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Is Your Gmt-900 Truck Or Suv Using Oil

RyanbabZ71
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Is your GMT-900 using oil  

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Kblaze94 Enthusiast

Kblaze94

Posted
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

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GuyGene
GuyGene

I've been watching this oil usage issue a long time now. Sick of it. My '96 5.7 used NO oil! And I could get 20 mpg highway. Extended cab, loooong bed too. Dagnabbit, GM is running customers away.

Jsdirt
Jsdirt

Yep - they've forced alot of manufacturers to cut corners just to survive.   The EPA has done more harm to this nation the past 20 years than good. Another gigantic, bloated, goverment bureaucracy t

Cowpie
Cowpie

It is a sad testament to GM quality. My factory remanned 12.7L Detroit, 704,000 miles into its second life, only uses about 1 qt per 10,000 miles. Just did oil change on it at 21,580 miles on the oi

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mikemac4498 Enthusiast

mikemac4498

Posted
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.

frankycjr Enthusiast

frankycjr

Posted
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 ?

6Sixathome Enthusiast

6Sixathome

Posted
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.

frankycjr Enthusiast

frankycjr

Posted
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.

Wolfmanjohn Enthusiast

Wolfmanjohn

Posted
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".

frankycjr Enthusiast

frankycjr

Posted
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

Cowpie Senior Enthusiast

Cowpie

Posted
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.

Wolfmanjohn Enthusiast

Wolfmanjohn

Posted
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.

Wolfmanjohn Enthusiast

Wolfmanjohn

Posted
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:

frankycjr Enthusiast

frankycjr

Posted
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.

tyates207 New Member

tyates207

Posted
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.

GuyGene Enthusiast

GuyGene

Posted
Posted

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

Wolfmanjohn Enthusiast

Wolfmanjohn

Posted
Posted

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

 

 

Nay, indeed not!

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