Oil change intervals

[MarcuM]

2016 5.3 6sp cc 1500 lt 

 

im still driving from wv to Georgia and back for work once a week  and I do a lot of setting parked in my truck just idling 

my engine hrs are 3000hrs@88000 miles 

I’ve been doing the mobile 1 20k filters and oil and changing it at about 50% after resetting my olm

Once during

the oil seems good I just wonder if the excessive idling and long distance highway only (not 85mph) miles is considered extreme use?

no towing just cruis control 70mph max for 550mile trips 

also I have been siphoning out 4-5 quarts of atf through the trans dipstick every other engine oil change since 45k miles I haven’t dropped the pan and was wondering if this was a safe practice to do from now on out or should I stop and let the trans oil get more miles on it ?

 

i just don’t wanna look back a yr from now and wonder if I caused something to wear faster when I could change the way I do things now 

 

thanks 

matt 

[gone_fishing]

I would recommend following the OLM. The algorithm the computer follows takes idling and short trips into account so I wouldn't worry about changing the oil till the OLM says to (usually around 5%). Most of my miles are highway (about 80/20) and OLM warning comes on around 7300 miles.

[Colossus]

Here's the problem with going by the OLM.  it doesn't know what kind of oil filter you are using.  While the oil will most certainly be ok at 8000 miles, if you are using an average filter, it's plugged up and in bypass by 4000 miles.  Make sure you are using a premium filter. 

[Black02Silverado]

I would follow the OLM as well.  What idle time you do isn't as bad as you think since you put some serious miles on the truck every week with the long distance drive. So for the oil and filter you are using I would keep it up and just follow the OLM.

[Black02Silverado]

6 hours ago, Colossus said:

Here's the problem with going by the OLM.  it doesn't know what kind of oil filter you are using.  While the oil will most certainly be ok at 8000 miles, if you are using an average filter, it's plugged up and in bypass by 4000 miles.  Make sure you are using a premium filter. 

If that was  the case then there would be a ton of sludged up engines in this country from those that follow the OLM and use cheap quick oil change places for oil changes that put the cheapest oil filter on the car. 

 

Oil and engine design have come a long way.  At least from my understanding. GM's OLM is set to 7,500 miles.  Our 2016 Suburban is at 7,500 miles when the OLM hits 0% every time.

[Doublebase]

What's 50% for you on the oil life monitor? I'm at 78% right now and I have 2,000 miles on the oil. So I think it depends on how many miles you're at, at that point. Is it 5,000? 4,000? 3,000? More? Less?

 

I personally no longer let direct injection engines go further than 5,000 miles on oil changes. I'm done playing that game. My last direct injection engine was worn out at 160,000 miles, I don't think extended drains didn't it any favors despite using "high quality" oil and filters. 

 

There's a couple things with modern day engines that I believe are "tough" on oil nowadays. Direct injection, low tension piston rings, CAFE regulations, light weight oil and the return of timing chain engines...throw in the addition of turbocharging. Direct injection blasts carbon into the oil. The rings aren't sealing like they used to. Chains are shearing oil, and the carbon is also getting between the pins and rollars, stretching them. I'm just done testing the limits of oil. I'm done with used oil analysis. I'm doing 5,000 mile oil changes and that's it. Call me crazy.

[Black02Silverado]

1 hour ago, Doublebase said:

What's 50% for you on the oil life monitor? I'm at 78% right now and I have 2,000 miles on the oil. So I think it depends on how many miles you're at, at that point. Is it 5,000? 4,000? 3,000? More? Less?

 

I personally no longer let direct injection engines go further than 5,000 miles on oil changes. I'm done playing that game. My last direct injection engine was worn out at 160,000 miles, I don't think extended drains didn't it any favors despite using "high quality" oil and filters. 

 

There's a couple things with modern day engines that I believe are "tough" on oil nowadays. Direct injection, low tension piston rings, CAFE regulations, light weight oil and the return of timing chain engines...throw in the addition of turbocharging. Direct injection blasts carbon into the oil. The rings aren't sealing like they used to. Chains are shearing oil, and the carbon is also getting between the pins and rollars, stretching them. I'm just done testing the limits of oil. I'm done with used oil analysis. I'm doing 5,000 mile oil changes and that's it. Call me crazy.

I'm not bashing or saying anything negative to your post.  I'm just curious as to what you mean your engine was worn out at 160k miles?  Was it drinking oil? What was your oil change intervals with that vehicle?  Again, I'm just curious is all.  

[Doublebase]

2 hours ago, Black02Silverado said:

I'm not bashing or saying anything negative to your post.  I'm just curious as to what you mean your engine was worn out at 160k miles?  Was it drinking oil? What was your oil change intervals with that vehicle?  Again, I'm just curious is all.  

It was using a quart every 700-1000 miles. My oil change intervals were 7,000-10,000 miles. I was using TGMO 0w20 and I also used Mobil 1 full synthetic. I was using the factory filters.

 

Excessive blowby was causing oil to enter the intake manifold (a lot of oil). I'd open up the throttle plate and take a look in there and there'd be a puddle of oil just sitting in there. The electrodes in the plugs were badly oil fouled too. Changed to a heavier weight, it didn't help. Compression test was below specs, tried a wet compression test and it went up. Bad rings. 

 

Were extended oil changes to blame? I don't know. I believe they sure didn't help. 

[Black02Silverado]

3 minutes ago, Doublebase said:

It was using a quart every 700-1000 miles. My oil change intervals were 7,000-10,000 miles. I was using TGMO 0w20 and I also used Mobil 1 full synthetic. I was using the factory filters.

 

Excessive blowby was causing oil to enter the intake manifold (a lot of oil). I'd open up the throttle plate and take a look in there and there'd be a puddle of oil just sitting in there. The electrodes in the plugs were badly oil fouled too. Changed to a heavier weight, it didn't help. Compression test was below specs, tried a wet compression test and it went up. Bad rings. 

 

Were extended oil changes to blame? I don't know. I believe they sure didn't help. 

Yep, you did your homework.  Worn rings.  Interesting that this happened.  Did you do any UOA's as well on the oil?  I wonder if you were high on fuel dilution, which no oil can hold up to and it will wash the cylinder walls and cause increased wear.

[Doublebase]

1 minute ago, Black02Silverado said:

Yep, you did your homework.  Worn rings.  Interesting that this happened.  Did you do any UOA's as well on the oil?  I wonder if you were high on fuel dilution, which no oil can hold up to and it will wash the cylinder walls and cause increased wear.

I did early on, they came back fine...the usual...you have plenty of active additives left, and wear metals are within specifications...try going another 1,000 miles and check back.

 

Fuel dilution was something i considered. I think direct injection plays a big roll with that in today's engines, that and carbon. It's just a lot of fuel pressure spraying directly down on those pistons and walls. And you throw in the low tension (gas mileage approved) rings and I just don't know?? I have been to classes and lately the "buzz" is watch out for those direct injection engines...those timing chains and that oil consumption. The oil is under a lot of demand and it's getting dirty.

 

You're an Amsoil dealer, you must do extended drains, right? No issues on your truck or anything? You've been hearing good things about extended drains with DI engines? Just curious, I figure Amsoil must have addressed it with their dealers.

[Black02Silverado]

I do extended drains when UOA shows that it is safe to do so.  I use Dysonanalysis.  Terry has over 37 years of experience as a Tribologist.  He works with each customer on a one to one basis.  Along with the PDF report he sends a .wav file explaining each line item as you follow along.  If you have any questions you can contact him personally.  

 

Not knocking Blackstone, which I know a lot of people use, their test for fuel dilution is outdated. So it is not very accurate.  Oil testing is very expensive as in the equipment so labs try to do what they can to keep cost down and not updating equipment is one way to do it.  

I tell my customers that if they want to go extended drain then to make sure to get a UOA.  That way I know things are working like they should.  

 

Our 2016 Suburban has had good results with the latest UOA and so I'm extending it out per Terrys advise.  So we will see how far I can extend it.

 

When we had our 2011 Acadia, we couldn't go past 5k on the oil.  That 3.6 DI engine really beat up the  oil. Not to mention the OLM was set to go to 0% at 5k every time.  That is telling me GM kind of knows there is an issue with extended drains on that vehicle.

 

This video is interesting I thought on GM's OLM and now being set to 7,500 miles.

 

GM set OLM to max 7,500 miles.

[MarcuM]

When I say 50% I’m on the 2nd round of the olm

so I guess basically 11,250 miles on a oil change with mobile 1s 20k filter and oil 

 

what about changing trans fluids so often ?

Its only $25 for 5quarts of atf and 5 mind to suck out the pan but am I hurting it more then helping or just stick by the book ?

[Black02Silverado]

13 minutes ago, MarcuM said:

When I say 50% I’m on the 2nd round of the olm

so I guess basically 11,250 miles on a oil change with mobile 1s 20k filter and oil 

 

what about changing trans fluids so often ?

Its only $25 for 5quarts of atf and 5 mind to suck out the pan but am I hurting it more then helping or just stick by the book ?

Transmission fluid change out is always a good thing.  I switch mine over to AMSOIL early, like around 10k miles. Then at 50k miles I pull the pan and change the filter and fluid again.  To me doing this every 50k is well worth it. But I do haul and tow occasionally.  Just make sure you are using the proper ATF DEXRON VI in your transmission. Also there is DEXRON HP out now for the new 8speeds.  AMSOIL's ATL covers both of these specifications.

[MarcuM]

So I’m good on trans fluids but from the way you guys all talk I need to shorting up my engine oil mileage on changes lol

 

[Supreme Pizza]

I check my oil level EVERY time I add fuel, despite the fact that I never have to add any oil. I change my oil every 3,000 miles. I use SuperTech (Walmart brand) full synthetic oil and filter. I also add SuperTech fuel injector cleaner to the fuel tank. The total cost is about $17. That works out to about $500 in oil changes for every 100,000 miles. I think its safe to say that the cost is VERY reasonable, and that changing the synthetic oil every 3k miles will pretty much guarantee that I will not have oil related issues with my engine. 

 

 

 

Edited July 4, 2018 by txab
remove unnecessary pics