GM Truck Club
Founded in 2004 ~ We're the #1 Chevy Truck & SUV Forum.
Silverado & Sierra | Tahoe & Yukon | Suburban & Yukon XL | SUV & CROSSOVER
Results 1 to 4 of 4

Thread: Wiper Motor

  1. #1

    Default Wiper Motor

    On my 1971 GMC 1500, when I run the wiper motor, on every rotation of motor or cycle of the wiper blade it makes a single thump noise. Is that part of the gear that is bad or maybe just hitting something. It sounds like it is coming from under dash, everything under cowl looks good! Do I need to pull the wiper motor out? and is that pretty straight forward?

    Thanks for any help! Gary

  2. #2


    Gary - First off WELCOME!

    Did you take the cowl off? If so, maybe some other trouble shooting...take the arms off and see if it's still making the noise. Also, with the arms off and the cowl off, maybe you can track it down that way without have the blade touching a dry window. Most everything should be under the cowl though.
    TNT - Texas

    First - '68 longbed (lady runs stop sign, insurance gives me a check)
    Then - '81 SWB (stupid stupid stupid...sold it thinking I was going to get something else)
    Now - Finally got my '86 (350, Holley 600, 700r4)

  3. #3
    stephan's Avatar
    Join Date
    Sep 2010
    Far West, Oregon USA,
    Blog Entries


    Welcome to the club Gary. I would do all the checking possible before you pull it out. Run it while you watch the motor & see if you can see it vibrate or jump each time you hear the thumping noise, because you might not be able to see what's wrong with it after it's out. Being a '71 it could just be the motor coming loose or could be the bushing worn on the drive arm.
    1988 Chevy C-3500 2wd (no pic)
    350 c.i. 5.7 L Stock Block, 4 Bolt Mains
    L-31 Vortec Heads, Edelbrock Cam & Intake,
    Holley 650, Flowtech Headers, Magnaflow exh.
    Jet Trans 700R4, B&M Ratchet, 4:10 gears,
    3" susp. lift kit "shadetree"
    No rev limiter, No speed limiter lol

  4. #4


    I like that idea of pulling the arms off first to see if that could be the problem. Thanks!

Similar Threads

  1. wiper motor replace
    By andz74 in forum General Chevy & GM Tech Questions
    Replies: 1
    Last Post: 06-24-2011, 07:15 PM
  2. need new rear wiper motor
    By 99monguse in forum Chevy Suburban Forum (GMC Yukon XL)
    Replies: 2
    Last Post: 12-12-2010, 06:25 PM
  3. wiper motor wiggin out
    By 03 Black Sunshine in forum GM Electrical Tech
    Replies: 2
    Last Post: 05-01-2010, 12:43 PM
  4. Anyone have a rear wiper motor go out?
    By silveradojc in forum Chevy Tahoe Forum (GMC Yukon, Cadillac Escalade)
    Replies: 0
    Last Post: 11-19-2009, 04:53 PM
  5. new wiper motor?
    By 95CTburb19 in forum GM Powertrain
    Replies: 2
    Last Post: 12-16-2007, 03:05 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