Engine occasionally shudders at 45-60 MPH, but only when towing?

Discussion in 'Etrailer.com Trailers and Towing Forum' started by HotelRoyale, Oct 11, 2017.

  1. HotelRoyale

    HotelRoyale Member

    46
    9
    Sep 23, 2016
    I have a problem that occurs only when I'm towing. I have a new-to-me 2001 Coleman/Fleetwood Santa Fe popup, I'm towing with a 2002 GMC Sierra 1500 with the 5.3 V8 and AT. It has the factory tow package. Tires are new and recently balanced.

    Sometimes, but not always, as I'm towing in the 45 - 60 mph range, the engine shudders ... I can feel the vibration through the steering wheel and have a sense of the whole truck briefly vibrating. It only happens when I'm towing my popup, it never happens when I drive the truck without towing. It kind of comes and goes even when it's happening, so it's an intermittent problem, and it doesn't happen every time between 45-60 mph.

    When I towed it last week, it scared the bejeebers out of me because of a previous event. When I bought the pup last Xmas eve, I was towing it home and the engine did a similar "shuddering" ... just before it quit completely. I got the truck and pup towed home; my mechanic said it was the fuel pump and that GM pickups of that vintage are known for fuel pump failures. So when it started shuddering at the start of my recent camping trip, I was paranoid the whole time that it would die and leave me on the side of the road. But it never died and I made it about 1500 miles without the engine dying. It doesn't happen below 45, or above 60 MPH. It almost feels like there is some harmonic imbalance between my truck and my pup at certain speeds ... but that sounds wacky so I'm turning to the wisdom of this forum for any advice you may have. Ever had to deal with something like this?
     
  2. DJS12354

    DJS12354 Member

    66
    13
    Sep 21, 2017
    Northeast PA
    Here's my stupid question: Did the mechanic check the fuel pressure and/or replace the fuel pump? If it was a broader spectrum of occurences, I would suspect a clogged fuel filter. It may be you got a second bad fuel pump.
    Hope you get it figured out and recover your piece of mind!
     
    HotelRoyale likes this.
  3. 1380ken

    1380ken Well-Known Member

    1,356
    113
    Nov 7, 2013
    With out knowing more, I would guess that it is either a coil issue or possibly your locking torque converter. You say the engine quit the last time. Did it start back up?
     
    HotelRoyale likes this.
  4. SteveP

    SteveP Active Member

    632
    47
    May 21, 2015
    My first thought would be rpms too low. Drop it out of overdrive into 3rd or engage tow/haul mode if you have it.

    It could be low fuel pressure, as said before, a bad pump or clogged filter which only shows symptoms under certain load conditions. Had a truck that would do that on uphills at high elevation, felt like it was running out of gas, due to a worn fuel pump.
     
    HotelRoyale likes this.
  5. phoodieman

    phoodieman Member

    667
    12
    May 18, 2009
    Hutto, Texas
    My truck started doing that a few months before my transmission went out. Hope it's not the same for your case.

    Phoodieman
     
    HotelRoyale likes this.
  6. Adam H

    Adam H Active Member

    185
    50
    Aug 22, 2015
    I have found when people swear it's a fuel problem, it's ignition and when people swear it's ignition, it's a fuel problem. If the RPM's were low and the load high, my bet is a coil going out. Any pending codes? If not, I would suggest to go and make it happen for as long as you can to set the code. Therefore you know what cylinder it is.

    Adam
     
    HotelRoyale likes this.
  7. sierrapup

    sierrapup Active Member

    366
    32
    Jun 19, 2016
    my bet is on the tranny, mine did the same thing..[CC]
     
    HotelRoyale likes this.
  8. Halford

    Halford Well-Known Member

    2,470
    108
    Sep 28, 2011
    Santa Clarita, California
    Its Chevy. Buy F-O-R-D. [:D]
     
    Haybale likes this.
  9. Antipodes

    Antipodes Call me Paul

    672
    53
    Jan 28, 2015
    Christchurch, New Zealand
    Agreed, particularly when it only does it towing!
    Torque converter lockup slipping.
     
    HotelRoyale likes this.
  10. Antipodes

    Antipodes Call me Paul

    672
    53
    Jan 28, 2015
    Christchurch, New Zealand
    Fix Or Repair Daily.
    Actually I am a Ford man myself. (Australian Ford)
     
    jmkay1 likes this.
  11. HotelRoyale

    HotelRoyale Member

    46
    9
    Sep 23, 2016
    Wow, thanks for all the helpful tips ... well, except for the "buy a Ford" advice, lol. Geez, I really hope it's not my tranny starting to fail ... I would hope it's not the recently replaced fuel pump and filter, but I know the old mechanic's saying, "Just cuz it's new doesn't mean it's good" ... most expensive damn fuel pump I've ever replaced in my life ($750 w/labor since it's inside the tank]. My mechanic said he used a brand of pump he's had good luck with ... he related the story of one GM pickup owner who cut out an access panel in the tank just so he could replace pumps [plural] easier.

    No codes showing up yet ... as for putting it in tow mode, that function seems to be inoperable as nothing happens when I press the button to activate it?

    Cripes, I may have to think about selling it now ... not sure I can afford a tranny rebuild. Thanks again!
     
  12. Fless

    Fless Active Member

    First On Race Day!
    _
     
  13. Antipodes

    Antipodes Call me Paul

    672
    53
    Jan 28, 2015
    Christchurch, New Zealand
    Hahaha, we started something now.
    GM in Aus & NZ have the Holden. Often mentioned as "Holden together with rust"
     
  14. 1380ken

    1380ken Well-Known Member

    1,356
    113
    Nov 7, 2013
    Try some Lucas transmission additive, that stuff really works. I still think that it may be your coil. What happen the first time before you changed the fuel pump. Did the engine die at highway speed? Did it restart? did it happen more than once?
     
  15. jmkay1

    jmkay1 2004 Fleetwood/Coleman Utah

    2,407
    151
    Oct 10, 2013
    Northern Virginia
    I am not a car person however had it happen to me. Check your transmission fluid. I didn't realize that a rock nicked my transmission line and caused a leak. My car shuttered just like that until it stalled. It always started back up. But something was obviously wrong. The mechanic noticed there was little fluid left in the tank. That's when he discovered the leak. So hopefully it could be something as simple.
     
  16. Halford

    Halford Well-Known Member

    2,470
    108
    Sep 28, 2011
    Santa Clarita, California
    First On Race Day

    C
    an Hear Engine Valves Rap On Long Extended Trips

    General Maintenance Company
     
  17. benandbobbi

    benandbobbi Member

    152
    0
    Dec 18, 2012
    Our 2005 F150 5.4 does same thing. Actually doing it now and getting worse. Last couple times it happened we had the plugs changed and it worked fine for awhile. forgot how long ago recent one was, maybe a year. I am nervous about changing these dang plugs (google ford f150 plug issues!), but i should have the new design in, so i might do it myself this time. I asked the dealer to keep the plugs and mark them. They gave me a box of unmarked plugs - not even sure they were mine.
     
  18. Fless

    Fless Active Member

    Found On Road Dead.
    _
     
  19. Novarich

    Novarich Member

    324
    13
    Dec 8, 2014
    F#$%ed on raw deal. Lol I prefer only a.c. Delco or Delphi replacement pumps. I have had bad new pumps. Changing the fuel filter with a new pump is a must required by the pump manufacturer and will void a warranty. A bad filter will trash a new pump. It could be your lockup converter acting up. As someone mentioned, drop it into drive when it does it and see if it helps. The towing switch changes trans shift points. You won't notice an instant change when you turn it on. Without personally inspecting it, it's hard to tell.
     
  20. xvz12

    xvz12 Active Member

    275
    88
    Apr 6, 2017
    New Plymouth, ID
    Cheap Heap Every Valve Rattles Oil Leaks Every Time...LOL. Actually, my dad was a devout GM man, I learned to drive in a '63 Chevy PU, 3 in the tree, inline 6 cyl....drove that thing like it was stolen...lol
     
    Novarich likes this.

Share This Page