I have a 2019 GMC sierra with a 6.2L which I bought new. It just turned 100k. I really like the truck and it has been very dependable. I change the oil every 5k up until now. Ive been reading or watching videos on running or not running higher viscosity oil in the crank case. A lot of differing opinions on this and would like to hear what you guys think? The owners manual calls for 0-W20 which is the lightest Ive used but thats what's called for so Ive used it since the beginning. Some people say that GM has fuel economy standards they have to meet or get fined and one way to do this is to decrease oil viscosity which improves gas mileage. Some people say this is at a cost of engine protection and you could run a 5-W30 for better protection. Some people also say if you bought the same vehicle in Europe or CAN they recommend 5-W30 because they are not held to same fuel economy standards? I dont know if this is true or not? The heavier weight offers better protection and Im wondering if I should switch. 0-W20 seems thin but it's worked so far but would like the engine to last as long as possible so Im contemplating this change? Perhaps I should just stay with 0-W20 and change every 3k, or switch to 5-W30 and change every 5k or just do nothing? Factory doesn't recommend additives either but they recommend a heavier viscosity for the 4/6 cylinder engines. Any thoughts on this?

 

Stay with the 0W20. Modern engines have VVT. If you went to 5W20 because it gives better protection, then why not go to 20W50?

 

As Jessie sz the newer engines have Variable valve timing which uses the engine oil like a hydraulic fluid to change camshaft timing. Not like older engines that just use oil for lubrication alone.

 

0-W20 in summer time in hot climates and pulling heavy loads. From all I read and videos are killing crank bearings. It's the manufacturer getting every bit of gas mileage they can. To save $50 a year in gas. You are right, same vehicle in Europe or CAN 5-W30. Massachusetts is not Texas. 5-W30 going into my new car here.

 

GM recommended going to thicker 0W40 when the bearing problems started showing up. A friend of mine who has a 6.2 has been using 5W30 year round without any problems.. his is way out of warranty so it doesn’t affect that. but his engine has always been a noisy clicky clangy thing

my non GM 2019 Truck has over 400,000 kilometres on it ..still going strong. 4 cyl which has used 5W30 regularly from the beginning.

 

GM has recalled nearly a million 6.2L V8's and one of the fixes is switching from 0W-20 to 0W-40 (assuming the engine hasn't already toasted the bearings). Other 6.2's in GM's fleet require 0W-40 (like the LT1/LT4 in the Camaro/Corvette).

That said, your engine isn't included in that recall, and you're already at 100k. Any damage done from too light of an oil would have already been done. If its been working that long, why change?

 

I will ad my 2 cents. Winter time 0-20 is good, summer time 5-20 in real warm weather 80 plus suggest 5-30. Yes new engines do have vvt solenoids but the weight does not come into play. What comes into play with the vvt solenoids is the oil needs to be kept up to the proper level & clean oil is very very important. I am glad to see you change your oil every 5,000 miles and not paying attention to what the factory suggest....You will find everyone on this topic has a different opinion

 

The newer 6.2Ls can and do run on 5W-30 oil. There's several guys I know that do and have driven them for years. It won't hurt. Might hurt gas mileage a smidgen, and will kill a warranty if you're still under the factory warranty and get caught using something different (if you have an aftermarket warranty- read your coverage rules about that, if anything).

Look at other 6.2L engines in use and you'll see different weights recommended as well, like European 6.2s. Strange. The 0W-20 is for EPA considerations. So if I had 5W-30 and no warranty, I wouldn't hesitate to use it. Just make sure it's quality oil.

The 0W-40 thing is for the band-aid thing that GM will bless only after the engine is 1) within the danger-zone of VIN's affected by the 6.2L crankshaft clearance fiasco, and 2) the dealership checks the engine and deems it not to be an immediate issue. So it's not a great idea just to automatically do the 0W-40 on your own. Unless you're out of warranty and don't care.

If you think that's bad looking for an extra 0.0005 mpg, the alternator circuitry is ultra-silly. It basically kicks up amp load on deceleration to help with engine braking. No sheet. I kid you not.

 

Thanks for you guy's input on this. All valued opinions. FYI my truck is out of warranty and Im just trying to make it last as long as possible. I spoke to the the local Chevy dealer today and asked about it. He looked up my VIN to see if there was a recall or service bulletin and said there was nothing.
The mileage is not important to me as much as the friction protection.

 

Last summer I helped a good friend repair his 2017 6.2 that started knocking and locked up solid in a matter of 30 seconds. Right at 100K miles. He is **** about maintenance and was using the 0W20 oil. His spun 2 rod bearings and ruined the crankshaft. Had to replace the crankshaft and two rods.

More disturbing was that 4 of the pistons had broken ring lands that had to be from detonation. He is a car guy and swears he never heard it pinging or any other indications of detonation. One thing I found while researching it is that the 6.2 GDI actually requires 93 Octane fuel and I dont think he had been using it. He is now for sure and he went with the 0W30 instead of the 20. He also replaced all of the injectors in case that had anything to do with the broken pistons.

Just as important as the "weight" of the oil is that it meets whatever Dexos specs that GM specifies for that engine. If it does not have the Dexos seal on the bottle I would not use it.

 

I go between 87 & 89 and rarely a bit of 93 octane. I just assumed 87 would be good and never looked in owners manual for recommended fuel. I do a lot of highway driving too if that matters? I just changed oil yesterday with royal purple and added a little friction protection in there. 2017 may have slightly different issues than 2019 but I haven't any solid info.
Were you able to replace crankshaft with factory pc along with rods and bearings and just replace broken rings? Any machining required?

 

The actual ring lands on the pistons were broken between the first and second ring. No machining other than a light hone and I checked the balance on the new crankshaft.

We replaced the crankshaft, 2 connecting rods and all of the pistons. Crank and rods were GM. Pistons were Silvolite who makes an updated coated piston for the 6.2 GDI New rings and bearings. New oil pump just because.


He thought the same thing. And his made it to 100K before giving up too. Look at page 271-272 https://cdn.dealereprocess.org/cdn/s...sierra1500.pdf

I don't think the fuel had anything to do with the bearing failure but the piston damage was classic detonation.

The 5.3 can use 87.

 

Where are you at in Eastern Mass ?

 

If you're not certain about the best oil, you could use a 50/50 mix of 0W20 and 5W30, or something like that - just a thought.

 

Obviously not just an oiling issue on that 6.2 with ring lands beaten out. I run 0W20 in Winter and 5W20 in the Pentastar V6. Some of the earlier ones recommend 5W30. I know some Jeep guys run 5W30 or 10W30. No oil burning or cam follower failures at 165,000 km, 10,000 km max oil change intervals with premium synthetic. I just switched to Restore and Protect for everything. I switched my Daughter's Elantra to 5W30 synthetic. It says 5W20 on the cap but in the manual, 5W30 and 10W30 can be used. I only switched to help oil burning. I think GM is trying to limp their shitty 6.2 through warranty with 0W40. It might do absolutely nothing to save these poorly machined motors. There is now 0W15 and 0W8 oil. Interesting to see how those motors are holding up. Pretty sure Canadian vehicles use the same light oils. I know even the new Duramax 3L uses a 5W30 Dexos D spec oil. Not cheap oil and they burn it too. Way too many new engine failures from multiple manufacturers. Lake Speed Jr figured poor machine work and metallurgy was more to blame for failures.

 

Very true at least in the case I worked on. What is interesting is that we could not find a single "smoking gun" cause for the bearing failure. The front two rod bearings were killed but the rest of them really looked fine. I tend to believe it was leftover manufacturing debris that finally came loose and got in an oil passage. I regret not looking at that closer at the time. Hyundai/Kia had a big problem with that a few years ago and I think Toyota is fighting it right now.

I am certain the piston issue was from detonation but what caused it ? I do know he was just using 87 octane fuel but you would think all of the knock sensors etc would have sensed any detonation. And there were absolutely no codes in the ECM. The only other possibility is GDI LSPI Do a search on GDI Low Speed Pre Ignition. Very interesting subject.

 

Fascinating: https://nasaspeed.news/tech/engine/p...ction-engines/

Thanks for that! Seems mostly focused on turbocharged direct injected engines, but given they still don't exactly know what causes it, you can't fully rule it out.

 

Not sure how long the 6.2 has been in production, but here's this: go back as many model years as you can and see what weight of oil the factory recommended then.

All things being equal (VVT, etc) I bet it was heavier than 0W-20.

 

Mendon MA

 

Good read. You definitely want SN+, SP and Dexos 1 Gen certified oil. This is another reason why I don't like direct injection oil engines. Ideally, everything should be port and direct injection, this is another reason. Of course Toyota has both on their TT V6, just shows everything needs proper execution during manufacturing or disaster strikes. Sucks that a truck engine basically needs expensive Premium gas for a long life.

 

The reason you need premium fuel is the 6.2 has about 10:1 to 11.5:1 compression ratios, depending on year/application. It CAN run on non-premium, but it's not recommended and the ECM will adjust like a **** so you basically turn it into a 5.0L doing it. Adding regular, IMO, is like when you're 200 miles from home, running on empty, and premium can't be found. You don't want to make it a habit. Mid-grade is better than regular. So with a 6.2L, buy the highest octane they got available. If you still want to do regular, you should've just bought a 5.3L.

It simply amazes me when people buy high compression engines and then feed them regular fuel when it states right in the owner's manual to run premium for best performance. You may think you're saving money buying cheaper gas, but in the long run, you'll be paying later. The knock sensor has to sense a knock before it adjusts anything, and by then you're already starting to do damage.

 

True, many modern direct injection NA V8's are 11.5 and 12 to 1 compression. I found almost no difference in mileage or power on the Pentastar, despite the Premium being non ethanol. But all the cars were non PUG and only 10.2 to 1, only port injection too. Another place the Premium gas may help, is a superior additive package over regular gas. That also would help less carbon build up.

 

 

Well I guess that says a lot about today's engines.

 

0 weight oil makes....well, 0 sense.
Think about 0 weight oil. Rub some between your fingers just once you will feel the lack of lubricity. Its just not there. How can one expect the hammering action transferred to the rod bearings on the power stroke to cushion the bearing surfaces...it cant and wont for long.

The proof is in all the chiseled apart low mile warrantied engines with blued rods & main caps.

The only reason the DA's came up with it cuz it saves 0.00001mpg... period.
That's cuz the auto manufactures get a kick back from big brother. $$$$$ = stupidity = $$$$$...its cyclical.
Want to find the problem...FOLLOW THE MONEY!

Run 5W20 or 5W30 in your modern junk with prolong and everything WILL BE FINE....
99% of all knuckle draggers over think oil.

0 weight oil makes the same sense as a fur lined sink or a gasoline powered turtle neck sweater.

 

The 0W part is not being selected for fuel economy. It doesn't impact fuel economy. Its the cold temperature viscosity and as such, only really impacts startup. Fuel economy tests are done at operating temp, not cold.

The 20 part? THAT is being selected for fuel economy over a 30 or 40 weight oil.

 

Excellent summation. If you live in an igloo, you'll be glad you had 0W-? oil in your crankcase and not straight 40w. As it gets warmer, those specialized molecules swell to make the oil thicker, thus should be up to 20/30/40 weight, whatever that 2nd number is. If you live in the south, you're likely not going to need a 0W-? oil. There's even a 0W-8 oil call out for some engines. For real.

0W-20 is likely the MINIMUM the engineers decided they could get away with on the 6.2L. We know the engine can take higher viscosity. In some of the owner's manuals like the Corvette, they specify to run heavier weight oils on their performance cars on track days, and then change oil back to normal after the racing.

2018 Corvette owner's manual page mentions 15W-50 for racing, then go back to 5W-30 afterwards for some of the higher performance models. Also add additional oil. Maintenance scheules move up to 15 hours of racing changes for the transmission fluids and 24 hours for the rear gear fluid.

 

Interesting GM says 15W50 for racing. I know GM and Dodge use 0W40 in certain performance models as well. I am just wondering if 0W40 will save a single engine. Way too many low mile engine failures from all manufacturers. If Toyota is haven't engine failures with 0W8, it kind of throws that out. Just like all the cam failures, even with high ZDDP oil. None of it makes sense that it is just thin oil. DOD may play a part on the massive amount of roller failures. Remember when you could use factory roller lifters even with aggressive cam swap. Arguments, who knows if an actual solution will come up.

 

son in law inherited a 22 gmc denali pickup.he got the recall notice from gm so took it in.they dropped the oil and took a sample.replaced filer,filled with 5w30 and replaced the oil fill cap with one that said 5w30.week or so later they called and told him the oil analysis came back fine.i told him next oil change bring it by and i will change it and take a sample so he can send it to an independent lab,i just am not very trusting of these manufacturers anymore.
the earliest 6.2 engines i have seen were in 07 in the denali and escalades.and they take 5w30

 

Did you remove the VVT when you had it apart or is that not an option with the newer 6.2? I have a Pontiac G8 with the 6.0 and the DOD on those cars is a known weak point and a lot of guys remove it as a preventive measure. Mine only has 55,000 miles on it, but it's always in the back of my mind.

 

My conclusion: 5 W30 changed every 3-5k along with 93 octane and avoid cold starts when able and hope for the best.

 

Before I retired I bought a 6.2 VVT / Direct Injection Chevrolet Silverado LTZ and the required oil was 0-20 oil and Premium gas only. These engines were the 1st ones with lifter failures which still not sure GM got around doing a recall on. Anyway from the time that I took ownership I changed over to Mobil 1 0-20 and change oil every 3000 miles. So what have I gotten from the same routine as I follow with all of my vehicles? The truck now has 199,000+ miles on it with the only problem of a single broken valve spring at 145,000 miles. When the valve spring was replaced I also had the cylinder deactivation turned off. Just this year when we made a trip to Commiefornia did I change only for the trip to 5w-30 mainly because of the temperature of 117* that we were driving in. Turning off the cylinder deactivation cause a loss of 1mpg with the truck only and 1.5 mpg if towing a 8.5' x 24' enclosed trailer. Still average 22 city and now 25 hwy, down from 22.5 city and 27.4 hwy which I account to the mileage on the truck. No other issues with the truck to this date.

 

I can't see any issues with that, 5W30 should be fine all year. If outside, a block heater helps a lot on particularly cold days. Use Top Tier gas and Premium Synthetic with the Dexos 1 Gen2 and you should have no issues with those drain intervals. I mentioned using 0W20 Restore and Protect, meets the Chrysler spec. Someone from Florida mentioned 5W20 or 5W30 ,weather dependent. I said weather says 0W20. Definitely needed, months well below freezing to come in Saskatchewan. My Wife parks for 8 hours with no plug in, most days.

 

And the debate goes on.......

 

And on...

 

Now we're really going down the rabbit hole. What do you engine guys think:

 

I vote for the 5/20 oil, and deactivate the AFM...... very bad for the engine and you might lose 1 mile per gallon. Let it breath on 8 cylinders full time!

 

Yes, one of the reasons for oil consumption and lifter failures in modern motors, probably more than thinner viscosity. As far as a 0 Winter weight, some of us experience -40 weather and thick oil on startup isn't good. I do run 5W20 in the Summer in my Challenger. I did put 0W30 in the 5.9 Magnum in my 2000 Dakota and run 10W30 or 10W40 conventional in the Summer. I may just run Restore and Protect 5W30 all year round. But the 0W30 and going from probably 8 gauge to 1 gauge battery cables made a huge difference in cold starts. I also run 750 to 850 CCA batteries for the same reason.

 

https://cartipsdaily.com/6-2-afm-years-to-avoid

 

I just changed the oil in my 25 Kia Sorento today. I used the OE 0W20. If the viscosity is incorrect then I suppose the engine already has damage since it's already at 20k miles.

The oil fill cap says 0W20, so...