DEXOS synthetic vs Conventional oil

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My 2012 Sierra 5.3 is past warranty. I've used DEXOS oil for every oil change. I now have 113000 km on the truck. I changed the oil when the dash reminder told me to on the driver information center. This has tun 14000 km on a couple instances, and that alarms me.

My new job gives me access to free mobil conventional oil. I've been using purolator filters for the past 2 years, wix prior to that.

Can I switch over to non synthetic and make my oil change interval 5000 km? It'd simplify things a lot for me.
 
In my original post I said the truck went 14000 km between oil changes. It was still showing 24% oil life at 14000 km, and I started having oil pressure issues. A fresh oil and filter change fixed it up and I haven't had any issues since. I put a sticker on my windshield to change it at 7500 km since that happened.
 
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To meet GM’s dexos spec requires at least a synthetic blend and one supposes GM did this for a reason. And the oil life monitor is calibrated for at least a syn blend. Maybe there wouldn’t be short term damage from using a conventional oil but if you do so you may want to shorten the OCI a bit. Personally, I’d stick with the dexos spec.
 
I think most dealerships use conventional oil in many instances and many Silveradoes still are out there going strong. I wouldn't worry but I would not go over 6,000 kilometers with the oil
 
I was also thinking that. Plus, the 5w30 here is GF-5 and SN rated. Same as the dexos 5w30 I was using all along. I don't think it would be an issue.
 
Dexos spec ain't all that. You just want a good oil. The last oil I ran was Dexos spec full synthetic and it was NG. (Magnatec Full Syn 5w30) Funny, the Magnatec SS ran well.

Got QSUD non DEXOS 10w30 iN THERE last night AND IT IS ALL GOOD AGAIN.

Id run a decent faux or real synthetic you trust. That 5.3 has pretty high power density. It would have been a z28 enhgine in the earl;y 70s if it appeard back then brought by Aliens (who don't exist around HERE at LEAST)
 
Free would make that decision fairly easy. Tens of thousands of trucks and other vehicles on the road with 300K plus on the odometer running nothing but straight dino and still going strong
 
I kept using Valvoline Max Life blend after my Encore was out of warranty. Like a previous post said. Turbo and GDI, I'd go with gen II. Turbo only (mine), gen I will do. Neither one, they're just calling for the Dexos because they don't want to stock multiple oils at the dealership.
 
Originally Posted By: ARCOgraphite
Dexos spec ain't all that. You just want a good oil. The last oil I ran was Dexos spec full synthetic and it was NG. (Magnatec Full Syn 5w30) Funny, the Magnatec SS ran well.

Got QSUD non DEXOS 10w30 iN THERE last night AND IT IS ALL GOOD AGAIN.

Id run a decent faux or real synthetic you trust. That 5.3 has pretty high power density. It would have been a z28 enhgine in the earl;y 70s if it appeard back then brought by Aliens (who don't exist around HERE at LEAST)




Have you ever found a oil you really liked?
 
Originally Posted By: ARCOgraphite
Dexos spec ain't all that. You just want a good oil. The last oil I ran was Dexos spec full synthetic and it was NG. (Magnatec Full Syn 5w30) Funny, the Magnatec SS ran well.

Got QSUD non DEXOS 10w30 iN THERE last night AND IT IS ALL GOOD AGAIN.

Id run a decent faux or real synthetic you trust. That 5.3 has pretty high power density. It would have been a z28 enhgine in the earl;y 70s if it appeard back then brought by Aliens (who don't exist around HERE at LEAST)


What reason(s) do you give for saying dexos spec 'ain't all that?'

OP,
If your vehicle is out of warranty and isn't DI, i don't think think using the conventional oil would pose a problem.
 
Originally Posted By: Squashtowner
My 2012 Sierra 5.3 is past warranty. I've used DEXOS oil for every oil change. I now have 113000 km on the truck. I changed the oil when the dash reminder told me to on the driver information center. This has tun 14000 km on a couple instances, and that alarms me.

My new job gives me access to free mobil conventional oil. I've been using purolator filters for the past 2 years, wix prior to that.

Can I switch over to non synthetic and make my oil change interval 5000 km? It'd simplify things a lot for me.


Yes you can but as others have stated, the AFM system requires a clean oil.

If switching I would recommend OCI's based on the Severe Service Schedule.
 
another reason is every label aka spec is $$$$ so GM gets $$$ on every dexos spec oil sold!! as noted change more often, even every 3,000 if its free, cant hurt anything!! my aunts 99 jeep gets 6 month changes with Mobil I HM usually about 2,xxx miles, almost all short trips!!!
 
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Originally Posted By: Squashtowner
I changed the oil when the dash reminder told me to on the driver information center. This has run 14000 km on a couple instances, and that alarms me.


That's really not a lot.

It'll go even higher with a lot of highway driving.
 
Originally Posted By: Linctex
Originally Posted By: Squashtowner
I changed the oil when the dash reminder told me to on the driver information center. This has run 14000 km on a couple instances, and that alarms me.


That's really not a lot.

It'll go even higher with a lot of highway driving.
It used to indicate change oil soon around 8000-9000 km. I trusted this measure and wasn't paying attention until I lost oil pressure.

And as I stated before, I'll run our premium dinosaur oil and make my OCI 5000 km. That's still 3-4 months driving for me.

Plus, the 2008-2011 5.3 had AFM, and GM didn't recommend DEXOS in those trucks. My nephew had a 2008 with around 300,000 km on it with no issues other than rust...like my paint-peeling & rusting 2012.
mad.gif
 
An update.

Using Dexos full synthetic oil changes, my truck was burning a qt of oil every 4000 km.
Using Esso/Mobil conventional oil, my truck didn't use a drop of oil in 7500 km when I changed it this weekend.

Sounds like this Dexos certification is a bunch of [censored].
 
Originally Posted By: Squashtowner
An update.

Using Dexos full synthetic oil changes, my truck was burning a qt of oil every 4000 km.
Using Esso/Mobil conventional oil, my truck didn't use a drop of oil in 7500 km when I changed it this weekend.

Sounds like this Dexos certification is a bunch of [censored].


For you, maybe
.

Glad you found something that works for you.
 
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