I just purchased a 2015 GMC Sierra. The truck calls for a 0-20 semi synthetic. Should I continue to run the semi synthetic or convert to a full synthetic? I also have PP 5-30 in the garage from my old truck. If I convert to full synthetic would it be ok to use up the 5-30 in the new truck? My guess is the 5-30 synthetic will have similar properties at startup compared to the 0-20 semi synthetic. Thank you for your input.
Semi synthetic or full synthetic
- Thread starter geissjr
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I vote for using the 0W20 synthetic blend, as prescribed by the owner manual. I'm big on following manufacturer recommendations, though.
Follow the mfg recommendation through warranty. But, unless you're in the mountains of California I don't see any need for a 0w over a 5w. That mfg recommendation is for the entire US....so it's an average that will work for all conditions. Just because it works through the warranty period doesn't mean it's ideal for all environments.
Here's a previous post on the subject. There are plenty more around here.
Here's a previous post on the subject. There are plenty more around here.
If I read it correctly, part of the OP was questioning about using full synthetic or semi-synthetic 0W20. I am curious about off the shelf semi-synthetic dexos approved 0W20 oils.
Doesn't seem like there are many options.
Doesn't seem like there are many options.
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Probably from GM if they have a semi syn
Going full syn Xw20 you will be fine. 5w30 full syn you will be fine as well.
Congrats on the new truck. You should have 4 free oil changes over a two year period.
After that a semi or full synthetic that meets the Dexos 1 spec will be OK.
After that a semi or full synthetic that meets the Dexos 1 spec will be OK.
Thank you to everyone for their input.
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I do look for the Dexos approved oils because it is a higher level specification being met. No its not mb 229.5 or BMW LL-04 but it is a very solid spec. I agree with loneranger in using what the manual calls for while under warranty. For the price of eggs I would run a 0w20 if its warrantied for a 20 operating viscosity. The 0w20s seem to have a better mix of group 4/5 synthetics. The viscosity indexes are a fair amount higher than the 5w20s which would seem to indicate the 0w20s have a higher percentage of full synthetics. As a side note.. If you can buy the Dexos oil that is made for GM at a good price... It's a very good oil made by Exxon Mobil. Check out the results from the PQIA. The NOACK on this Synthetic blend is less than 8 which is rather impressive.
The GM dexos1 5w30 that was spec'd for my (sold) Chevy Cruze was also a semi-syn.....most BITOGers were running full syn. in those 1.4 turbos and the UOAs showed that to be a wise choice.
I'd run full syn. 0w20 and forget the semi-syn....in your case I'd use PP and substitute 1 quart of your leftover 5w30 PP at each oil change until you use it up...the Pennzoil syns. are great oils as is M1 AFE...
I'd run full syn. 0w20 and forget the semi-syn....in your case I'd use PP and substitute 1 quart of your leftover 5w30 PP at each oil change until you use it up...the Pennzoil syns. are great oils as is M1 AFE...
You're going to have a hard time finding a 0W-20 synthetic blend off the shelf at any store, I've never seen 0W-20 in anything but full synthetic. I'm sure the dealer has a 0W-20 blend though, if that's where you're going to get it serviced.
DO NOT use the Pennz. Platinum 5W-30. You should stick to the manufacturer's recommendation of 0W-20 until your warranty is gone, at least. 5W-30 won't hurt a thing, but you better follow everything by the book for warranty purposes, in case you need the warranty for anything.
DO NOT use the Pennz. Platinum 5W-30. You should stick to the manufacturer's recommendation of 0W-20 until your warranty is gone, at least. 5W-30 won't hurt a thing, but you better follow everything by the book for warranty purposes, in case you need the warranty for anything.
What is the engine in your truck?
Originally Posted By: tig1
Why would anyone use a semi-syn 0-20 when so many full syn 0-20s are available? Cost? In a $30-$50K truck.
Because engine manufacturers know that conventional oils have a benefit not found in straight synthetics. But bottom line is, no matter the oil, if it meets what the manufacturer calls for your good to go, all apples, just different flavors.
Why would anyone use a semi-syn 0-20 when so many full syn 0-20s are available? Cost? In a $30-$50K truck.
Because engine manufacturers know that conventional oils have a benefit not found in straight synthetics. But bottom line is, no matter the oil, if it meets what the manufacturer calls for your good to go, all apples, just different flavors.
Originally Posted By: NH73
Use the PP 5-30 for your lawn mower or other outdoor power equipment, if you need a place to use it up.
What a waste.
Use the PP 5-30 for your lawn mower or other outdoor power equipment, if you need a place to use it up.
What a waste.
His truck probably has the 5.3 v-8
Originally Posted By: geissjr
I just purchased a 2015 GMC Sierra. The truck calls for a 0-20 semi synthetic. Should I continue to run the semi synthetic or convert to a full synthetic? I also have PP 5-30 in the garage from my old truck. If I convert to full synthetic would it be ok to use up the 5-30 in the new truck? My guess is the 5-30 synthetic will have similar properties at startup compared to the 0-20 semi synthetic. Thank you for your input.
I dont see any requirement for semi syn in the 2015 owners manual, just a mention of Dexos.
From page 10-11
"Viscosity Grade
Use SAE 0W-20 viscosity grade for
the 5.3L and 6.2L V8 engines. Use
SAE 5W-30 viscosity grade for the
4.3L V6, and 6.0L V8 engines.
Cold Temperature Operation: In an
area of extreme cold, where the
temperature falls below −29 °C
(−20 °F), an SAE 0W-30 oil may be
used in the 4.3L or 6.0L engine. An
oil of this viscosity grade will provide
easier cold starting for the engine at
extremely low temperatures."
From page 11-12
"Engine Oil Use only engine oil meeting the dexos1™ specification of the proper SAE
viscosity grade. Look for the dexos1 approved logo for GM approved
engine oil. See Engine Oil on page 10-11."
Source...
Click here for 2015 GM Owners Manual
I just purchased a 2015 GMC Sierra. The truck calls for a 0-20 semi synthetic. Should I continue to run the semi synthetic or convert to a full synthetic? I also have PP 5-30 in the garage from my old truck. If I convert to full synthetic would it be ok to use up the 5-30 in the new truck? My guess is the 5-30 synthetic will have similar properties at startup compared to the 0-20 semi synthetic. Thank you for your input.
I dont see any requirement for semi syn in the 2015 owners manual, just a mention of Dexos.
From page 10-11
"Viscosity Grade
Use SAE 0W-20 viscosity grade for
the 5.3L and 6.2L V8 engines. Use
SAE 5W-30 viscosity grade for the
4.3L V6, and 6.0L V8 engines.
Cold Temperature Operation: In an
area of extreme cold, where the
temperature falls below −29 °C
(−20 °F), an SAE 0W-30 oil may be
used in the 4.3L or 6.0L engine. An
oil of this viscosity grade will provide
easier cold starting for the engine at
extremely low temperatures."
From page 11-12
"Engine Oil Use only engine oil meeting the dexos1™ specification of the proper SAE
viscosity grade. Look for the dexos1 approved logo for GM approved
engine oil. See Engine Oil on page 10-11."
Source...
Click here for 2015 GM Owners Manual
i would choose a full syn 0w20 oil and run it the full OLM. my 2015 malibu says to run any oil which is dexos1 approved. the cap says 5w20 but the owners manuel says 0w20 can be used as an alternative. i plan on useing 0w20 in the winter and 5w20 in the summer.
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