w20, completely subjective and anecdotal):

1. Idemitsu Zepro High Moly & Rotella GT (tie)
2. Valvoline ME & Mazda factory syn non-moly (tie)
3. Castrol Edge black bottle

Next up in a couple months will be QSUD, also courtesy of Autozone
 
I really struggle to believe you could notice any difference between those three quality oils.

I've gone from extremes in engines and never been able to notice any real difference other than maybe tiny bit less noise from the camshaft areas.
 
I see your point and would tend to agree with you if it weren't my own observations. I guess my statements are based mostly on engine idle smoothness and volume. With the Zepro (on multiple occasions and today for the first time on RGT), I've exited the vehicle without turning off the engine solely because I didn't realize it was still on. This never happened with the other oils bc it seemed that some slight engine noise/vibration was more noticeable. As far as acceleration/mpg/etc, can't really say I noticed much of a difference.

Again anecdotal and subjective...
 
Yeah, I'm not sure it's the oil either.
One thing that I always noticed with our(daughter's) previous 2006 Mazda 3 2.0i was how smooth it idled and reved regardless of oil brand or grade(5w20 or 5w30 dino or syn). Just a nice little powertrain. Mazda builds a nice engine.
 
Last edited:
The Skyactiv 2.0 can be a bit loud on cold starts. Rotella Gas Truck has been gaining a reputation for quieting down engines that are a tad noisy on cold starts.
 
I don't think it's a placebo. I changed out Mobil 1 High Mileage 5w-30 to Shell Rotella Gas Truck 5w-30 in my Mazda 2.3 and it is noticeable quieter and smoother. I can only think differences in base stocks is what makes a difference.
 
Originally Posted by buster
The Skyactiv 2.0 can be a bit loud on cold starts. Rotella Gas Truck has been gaining a reputation for quieting down engines that are a tad noisy on cold starts.




A lot of that noise is the exhaust as it works differently when cold. When it's warmed up the scavenging effect takes hold.
 
Originally Posted by CharlieJ
I don't think it's a placebo. I changed out Mobil 1 High Mileage 5w-30 to Shell Rotella Gas Truck 5w-30 in my Mazda 2.3 and it is noticeable quieter and smoother. I can only think differences in base stocks is what makes a difference.

No, I think it's the add pack. My engines were noisy on M1 too. More so than ST
 
Originally Posted by PimTac

A lot of that noise is the exhaust as it works differently when cold. When it's warmed up the scavenging effect takes hold.


A lot of engines use the VVT on the exhaust to open the valves sooner. It makes more noise and warms the cats faster by pumping hotter exhaust gas out of the engine. Goes to normal after about a minute. My last 3 cars did this. Mazda6, GTI, and Regal with the LTG engine.

The SkyActiv G 2.5 in the Mazda6 was smooth engine from idle to redline. A lot like the Honda K24.
 
That is true. I was referring more to the valve ticking noise in the 2.0. The 2.5L always seemed quieter than the 2.0 for some reason.
21.gif
 
Originally Posted by buster
That is true. I was referring more to the valve ticking noise in the 2.0. The 2.5L always seemed quieter than the 2.0 for some reason.
21.gif






I may be wrong but it's my understanding that the 2.0 and 2.5 are the same engine in every way except for the displacement.

Would that valve ticking be the fuel injection pump?
 
Originally Posted by PimTac
Originally Posted by buster
That is true. I was referring more to the valve ticking noise in the 2.0. The 2.5L always seemed quieter than the 2.0 for some reason.
21.gif






I may be wrong but it's my understanding that the 2.0 and 2.5 are the same engine in every way except for the displacement.

Would that valve ticking be the fuel injection pump?


I believe you are right. That is what I was also told too.

It could be.
 
I was wondering about using RGT with it's decent amount of moly in Skyactive engines. In spite of the "Gas Truck" name, it would seem to be a great oil for that application. I have been using the Idemitsu high moly but my stash of that oil has run out.
I bought 4 jugs of M1 AP 0W-20 (enough for 4 years with the amount of driving we do) for our '17 Mazda 6, but think with the performance and clearance price of RGT I may need to grab 4-8 jugs for that application. I would make a larger purchase, but out of the stable of 3 cars and 3 trucks I maintain, it's the only one that takes 0W-20.
 
Originally Posted by ArrestMeRedZ
I was wondering about using RGT with it's decent amount of moly in Skyactive engines. In spite of the "Gas Truck" name, it would seem to be a great oil for that application. I have been using the Idemitsu high moly but my stash of that oil has run out.
I bought 4 jugs of M1 AP 0W-20 (enough for 4 years with the amount of driving we do) for our '17 Mazda 6, but think with the performance and clearance price of RGT I may need to grab 4-8 jugs for that application. I would make a larger purchase, but out of the stable of 3 cars and 3 trucks I maintain, it's the only one that takes 0W-20.


I'd highly consider it for any 0w20 application as well. It meets SN+/D1/G2 so you're covered.
 
Originally Posted by buster
I'd highly consider it for any 0w20 application as well. It meets SN+/D1/G2 so you're covered.
Except maybe for short break-in fills, Rotella Gas Truck isn't good enough for VW-Audi-Porsche-Mercedes-BMW 0w20 applications. For non-German 0w20 applications, people could upgrade the 0w20 spec they use. More expensive, but at least you know you've got the best in the sump. (I'm assuming the low SAPS 0w20 oils have low enough Ca to avoid LSPI. The Germans haven't said much about that potential issue.)
 
Originally Posted by PimTac
Originally Posted by buster
That is true. I was referring more to the valve ticking noise in the 2.0. The 2.5L always seemed quieter than the 2.0 for some reason.
21.gif






I may be wrong but it's my understanding that the 2.0 and 2.5 are the same engine in every way except for the displacement.

Would that valve ticking be the fuel injection pump?


In that case, how does using RGT oil quiet down the valvetrain? It shouldn't at all for any oil.
 
I posted a thread where my first experience with RGT was the same, and I've always been a naysayer in the past.
 
Status
Not open for further replies.
Back
Top