1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

NV4500 clunk

Discussion in 'Manual Transmission & Clutch' started by Frankenchevy, Jan 7, 2021.

  1. Itali83

    Itali83 Full Access Member

    Posts:
    218
    Likes Received:
    413
    Joined:
    Feb 7, 2015
    Location:
    Maine
    First Name:
    Ben
    Truck Year:
    1982, 1987, 1987
    Truck Model:
    K10, 'burban C10, Jimmy
    Engine Size:
    350, 6.2, 350
    I had an nv4500 in my Cummins dodge. Had the same sound but it was from a worn rear end with too much backlash. I just dealt with it but I’d check the rear end too. Sound travels up a driveline like crazy sometimes.
    Ben.
     
  2. Frankenchevy

    Frankenchevy Lying Dog-Faced Pony Soldier

    Posts:
    4,758
    Likes Received:
    4,969
    Joined:
    Jan 3, 2018
    Location:
    USA
    First Name:
    Jeremy
    Truck Year:
    Square
    Truck Model:
    CUCV
    Engine Size:
    Small
    Both my 14ff and d60 were both rebuilt less than 50 miles ago and my driveshaft is brand new as well. Everything was done at the most reputable axle shop around.

    You’re right though, in person it sounds exactly like automatic transmission driveline clunk. Like when you shift from park on a hill without the parking brake or the clunk you get from R to D.
     
  3. DoubleDingo

    DoubleDingo Drain The Swamp, Completely

    Posts:
    6,181
    Likes Received:
    5,335
    Joined:
    Jul 3, 2012
    Location:
    Right where I am
    First Name:
    Bagoomba
    Truck Year:
    1981, 1965
    Truck Model:
    81-C20 Silverado Camper Special-TH400-4.10s; 65-C20 with 4:57 gears and Borg Warner Overdrive
    Engine Size:
    Carb'ed Vortec 350; 1972 L48 350
    I'm with Andy on this one. Run it like they said. They're sending a new one anyways.
     
  4. Frankenchevy

    Frankenchevy Lying Dog-Faced Pony Soldier

    Posts:
    4,758
    Likes Received:
    4,969
    Joined:
    Jan 3, 2018
    Location:
    USA
    First Name:
    Jeremy
    Truck Year:
    Square
    Truck Model:
    CUCV
    Engine Size:
    Small
    I’m worried that if when clunking it’s ramming into the pilot, it’ll damage the thrust bearings on my crankshaft.
     
  5. bucket

    bucket Super Moderator Staff Member

    Age:
    39
    Posts:
    23,116
    Likes Received:
    9,529
    Joined:
    Aug 3, 2010
    Location:
    Usually not in Ohio
    First Name:
    Andy
    Truck Year:
    '77, '78, '79, '84, '88
    Truck Model:
    K5 thru K30
    Engine Size:
    350-454
    I'm no expert, but I don't think that's at all possible?

    Again, I'd just drive it and use it as much as possible. It will either stay the same, or the real problem will present itself and it will be obvious what needs dealt with.
     
    idahovette and DoubleDingo like this.
  6. Frankenchevy

    Frankenchevy Lying Dog-Faced Pony Soldier

    Posts:
    4,758
    Likes Received:
    4,969
    Joined:
    Jan 3, 2018
    Location:
    USA
    First Name:
    Jeremy
    Truck Year:
    Square
    Truck Model:
    CUCV
    Engine Size:
    Small
    I’ll try driving it again this weekend after I do the lift. I have some u bolts removed right now so I can pick up the right length ones tomorrow. Need shorter ones for the rear and longer ones for the front.
     
  7. DoubleDingo

    DoubleDingo Drain The Swamp, Completely

    Posts:
    6,181
    Likes Received:
    5,335
    Joined:
    Jul 3, 2012
    Location:
    Right where I am
    First Name:
    Bagoomba
    Truck Year:
    1981, 1965
    Truck Model:
    81-C20 Silverado Camper Special-TH400-4.10s; 65-C20 with 4:57 gears and Borg Warner Overdrive
    Engine Size:
    Carb'ed Vortec 350; 1972 L48 350
    I highly doubt a rotational clunk within a closed case will cause any thrust issues on either end of the unit.
     
    idahovette and bucket like this.
  8. Frankenchevy

    Frankenchevy Lying Dog-Faced Pony Soldier

    Posts:
    4,758
    Likes Received:
    4,969
    Joined:
    Jan 3, 2018
    Location:
    USA
    First Name:
    Jeremy
    Truck Year:
    Square
    Truck Model:
    CUCV
    Engine Size:
    Small
    One thing that popped into my head that I’ll look at when I get home...

    In this incredible CAD drawing, the gray bit is my bushing. As you can see in the photo below, the bushing is taller than the gold zinc metal piece. So even if I torque the bolts pretty tight, perhaps those ridges may be responsible for some extra movement.
    80942330-DCD3-47D8-A544-9CFF978BC290.png
    11B9AF50-E728-46F8-9C95-0681953631CC.jpeg

    I might try pulling them out and cutting them off.
     
  9. DoubleDingo

    DoubleDingo Drain The Swamp, Completely

    Posts:
    6,181
    Likes Received:
    5,335
    Joined:
    Jul 3, 2012
    Location:
    Right where I am
    First Name:
    Bagoomba
    Truck Year:
    1981, 1965
    Truck Model:
    81-C20 Silverado Camper Special-TH400-4.10s; 65-C20 with 4:57 gears and Borg Warner Overdrive
    Engine Size:
    Carb'ed Vortec 350; 1972 L48 350
    You may be onto something.
     
    Frankenchevy likes this.
  10. Frankenchevy

    Frankenchevy Lying Dog-Faced Pony Soldier

    Posts:
    4,758
    Likes Received:
    4,969
    Joined:
    Jan 3, 2018
    Location:
    USA
    First Name:
    Jeremy
    Truck Year:
    Square
    Truck Model:
    CUCV
    Engine Size:
    Small
    @SquareRoot , is there any way you can get a straight edge or a 2x4 across the bottom of your frame rails and measure up to the mounting points on your nv4500? I’m wondering if my mounts+my 4x4 steel block is too high...
     
  11. Frankenchevy

    Frankenchevy Lying Dog-Faced Pony Soldier

    Posts:
    4,758
    Likes Received:
    4,969
    Joined:
    Jan 3, 2018
    Location:
    USA
    First Name:
    Jeremy
    Truck Year:
    Square
    Truck Model:
    CUCV
    Engine Size:
    Small
    I’m starting to think it may be the Detroit locker causing the clunking. My driveway has a slight incline so I can point the nose downhill, put the truck in 4wd, pull the rear driveshaft and back up it for a test. If that’s what it is, I may be shopping for an ARB...

    I think the th400 was just better at making the clunk softer...I guess
     
    bucket likes this.
  12. SquareRoot

    SquareRoot Full Access Member

    Posts:
    1,300
    Likes Received:
    1,766
    Joined:
    Mar 18, 2017
    Location:
    Arizona
    First Name:
    Mike
    Truck Year:
    85
    Truck Model:
    K20
    Engine Size:
    350
    I can but I think mine is different from yours. I got a K20 frame with K30 running gear.
     
  13. DoubleDingo

    DoubleDingo Drain The Swamp, Completely

    Posts:
    6,181
    Likes Received:
    5,335
    Joined:
    Jul 3, 2012
    Location:
    Right where I am
    First Name:
    Bagoomba
    Truck Year:
    1981, 1965
    Truck Model:
    81-C20 Silverado Camper Special-TH400-4.10s; 65-C20 with 4:57 gears and Borg Warner Overdrive
    Engine Size:
    Carb'ed Vortec 350; 1972 L48 350

    The slop I mentioned
     
    bucket likes this.
  14. Frankenchevy

    Frankenchevy Lying Dog-Faced Pony Soldier

    Posts:
    4,758
    Likes Received:
    4,969
    Joined:
    Jan 3, 2018
    Location:
    USA
    First Name:
    Jeremy
    Truck Year:
    Square
    Truck Model:
    CUCV
    Engine Size:
    Small
    True. I figured the rise of the crossmember from the bottom flange of the frame wouldn’t change though. I could be wrong, but I thought a W crossmember would be the same on a k20 and k30.
     
  15. SquareRoot

    SquareRoot Full Access Member

    Posts:
    1,300
    Likes Received:
    1,766
    Joined:
    Mar 18, 2017
    Location:
    Arizona
    First Name:
    Mike
    Truck Year:
    85
    Truck Model:
    K20
    Engine Size:
    350
    I'll get the measurement in the morning.
     

Share This Page