Jump to content

Is your GMT-900 using oil  

1,555 members have voted

You do not have permission to vote in this poll, or see the poll results. Please sign in or register to vote in this poll.

Recommended Posts

Posted

Personally, I would call that claim to be a pile of meadow muffins. That would be 1.5 gallons in 15,000 miles and my 12.7L Detroit Series 60 in my semi doesn't even use more than a quart in that many miles. These GM V-8's should not use more than a quart in 5000 miles..... tops. My '98 454 V-8 would not use a quart between oil changes. So I would politely tell whoever is making that claim that they are breathing too much exhaust.

 

Yea it was the service writer at my dealership who told me this, there's quite a few gmt-900s in my family and they all burn oil though. Things like this will make me jump ship next time and at least give the competition a shot

Posted

I'm on my 2nd go-around with the oil consumption test. In the first 1000 miles I used 3/4 of a quart which dealer claims is within GM specifications but I am going back in another 1000 miles to have it rechecked. In looking at the TSB, it mentions that depending on when your vehicle was manufactured is what fixes will be on it. How can I find what month in 2011 my Silverado was made?

 

On a side note, since I'm not sure if issue is related yet, I noticed that I had a rough idle yesterday then the check engine light came on. I had OnStar check and I have a misfire condition. Not sure if the oil issue is causing an issue with the plugs or something entirely different. While bringing the truck to the dealership this morning I had traction control/stabilitrack errors that kept cycling through the DIC. With only 18k on the truck, I'm wondering what can go wrong next. Beginning to wish I had kept my '06 Sierra that had no issues.

Posted

I have seen this document. In my case GM is replacing the lifters so the engine is being torn down anyways. On top of that, putting a cleaning solution on the top of the pistons is not going to clean the oil control rings. The first 2 rings should keep 90% of the cleaning fluid on top of the piston.

 

I prefer for this to be done right, and the right way is to replace the piston and rings with the other fixes so that the issue is completely resolved. Plus how does the oil being consumed and burned affect the fuel injectors, O2 sensors, spark plugs and catalytic converters ?

Posted

I thought that too about the cleaning solution not getting to the oil rings. Seems like they would fill the block up with a cleaner to get to the oil rings instead of on top of the pistons.

Posted

Just heard back from my Service Manager at the dealership, and GM is going to pay for the replacement of the piston and rings as well. They are ordering the parts and will have me drop the truck off once they all have arrived. It's taken a while, but the dealership did a great job in diagnosing the problem and getting GM's buy in to do things right the first time.

 

Once I get the truck back I'll run it for about 1000 miles and switch it over to Synthetic. I'm hoping my MPG goes up as well.

Posted

Once I get the truck back I'll run it for about 1000 miles and switch it over to Synthetic. I'm hoping my MPG goes up as well.

 

Just my opinion, but I'd leave whatever oil they put in longer than that, with an eye toward monitoring oil consumption and overall competency of the repair. That way, if things go south, they can't blow it back on you for "changing to synthetic too soon after the repair for things to fully seat".

Posted

That's a good point @Wolfmanjohn, so I'll still change the oil after 1000 miles, I'll just use conventional oil and ask the dealership when I can make the switch to Synthetic.

 

What kind of MPG's do you get with your truck, mine is almost exactly the same except that it has the chrome clad 22" rims

Posted

Are you using the oil they put in? I think just about any dexos 1 oil is some level of synthetic blend anymore. i would side with leaving the oil in there for a while just to be sure the problem is solved before moving on to full synthetic.

Posted

What kind of MPG's do you get with your truck, mine is almost exactly the same except that it has the chrome clad 22" rims

 

With the 6.2 motor, I get ~13-14 around town and ~15-17 freeway, with my all-time best being 17.4 mpg. I do the speed limit in town, but run ~75-80 highway. EPA rating is 12/city, 18/highway, 14/ combined. The truck has 10,600 miles on it, and I expect gas mileage will increase slightly as the motor finishes wearing in.

Posted

But Wolf, is ye truck using oil?

 

Nope, methinks a quarter of a quart over the past 10,600 miles (aggregate through all oil/filter changes) doth not qualify me truck as an oil burner. :D:jester:

Posted

I'm getting about the same MPG with my 5.3 right now, I'm really hoping with the fixes for the oil burn problem my MPG goes up. My 1999 Silverado ext cab got 15MPG on average for the 13 years I owned it and that also had the 5.3 engine, but only a 4spd tranny and 3.73 gears in the rear. I may have to bite the bullet and get 17" rims and run a narrower tire to get my MPG back, and get better snow traction as well.

Posted

2010 gmc 5.3l afm aluminum block 19000 miles 1/2 quart every 3000 miles. Noticed at third change.

2009 gmc 4.8l non afm cast iron block 165000 miles barely any loss every 5000 miles.

Posted

Grate, Wolf, we are speaking the same language too. Don't want nary oil using trucks.

Posted

Grate, Wolf, we are speaking the same language too. Don't want nary oil using trucks.

 

 

Nay, indeed not!

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Latest Articles

  • Posts

    • Congratulations Isttype, on your gmc. Really like my 2024 2500hd sle doublecab now with 85,500 miles.  I checked the oil today at 4800 miles since last oil change and barely reading on the stick.  I don't care if GM says it's Acceptable adding a quart every 2000 miles because that is 100% BS, It is not a 1966 Harley Shovelhead! Sounds like it's setting up a future failure like I had with my 1500 6.2l. Other than oil consumption problems, I really like the 6.6l gas and 10 speed is really nice.  Towed a light 4000 pound trailer last week and averaged 14 mpg.  I was pretty impressive that a 7300 pound gas truck did 14mpg towing, Later-
    • Long Term Cold Cycle Limited Testing   Back to the 1990's and XOM's million mile test. Since then there have been others and there will be more. Schaeffer's, AMSOIL to name two. Of these Schaeffer's is the stand alone which I will explain in a bit later.    http://papers.sae.org/600190/:   http://papers.sae.org/850215/:   Up to 75% of  engine wear occurs on cold starts. These two links (above) provide the technical reasons for engine wear. In a nut shell, and by a large margin, cylinder wear is what takes out most motors and even with a pre-oiling system that part of the engine is dry enough on cold starts and cold warm up to pierce Stribeck.   So when you put a motor, or a car, on a dyno for a million miles stopping only for oil changes, (yes fuel is uninterrupted) or break down maintenance, you are depriving the test of the most important part of it's wear cycle. Yes a million is then a pretty easy walk even for a mineral oil under those conditions.    How about cleanliness during the long test cycles? Same thing. Varnishes that stick rings and insulate parts are laid down by repetitive 'heat cycles'. It's the cool down the precipitates the varnishes. These long runs also hinder acidic attack caused by cold start richness and less than optimal cold start ring sealing. They hinder water formation and enhance breathing of the crankcase; the petri dish of acid formation, the first step in sludge formation, amalgamation and precipitation. These motors are also monitored and controlled for water and oil temperatures to within the "normal operating range".      https://www.swri.org/sites/default/files/sequence-iiih-test.pdf Note the test sequence in some boutique oils literature for testing, API IIIH, is not the standard used for the ILSAC G7 testing. Does that mean it is irrelevant? No, not as used. As used as a 'visual guide' it makes it's point. The G7 weighted piston deposit minimum is lower.      Back to Schaeffer's. That was a cyclical test of an engine in fleet service and not a dyno mule and if you saw the video it was not mirror clean but wear was low.    There are oils like BioSyn and other 'Renewable" source oils that taught cleanliness and have proven themselves in fleet testing. Havoline an other example.    The newest ILSAC G-7 test prioritize cleanliness, LSPI mitigation and fuel economy OVER WEAR. In comparison Porsche C30 Specification Verses ILSAC G-7 Specification below:      Some will balk that this graph isn't apples to apples and I will challenge that in that this graph represent the SPECIFICATION and not the any One Oil Performance.   It is absolutely possible to minimize wear, maximize cleanliness and mitigate LSPI etc., It just isn't cheap and currently I see none that are not walking toward profit over performance.     
    • I don't think you will need a split, separate product, etc., the OBD port should be able to deliver everything you need. Since your device would be plugged into it all the time, it wouldn't miss anything.    Hardware in this case will be the easiest part of your project - ELM 327 devices will already deliver all the data you need. Reporting/software is where your advantage/marketability is.
    • I do too. I’ll never be stuck again 😂
    • It has happened to me a few times. I carry a jumpstart-tire inflator with me.
  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...