Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

Exhaust drone

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by kustom71, Dec 22, 2003.

  1. kustom71

    kustom71 1/2 ton status

    Joined:
    Mar 14, 2003
    Posts:
    117
    Likes Received:
    0
    Location:
    NJ
    Anyone else hate the exhaust drone that seems to fill the cab.The constant humming is driving me crazy i almost hate to drive the truck.Anyone have any suggestions for different mufflers that are a little quieter in the cab,these summit turbos are killing me!!!
     
  2. Muddytazz

    Muddytazz 1 ton status

    Joined:
    Jun 30, 2002
    Posts:
    20,073
    Likes Received:
    0
    Location:
    Salem, Or.
    Stock replacement mufflers are really quiet.
     
  3. Confedneck

    Confedneck 3/4 ton status

    Joined:
    Nov 1, 2002
    Posts:
    5,236
    Likes Received:
    0
    Location:
    Lehigh Acres, Florida
    any fully welded baffled muffler will have less drone than one filled with glass packing.. flowmasters perhaps or some other brand of welded mufflers..
     
  4. Leadfoot

    Leadfoot 1/2 ton status Premium Member

    Joined:
    Nov 28, 2000
    Posts:
    3,112
    Likes Received:
    1
    Location:
    Western Massachusetts
    Is this in the K10 or the K5 (looked at your profile)?
    K5's are a big resonator due to fact that the "bed" portion and cab are one unit and made of sheet metal. I have noticed people that have removed carpet and sound deadener have more drone (as makes sense). Do you still have all carpet and such in place (if not, that is helping to contribute to the drone). Also, where are your mufflers located under the rig and where are the tailpipes exiting, as both of those can contribute to drone. Certain mufflers (mostly louder/deeper tone ones) tend to drone more, whereas a stocker or quieter muffler helps keep droning to a minimum. Also what tires do you run? I have seen people have a fairly aggressive tire that will hum and transmit to the body and have people blame that on the exhaust (until they swap to a lesser agressive tread and it goes away). Just some things to consider.
     
  5. kustom71

    kustom71 1/2 ton status

    Joined:
    Mar 14, 2003
    Posts:
    117
    Likes Received:
    0
    Location:
    NJ
    77 k10 long bed mufflers under bed tailpipes straight out back.I have to try something,thanx for the responses! /forums/images/graemlins/thumb.gif
     
  6. Leadfoot

    Leadfoot 1/2 ton status Premium Member

    Joined:
    Nov 28, 2000
    Posts:
    3,112
    Likes Received:
    1
    Location:
    Western Massachusetts
    Things to try:

    Quieter mufflers (most likely to help)
    Moving mufflers furthur back from cab (probably not likely due to $$$)
    Sound deadening (what do you currently have on your cab floor....carpet or rubber mat, also is there front to back sound deadener?)

    I had a similar problem to you with my 80. Many times I liked having the loud (somewhat obnoxious) exhaust for screwing around and for doing truck pulls, but when I was driving it back and forth to work, it got annoying real quick. I lucked out in that my exhaust system (at least the mufflers) were clamped on, and I was able to find quiet mufflers that fit right in place. I would change them out when the exhaust system was cold/cool and it would only take about 10 minutes start to finish. I had the best of both worlds and it help getting a sticker (with being able to use the "quiet" mufflers).
     
  7. Grim-Reaper

    Grim-Reaper 3/4 ton status Author

    Joined:
    Feb 17, 2000
    Posts:
    7,385
    Likes Received:
    0
    Location:
    Atlanta
    [ QUOTE ]
    any fully welded baffled muffler will have less drone than one filled with glass packing.. flowmasters perhaps or some other brand of welded mufflers..

    [/ QUOTE ]

    I had 40 series flows and at hwy speeds you couldn't hold a converstaion with the passenger. Now the 3 inch pipe on my 88 burb has just enough of the muffler rotting inside to have a nice little rumble without being iritating inside.
     
  8. mofugly13

    mofugly13 1 ton bucket of rust Premium Member

    Joined:
    Oct 6, 2002
    Posts:
    2,813
    Likes Received:
    2
    Location:
    San Francisco
    I have a single 50 Series Flowmaster and the drone is downright annoyng. The muff is tucked up tight to the body and the tailpipe exits down right behind the rear axle. I think these factors may have something to do with it. I am going to try a 70 series Flo when funds allow.
     
  9. slimlynn1

    slimlynn1 1/2 ton status

    Joined:
    Apr 9, 2003
    Posts:
    336
    Likes Received:
    0
    Location:
    Hamden, CT
    I just put dual 3" Dynomax Bullet race mufflers on mine. I dumped them down right before the rear axle. Much quieter than the open headers.
     
  10. Confedneck

    Confedneck 3/4 ton status

    Joined:
    Nov 1, 2002
    Posts:
    5,236
    Likes Received:
    0
    Location:
    Lehigh Acres, Florida
    i have cherry bomb turbo 2 mufflers and they drone pretty bad.. i will eventually be going to long tubes and 2.5" with 12" long 2.5" dynomax bullets.. i agree with moving the mufflers back and that may help..
     
  11. rjfguitar

    rjfguitar 3/4 ton status GMOTM Winner

    Joined:
    Aug 28, 2002
    Posts:
    9,097
    Likes Received:
    144
    Location:
    california
    I have 2 40 series flowmaster with no cats and 5" tips dumping on both sides on the back of the axle. I get no droning except for just a little at about 1,000rpm but it vibrates everything including the pictures on my wall in the house when it's running. /forums/images/graemlins/thumb.gif
     
  12. kustom71

    kustom71 1/2 ton status

    Joined:
    Mar 14, 2003
    Posts:
    117
    Likes Received:
    0
    Location:
    NJ
    i had american thunders from my chevelle on it and people heard me from a couple blocks away and at 5am thats not really what i wanted to hear along with my neighbors(not that i care what they say)and now with the summit turbos i cant hear anything from the time i give it gas to the time i let off.I need to find something that flows but is not annoying inside.Mufflers are as far back as i can get them and pipes are out the back.Pipes are 2.25 all the way and i dont even have headers on it yet! /forums/images/graemlins/truck.gif
     
  13. 84_Chevy_K10

    84_Chevy_K10 Banned

    Joined:
    May 30, 2001
    Posts:
    17,669
    Likes Received:
    0
    Location:
    IL, USA
    I don't know how you can hear it that loud in a pickup. I had 12" glasspacks, straight pipes, and now 40 series flowmasters on my shortbed, and I can hardly hear them, even with the windows open.
     
  14. K5Jimmy

    K5Jimmy 1/2 ton status

    Joined:
    Sep 21, 2000
    Posts:
    1,141
    Likes Received:
    0
    Location:
    Lake Dardanelle/Logan Co, Ark
    I run Headers, 2 1/2 pipe to HiFlo cats to Magnaflows, 2 1/2 pipe to 3" Bologna tips 45* at the rear corners, no crossover because I like the way duals sound....plenty of attitude for the stop light Grand Prix, not enough to annoy the cops...very comfortable exhaust note while cruisin'....Dynomat deadener inside doors, tailgate, headliner, rear panels, and front carpet...I get more wind noise from the wing windows than anywhere else...I'm told my truck sounds good...I can hear the stereo just fine....it's what works for me /forums/images/graemlins/thumb.gif
     
  15. JIM88K5

    JIM88K5 1/2 ton status

    Joined:
    Apr 27, 2001
    Posts:
    1,384
    Likes Received:
    0
    Location:
    Vancouver, Wa
    Have a cross over pipe installed. It will sound better inside and out.
     
  16. kustom71

    kustom71 1/2 ton status

    Joined:
    Mar 14, 2003
    Posts:
    117
    Likes Received:
    0
    Location:
    NJ
    im gonna redo the carpet and and add sound deadener to the back wall and floor.the crossover is an idea i didnt think about but ill try it thanx /forums/images/graemlins/thumb.gif /forums/images/graemlins/truck.gif
     
  17. Mastiff

    Mastiff 1/2 ton status Premium Member

    Joined:
    Jul 21, 2002
    Posts:
    2,755
    Likes Received:
    48
    Location:
    Tucson, AZ
    My K5 gives a pulsing sort of vibration at highway speeds, especially under load (like going uphill). I'm 90% sure it's because I have very poor isolation of the pipes from the body. The shop that installed the pipes totally clamped the mounting rod around the attachment points and it was really bad. I went in there and cut some off so there is some rubber isolating it, but not much. One of these days I'm going to have a shop set it up right so the pipes are hanging from rubber like most normal vehicles. I'm hoping this will cure the problem.

    Bottom line: check out the isolation from the pipes, especially on a K5 where the entire bed area will resonate like a drum.
     
  18. slider

    slider 1/2 ton status

    Joined:
    May 7, 2001
    Posts:
    547
    Likes Received:
    0
    Location:
    Whidbey Is. Washington
    A cross over pipe will get rid of the exhaust drone booom whatever you want to call it. It equals out the exhaust pulses from the two cylinder banks. I had the same problem but the cross over got rid of it.
     

Share This Page