FSC - Chevy Truck Forum

Thread: 5.7 vortec oil consumption

Results 1 to 7 of 7
  1. #1
    Registered User
    Join Date
    May 2003
    Location
    mn
    Posts
    37
    My Feedback

    (0% Positive Feedback)

    5.7 vortec oil consumption

    I have a 98 GMC Sierra with the 350 vortec in it. It uses roughly 1 quart per 1000 miles or a little less. I bought it with 111,000 on it now it has 118,000.

    It does not leak any externally to speak of, however, the two middle cylinders ( I think #s 4 and 6) on the passenger side seems to be where all the oil is going. There is a lot of buildup on those two spark plugs even after 1000 miles.

    The engine seems to runs good when I put new spark plugs in those two cylinders.

    What could be the likely possble problem? Does this sound like a consistent problem with these engines?

    I am wondering if it could be a fairly easy fix or am I going to need a whole new engine to fix this problem. Hoping maybe its the headgasket or something that is bad in that area.

    Any thoughts, experience, or suggestions would appreciated. I am going to bring the truck into a mechanic to get the transmission replaced (details on another post) and I am thinkg of having them dig into the engine a little to see if the can find the problem.

  2. #2
    The Pair
    Join Date
    Aug 2002
    Location
    Texan stuck on Oak Harbor, WA
    Age
    37
    Posts
    297
    My Feedback

    (0% Positive Feedback)
    have compression checks done on the cylinders. do you have any smoke out the tailpipe? you might have problems with the rings in those cylinders with a ootta oil.

  3. #3
    Registered User
    Join Date
    May 2003
    Location
    mn
    Posts
    37
    My Feedback

    (0% Positive Feedback)
    Thanks for the reply Shorts.

    Yeah, I should have mentioned that I really don't notice smoke coming out of exhaust, *possibly a very little at start up, but the exhuast looks normal when its running.

    If it is the rings I would suspect that a rebuild is in store for the near future and a compression check will quickly tell me if thats the problem or not. Is there any possible problem it could be and not require a rebuild? What what could be some possible causes for bad rings in these two cylinders?

    I am hoping for the best.

    Kyle

  4. #4
    Registered User
    Join Date
    May 2003
    Location
    mn
    Posts
    37
    My Feedback

    (0% Positive Feedback)
    Okay, had a compressoin check done on it, all cylinders are +/- 2psi so the rings are not bad.

    The only thing the the mechanic could come up with was leaky valve guides becuase you would not notice it in a compression check becuase the valvles would be closed.

    Does this sound like a very probable answer? Could it possibly be something else?

    I want to get the valve guides redone on the passenger side head and it will run about 800$. Quite a bit cheaper than putting in a new engine. But I want to be as certain as possible that it is nothing else when they start on it.

  5. #5
    Registered User 021500HD's Avatar
    Join Date
    Jan 2003
    Location
    Waldorf, Md
    Posts
    860
    My Feedback

    (0% Positive Feedback)
    It could be something as simple as a leaking intake at those two intake ports and a gasket replacement might fix it. Too hard to diagnose over the internet, check the intake gasket thread in the General Discussion forum.

  6. #6
    Registered User
    Join Date
    May 2003
    Location
    mn
    Posts
    37
    My Feedback

    (0% Positive Feedback)
    Well, I had the dealership dig into it and it turned out it was the intake gasket. It was actaully pulled into the lifter valley on the 4 and 6 cylinders. Runs great now.

    Thanks for your replies.

    Kyle

  7. #7
    Proud Parent of a 5.7L V8 Z71Silverado98's Avatar
    Join Date
    Oct 2002
    Location
    C.C. TX
    Age
    33
    Posts
    478
    My Feedback

    (0% Positive Feedback)
    i was having a prob. w/ oil consumption. i was low 1 1/2 quarts about 1,500mi after an oil change. go down to O'reilys or local auto parts and get a can of Restore. this stuffs been around since my grandfathers time, restores seals, helps restore compression, blah blah blah. $5 can, try it before you go into costly repairs, it worked for me.
    98 Chevy Z71, PowerAid TBS, K&N FIPK, 2.25" Dual 50 series Flowmaster, SSBC Big Brake Kit, 305/70 ProComp Xterrains on 16x8 Am. racing Terons, 2" lift, CFM Tech Throttle Blade,B&M Elec. Shift Kit, Vette Servo, Trans-Go Shift Kit, Hooker Super Comp Headers, Descreened MAF.

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •