ProtoFly

Hi All,

Just purchased a used (not certified) 2007 Suburban, with 101k miles, from a Chevrolet dealer. Hoping that by purchasing at a dealer where there is some reputation involved, they don't have 'lemons' on their lot.

Anyway..Had a chance to start it cold before purchase, no noises, no smoke. Drives wonderfully, no clunks or creaks.

Before I signed on the line, I browsed through as much information on here as possible, and it -seems- like the biggest potential issue is the oil burning. I can only get limited service records, but it doesn't appear that it was a problem at any point with this truck, which was serviced by same dealer. Carfax does show a couple of repairs, but nothing of major concern.

Dealer fixed power folding mirror and rear door power window switches, which were inoperable, but beyond that, everything functioned as designed.

So, what to look out for? I already ordered the Range V8 AFM eliminator, hoping to head off any nastiness of the AFM and oil burning, although I'm not necessarily thrilled with having to worry about battery drain, so might just go for a tune later, as it is already past any warrantee.

Anything else major that I should be looking for?

Thanks,

Darryl

ProtoFly

OK, no replies yet, so I suppose I'll post:

First thing I did was add the Range Technology 'V8', to disable AFM, maybe head off the oil burning issue - which I don't know yet if it is a problem on this particular vehicle. In any case, no more annoying V4 mode - all V8 all the time.

Next, I posted a question in General Tech, regarding what diagnostic software is good.

After spending the weekend driving around, putting some miles on (few hundred), no noticeable drop in oil level (too soon to tell), but really loving the truck.

Whoever the previous owner was, they took good care of it. Interior (including dash) is nearly perfect, although I do have a couple of the interior door handles with the peeling chrome. No rattles, which is a nice departure from my last GM. Has nearly new Michelins all around. Some curb rash on the wheels, but that's OK.

in2pro

Lets see some pictures

joeincharlotte

Range AFM Disable huh? I searched around on this site and don't see much information. Do you, or does anyone have any feedback on this? Will this fix the AFM woes?

LTL4life

"Oil Burning issue"? wondering what engine you have. I have an 07 2500 with the 6.0
Getting close to 98,000 miles on it and mine doesnt burn/ leak a drop. I change the oil twice a year, Before winter and after the spring and never had an oil issue.

joeincharlotte

I've got the 5.3 and went to check the oil, not even registering on the dipstick. No drips on the driveway, only thing I can attribute it to is burning due to the AFM.

ProtoFly

I have the 5.3 'flex fuel', with AFM. I'm almost 100% positive that the 6.0 doesn't have AFM in 2007 (I -think- that's standard now though), so you wouldn't have the issue.

AFM disables 4 cylinders for 'economy', think 'displacement on demand' in the old Cadillacs.

In any event, the AFM system has been rumored to cause carbon buildup on the piston rings of deactivated cylinders, eventually leading to burning oil (which you may or may not notice in the exhaust).

I've only had the truck for less than a week, so I have no idea if it has the problem (yet) or not.

ProtoFly

So far, the only feedback I can say is that it definitely disables AFM, keeping the engine in V8 mode full time. The only thing I don't like about it is that it draws a small amount of power even when the vehicle is off. I may purchase an OBDII extension, and wire the (+) to a keyed fuse, as others have done.

v8 – Range Technology | AFM Solutions for GM Cars, Trucks & SUVs

It's too early for me to know if my 5.3 has developed the problem. I simply don't have enough miles on it.

Although I did purchase an 'extended warrantee', I have a feeling that piston rings gunked up aren't covered, short of a catastrophic failure, which I doubt it will have.

ProtoFly

Given that you have less than 100k miles, you may have good results taking it to a dealer, and having them do the 'oil consumption test'. You might have to jump up and down a bit, though, as it seems to depend on the dealer as to whether they will give much assistance.

I believe that ultimately, GM replaces the pistons and rings, after trying everything else. Best to get them to start the process of 'everything else'...

My premise in using the AFM disable is that if I -don't- have the problem, I hopefully will avoid it. If I do have the problem, I'm hoping that running in full V8 mode all the time will help 'de-gunk' the rings. I'm prepared for the eventuality that I may have to replace the pistons and rings myself at some point, though. REALLY hoping NOT. ;-)

ProtoFly

More soon, but here's one.