2014 Buick Verano T, 7600 miles, M1 5w30

[A_Harman]

First oil analysis I've done on my recently purchased Buick Verano T.
LHU 2.0L 4-cylinder turbo, direct injected.

BIG problem with fuel dilution:

More than 5% fuel dilution is huge. The viscosity has broken out of 30-weight and is in the low 20-weight range. Gotta do something.
Put M1 High Mileage 5w30 in it at the oil change. I don't expect it will hold viscosity any better.
The fuel economy has been dropping through the winter. I was getting 30-31 mpg when I first got the car, and it has progressively crept down to 27-28 mpg.
I added STP injector cleaner at a fuel fill weekend before last, and the engine had some hesitations the first couple of days, then smoothed out.
Mileage has improved during the last two tank-fulls, now running 30-32 mpg. Maybe it had clogged injectors and fuel treatments during the OCI may help fuel dilution.
Will shorten the next OCI to 4-5000 miles and sample again.

 

[JavierH19]

7600 miles and the tbn was 3.21. That's not too bad. The cleaner probably did nothing. All cars naturally have worse mpg in the winter and that's not too much of a drop.

If it were my engine I'd probably explore 10w-40 like a syn blend instead of a more expensive syn and just change it more frequently like at 5k since it looks more short tripped. Outside of the US like in Mexico and south america gm products with these new turbo gdi's have oil charts from 5w-30 to 20w-50. And yours is off the warranty so bump up if you want. I don't think I'd bother with a full syn 40 grade, they're like $26+ a jug. A cheaper syn blend that's $17 a jug being changed more frequently instead like at 5k is fine.

 

[A_Harman]

I didn't use the injector cleaner until after the oil change, so its effect won't be known until the next sample.
The car is definitely not a short tripper. My round-trip commute is 136 miles.

 

[addyguy]

I know it is repetitive, but I’d try M1 0W-40. Seems to be a good fit with GM high-performance engines.

 

[FZ1]

First oil analysis I've done on my recently purchased Buick Verano T.
LHU 2.0L 4-cylinder turbo, direct injected.

BIG problem with fuel dilution:

View attachment 97832

More than 5% fuel dilution is huge. The viscosity has broken out of 30-weight and is in the low 20-weight range. Gotta do something.
Put M1 High Mileage 5w30 in it at the oil change. I don't expect it will hold viscosity any better.
The fuel economy has been dropping through the winter. I was getting 30-31 mpg when I first got the car, and it has progressively crept down to 27-28 mpg.
I added STP injector cleaner at a fuel fill weekend before last, and the engine had some hesitations the first couple of days, then smoothed out.
Mileage has improved during the last two tank-fulls, now running 30-32 mpg. Maybe it had clogged injectors and fuel treatments during the OCI may help fuel dilution.
Will shorten the next OCI to 4-5000 miles and sample again.

Good, practical, move to shorten the oci to 5k.

 

[Brons2]

I know it is repetitive, but I’d try M1 0W-40. Seems to be a good fit with GM high-performance engines.

This. M1 0w40 is barely into the 40 range, and will shear back to a 30 in usage. Considering it's a turbo DI you may want to do M1 ESP 0w40.