GM Truck Club
THE PREMIER CHEVY TRUCK & SUV FORUM
Founded in 2004 ~ We're the #1 Chevy Truck & SUV Forum.
Silverado & Sierra | Tahoe & Yukon | Suburban & Yukon XL | SUV & CROSSOVER
Results 1 to 8 of 8
  1. #1

    Default Advice? Knocking

    i have a 2000 silverado that i bought about a month now with 102k. i had just changed the oil about a week ago. then about 3 days after that it started knocking, but it started to get cold too, with 10+ inches of snow.
    is this piston slap? if so what can i do to fix it?

    how many of you guys recommend seafoam? is it really safe?

  2. #2

    Default

    no my friend put that in his skylark and it blew up a week later

  3. #3
    Legend

    Join Date
    Feb 2008
    Location
    Red Wing, Minnesota, United States
    Posts
    3,356

    Default

    never had a problem with seafoam, nor have i ever heard of anyone on this sight having a problem with it, just search seafoam, there have been TONS of posts about it
    99 K1500 Suburban LT "THE BEAST"
    Hypertech III, K&N, true dual
    285/75/16
    ___________________________
    Jason

  4. #4

    Default

    used it on my truck. works great!

  5. #5

    Default

    Is this a knock or a rattle when cold? These engines have zero piston skirts and from the first year they came out at 20k plus miles there was a large number of cold engine piston rattles. The condition doesn't seem to effect longevity but it does sound terrible for the first several minutes of operation. It was discovered that removing carbon from the piston did reduce the noise for a short period of time. If you have a knock that is a different issue, a knock will usually get worse as the engine gets warmer while the rattle I refer to will go away as the engine warms up.

  6. #6

    Default

    If it only happens when the eng is cold it is common and doesn't effect the eng. Like the previous post it is a carbon build up issue.

  7. #7

    Default

    also common in the newer gen engines is oil pump drive noise, by your desciption, i would guess put 10w30 in motor instead of 5w30. try to stick to the 5w, as this will help quiet the noise quicker. many of these trucks around here have the common noise, mine included, since 30k. running strong at 165k synthetic always since 30k quieted it down. good luck.

  8. #8

    Default

    thanks alot guys, much appreciated

Similar Threads

  1. knocking?
    By capt sensible in forum Lifted & Offroad Suspension
    Replies: 5
    Last Post: 02-12-2010, 04:06 PM
  2. Knocking noise need help
    By 96BlackSilverado in forum Chevy Silverado Forum (GMC Sierra)
    Replies: 3
    Last Post: 01-12-2010, 03:22 PM
  3. Engine Knocking, don't know what to do
    By silveradokid in forum GM Powertrain
    Replies: 12
    Last Post: 01-06-2010, 08:36 PM
  4. Cold Knocking
    By ippielb in forum GM Powertrain
    Replies: 7
    Last Post: 11-30-2009, 06:32 PM
  5. Knocking in dash
    By jwlurie in forum General Chevy & GM Tech Questions
    Replies: 1
    Last Post: 12-28-2008, 01:56 AM

Tags for this Thread

Posting Permissions

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