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 5 of 5
  1. #1
    Jr. Mechanic b-radical's Avatar
    Join Date
    Nov 2009
    Location
    San Diego, California, United States
    Posts
    130
    Blog Entries
    1

    Default Noisy engine during idle, e fans, underdrive pullys

    The engine in my silverado is somewhat noisy. It sounds like something loose or rattling during idle. I've had bad experiences trying to fix things that aren't broken, but I'm willing to try to quiet my engine down some if its not too much work. I know th knocking/ pinging is not worth the trouble. I had the ac tensioner replaced about 30k miles ago. I've also had some front end damage so I wouldn't be suprised if something was bent and causing the actensioner to wear out prematurely.

    What can I look for and/or replace to get my engine to run quieter? Are there any parts that are prone to making noise?

    I've seen some trucks wth e fans and underdrive pully's. What are the underdrive pully's for? would e fans help?

    Thanks for all the help


    2000 Silverado, 4.8L, LS
    3" Dynomax cat back exhaust
    Drop-in K&N air filter
    200 amp Nations alternator
    KYB GR2 Shocks
    Bluetooth OBD2 adapter with Torque App on Samsung Note 2
    Custom Stereo System l Pioneer/ Boss door Speakers l 1200 watt Performance Teknique amp l 1 farad capacitor l 2 12" kicker comp subwoofers
    Slider rear window l Locking tailgate, de-baged l 265/75/16 Bridgestone Dueler H/L tires l Fully synthetic oil l Tinted windows
    4l65e upgrades - five pinion planetaries l HD sun shell l high performance band

  2. #2

    Default

    It could be the tensioner for the serpentine belt making noise.

    An Underdrive pulley refers to an aftermarketcrankshaft or accessory pulley (such as an alternator pulley) that is designed to drive a vehicle's accessories at a slower rate than stock. Underdrive in general means the input rate of rotation in a system is greater than the output rate of rotation. However, an underdrive pulley is considered to be an accessory pulley that is larger than the stock pulley, or a crankshaft pulley that is smaller than the stock crankshaft pulley, even though the accessory may not necessarily be underdriven with respect to the crankshaft pulley.

    Underdrive pulleys usually are marketed as a performance enhancing item that increases the torque and horsepower output of an engine by reducing parasitic drag caused by belt-driven accessories, but more importantly by reducing the moment of inertia. Horsepower gains from underdrive pulleys alone are possible. Independent dyno tests have shown up to 15hp increase at the wheels after installing an underdrive pulley.



    If at first you don't succeed, get a bigger cheater bar.

    Current:
    1999 GMC Sierra SLT Z71 | 5.3 "Vortec" | Spectre "Cold Air Intake" | TransDapt TBS | Hypertech 30005 Tune | 2005 Chevy Tail Lights | Denali headlights | Grill Mounted Fog Lights | AWS Bug Shield | 265/70/16 Futura Scramblers | Boss HD Speakers | 2005 Overhead Console | Flowmaster Super 40 mufflers 2N1O | Mostly stock-ish
    Future:
    Bigger Amp Alternator | Electric Fans | Transmission Fluid cooler | Paint (Halfway there)| Interior Restoration/Upgrade with newer model parts | Window Visors (In channel) | Tint | Low-Profile Tool Box | LEDs throughout stock cab locations (68% Done) | And whatever is spurr of the moment
    CVN-69 "IKE-ATRAZ" AIR/V-2 Gear Dawgs

  3. #3
    Jr. Mechanic b-radical's Avatar
    Join Date
    Nov 2009
    Location
    San Diego, California, United States
    Posts
    130
    Blog Entries
    1

    Default

    Very comprehensive answer. Thanks Charles

  4. #4

    Default

    Run some sea-foam thru it and that should stop the pinging/knocking for awhile...your motor will like that

    2009 Chevrolet Silverado 1500 LT Z71 Crew Cab "All-Star Edition"

    Line-X'd Bed
    Line-X'd Custom Brush Guard(Heavy Duty)
    5.3L Flex Fuel
    275/65R18 Toyo Open Country AT2's
    2" Rough Country Leveling Kit(want to get the 2.5 RC kit)
    EGR In-Channel Vent Visors
    Exterior PLUS Package
    Interior PLUS Package
    K&N Drop-In Air Filter
    ProFlaps
    Cat-Back Dual Exhaust
    Black Bowties
    Diablo Sport Predator(AFM Disabled)
    ProFlaps
    Towing Mirrors
    Next Planned Mods
    Blacked out Tail Lights
    Aftermarket Rims

  5. #5
    Jr. Mechanic b-radical's Avatar
    Join Date
    Nov 2009
    Location
    San Diego, California, United States
    Posts
    130
    Blog Entries
    1

    Default

    Turns out it was the idler pully making all the noise. will look in to seafoam, thanks.

Similar Threads

  1. engine near stall at idle
    By wtchevy97 in forum General Chevy & GM Tech Questions
    Replies: 5
    Last: 04-19-2010, 05:41 PM
  2. low engine idle
    By jboyz in forum GM Powertrain
    Replies: 7
    Last: 02-09-2009, 05:55 PM
  3. AC noisy at idle
    By jstein in forum General Chevy & GM Tech Questions
    Replies: 1
    Last: 06-11-2008, 12:35 PM
  4. Engine Idle/recall
    By yack in forum Chevy Colorado Forum (GMC Canyon)
    Replies: 5
    Last: 03-31-2008, 09:36 PM
  5. engine idle erratic
    By new-bis in forum GM Powertrain
    Replies: 1
    Last: 03-02-2008, 08:54 PM

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
  •