its been 2,000 miles since my first oil change and today my oil level lightcame on, it was about 2Q short, anyone got any idea why my engine is useing oil like this and would synthetic make a difference cause thats whats in there now. any help pease

 

Who changed it last ? The Vortec motor has a TSB for oil consumption. I beleive it states that is is acceptable for the 4.8, 5.3 and 6.0 to use up to a quart every 2000 miles. I think that is b.s. that they can do that. If someone can post a link to the TSB page you can read it yourself. The one I know of is no longer there. I think 2 quarts is waayyyy to much if after only 2000 miles. IMO it won't make a diff weather or no it's synthetic. I do use Mobil 1 10w30 though and have not lost more than 1/4 quart between changes(every 3000 miles). If you did it yourself or trust who did, let your dealer know and keep a close eye on it. If it does it again, start raising hell.

 

dump quetion what dose TSB stand for? <img src="images/icons/confused.gif" border="0">

 

Technical Service Bulletin

 

I run Quacker State Full Synthetic in my 5.3 and haven't lost more then a 1/4 quart between oil changes either. One thing to think about is Who changed you oil? They take almost 7 Quarts of oil and it someone put in the normal 5 quarts like the old 5.0's and 5.7's That could be your problem.

 

[quote]Originally posted by Low99ado:
<strong>One thing to think about is Who changed you oil? They take almost 7 Quarts of oil and it someone put in the normal 5 quarts like the old 5.0's and 5.7's That could be your problem.</strong><hr></blockquote>
Your 5.3L takes close to 7 qts.? <img src="images/icons/confused.gif" border="0"> I dump in 6 qts., and it's perfect.
FWIW, mine has used oil since I bought it, but it's gotten less and less with each oil change. It used ~7/8 qt. in 2,700 miles on the last oil change. It went through 1.5 qts. the first time around. We'll see what it does on this change. I'm running dino oil and will continue to do so. I personally wouldn't run synthetic with less than 5,000 miles. I ran dino oil in my SS until a little over 5,000 then switched to Royal Purple. I couldn't get that car to use oil if I tried!

 

i think im lucky, i can keep my oil for a while and it drains out an entire bucket everytime, i guess it doesnt like the taste of oil <img src="gr_grin.gif" border="0">

 

At first I thought you had an 8100. I think they technically take 6.5 quarts with a filter change.

It's not uncommon for big blocks to swill oil. Hell mine only has 3,200 miles on it and has used nearly 2 quarts. If after 6-10k miles it's still swilling 2 quarts I'll take it in, otherwise, I hate to give you the GM excuse, these new engines CAN use around a quart of oil, especially during break in. Just be thankful you don't own a ford or dodge big block motor, they're standards are even worse.

 

No oil loss when not towing. 1000 miles of hard towing will use 1 to 2 quarts.
Too many down shifts to second gear @ 70 + M/H, too much WOT in second & third. Automatic & cruise control may downshift 3 to 5 times on each hill. Below 65 M/H much less shifting, much less oil gone.

 

Mine had the same exact problem, took it in and they changed the PCV valve. NO OIL LOSS SINCE!!! even towing a trailer 90 mph for 300 miles in 3rd gear.