I've been a Mobil 1 guy but, may switch after seeing this, plus $18 for 5 qts. at Tractor supply... .
Yeah...I feel the same about the MS6395 certification and Shell has been doing this for awhile so I feel OK with the switch.Bottom line... if you use a Dexos-approved oil (in your GM truck), and keep it changed, you'll be fine, whether you're using a conventional, a blend, or a full-synth. GM doesn't hand out the Dexos certs like candy, so if an oil has it, it's passed some fairly stringent testing.
I heavily debated this switch at my last oil change but chickened out after some research. Went back with valvoline maxlife after using Napa synthetic and had a lifter collapse for a couple miles at the beginning of the oci. Has happened a few times since I've had the truck, but not nearly as frequent lately. I plan to do an oil flush at my next oil change and switch to the t6 5w40 for the broad range. I've had the valley cover and valve covers off and it's relatively clean inside the engine but I figure there's a speck of junk in one of the lifers that causes this random flare up. Oil pressure is a couple pounds lower when hot and ticks a tad so I figure a 40w will help.A lot of guys use the T6 in their gas trucks.
As far as I'm aware (and I'm very aware of today's oil specs) only synthetic meets Dexos requirements. I know maxlife lost it about two years ago. Has really made selling oil changes difficult at work lol. I could be wrong but I know for sure no conventional meets it and pretty sure no blend meets it. However, I mostly deal valvoline so there's that.if you use a Dexos-approved oil (in your GM truck), and keep it changed, you'll be fine, whether you're using a conventional, a blend, or a full-synth.
I've been running 14k oil changes for the better half of 100k now and have no issues to speak of. Comes out about as clean as it goes in too...Is this article true or fake news? dexos came out in 2011, my gmt is a 2007, I don't need dexos. I use it, mobil 1, but that's my business, i change it as close to 3000 as possible, i think that's the key. screw that light on the dash that says your oil is still good, that light/% life is the death of your engine. They didn't give these engines 7 qt pans to let you drive an extra 3000 miles, they did that for the VVT and heat issues. People have trouble with cpas and gunked up screens in the oil pan, that's from not changing oil often enough.
@northcreek thanks for the heads-up, I'll consider shell next time.
General Motors’ dexos brand of engine oil has been out since 2011. The question many have is why GM developed their own oil specification. Understanding how we got to dexos can shed some light on the future of OEM-specific oil specs. Here's what you need to know about GM's motor oil spec.www.noln.net
Interesting to hear this real world feedback from someone who sees a lot of examples (no sarcasm intended).I'm also on the boat of a 3k interval where that I end up around 4k everytime. Have seen some nasty oil after following the olm on my own vehicles and lots of customers vehicles too. Cheap insurance that helps me sleep at night is what I call it, others could say I'm wasting money. It's all personal opinion, biggest thing is changing it regularly.
See it all the time that an afm engine starts tapping when oil gets old and worn out from waiting for the olm to pop up. New oil and it shuts up. Once oil has thousands of miles on it, it'll obviously be deteriorated and begin losing viscosity which they call shearing or something of that nature.Interesting to hear this real world feedback from someone who sees a lot of examples (no sarcasm intended).
Any details worth sharing on the oil / engines (sludge, coking, parts failures, etc.)?
Granted, you don't know everyone's data, but can generally tell if they're at least trying to maintain their vehicles properly, based on observation of other wear items.
Direct injection hammers oil. You can get fuel dilution in the oil close to that of carburetors with DI. That's why OCIs have been rooled back with its usage. GM does 5k on LS engines with DI now and roughly 7.5k on the high feature ones. (DOHC V6, turbo 4 etc.) DI is not easy on oil at all.See it all the time that an afm engine starts tapping when oil gets old and worn out from waiting for the olm to pop up. New oil and it shuts up. Once oil has thousands of miles on it, it'll obviously be deteriorated and begin losing viscosity which they call shearing or something of that nature.
Some cars I see have been 10k+/- on an oil change with conventional oil and its pure black. Then they come back and it's still black. Again and again. They don't change it on time and it stays nasty, all of this carbon stays in the engine to never be cleaned back out to a level that I deem comfortable. Even with a 3k interval it'll still be black and I'd assume would take many 3k intervals to clean out. I see it mostly on Hyundai/Kia with their direct injection engines. Peer down through the oil fill in the valve cover and there's a nice black sludge across all non moving parts.
General varnish /coking / deposits and what have you build up, I'm sure you've had some piece of the crankcase open on some vehicle and seen examples. May or may not cause an issue. But to me, changing the oil frequently is just cheap insurance to prevent such build up and remove the mere possibility that you'll have an oil related failure or sludge issue. And of course not all deposits can be prevented but keeping oil changed before the detergent package wears out definitely keeps them in check.
One thing I can't stress enough is simply keeping the oil topped off. GM is the worst for oil consumption, all other brands also have a few here and there that consume. Run it till the oil is 2-3 quarts low and the oil is wore out. All of the extra heat being dissipated into a smaller volume takes a toll. Have to remember that oil also has a cooling duty inside the engine, thus these newfangled piston squirters to keep the pistons cooler and better lubed, a common upgrade on performance blocks for longevity with high heat in the combustion chamber from pushing the numbers.
One last item that is off the wall, but what's the deal with toyotas keeping their oil so clean? Less blow by and thus less carbon introduction? Why isn't everyone else implementing such a clean running design? You've really gotta push a Toyota to turn the oil black. I mostly see golden brown from them. And ones that change their oil every 3k is still clean when changed again. Toyota is the one brand I could see pushing the envelope on with oil changes.