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  1. #1
    SE Level Member Metal Links's Avatar
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    Default Front subframe bushings clunk?

    Lately I have been having a clunking sound when, I brake, give it gas from a stop or especially when driving over uneven pavement. There's no sound when turning or going over speed bumps(just shocks gassing). I replaced my LCAs last year so its not them.

    I've added a strut tower braces recently too, which I believe tighten it up some, putting more stress on the rear bushings. The rubber seems really dry and rust falls out like a pretty red snow when I touch them.

    Should I just order the rears subframe bushings for now, as I'd think they take more abuse than the fronts or is there something else I should look at first? Also, any tips on removing them as they seem to be a pain the ass?

  2. #2
    Killa Bee Scottydoggs's Avatar
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    Default Re: Front subframe bushings clunk?

    lower mounts could be bad if you never changed them.

    98 Buick Regal GS, F body brakes, Caddy STS wheels, tinted tails L36 bottom end, lightly ported heads, 1.95 roller rockers, headers, 2.8, FSIC, 42 lb injectors, a BrandonHall rebuilt trans, DHP tuned and AEM water/Meth injection https://goo.gl/gpV5kW

  3. #3
    SE Level Member Metal Links's Avatar
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    Default Re: Front subframe bushings clunk?

    Lower trans or engine mounts? I've checked the sway bar and it seems fine.

  4. #4
    Killa Bee Scottydoggs's Avatar
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    Default Re: Front subframe bushings clunk?

    Quote Originally Posted by Metal Links View Post
    Lower trans or engine mounts? I've checked the sway bar and it seems fine.
    both of them.

    when bad the engine mount can let the engine twist in the bay, aka the belt side will move 2 or 3 inches when you shift from park to drive, then reverse.

    if you leak oil bad the mount could look like this.


    98 Buick Regal GS, F body brakes, Caddy STS wheels, tinted tails L36 bottom end, lightly ported heads, 1.95 roller rockers, headers, 2.8, FSIC, 42 lb injectors, a BrandonHall rebuilt trans, DHP tuned and AEM water/Meth injection https://goo.gl/gpV5kW

  5. #5
    SE Level Member Metal Links's Avatar
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    Default Re: Front subframe bushings clunk?

    I revved it in drive with the brakes on and friend didn't see any movement of the engine at all and no noise. The mount on the driver side doesn't look to bad...

  6. #6
    SE Level Member Metal Links's Avatar
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    Default Re: Front subframe bushings clunk?

    I replaced the rear subframe bushings and the noise is still there(one bushing was in 1 to many pieces). It happens when hitting the brakes in drive or reverse but only when I'm haven't hit the gas(idling), hitting the gas hard briefly from a stop, or when hitting manholes or potholes. Oddly it doesn't happen when going over speed bumps or rough roads. It sounds lower down.

    I tried moving my tire when off the ground to test the LCAs and didn't get any movement. Also I swear the it's less noisy when its raining.

    I replaced the LCAs with Dorman and Moog problem solvers about 2 years ago. I'm thinking it's struts or front subframe bushings. What else can I test or look at to find this clunking?
    Last edited by Metal Links; 08-24-2017 at 09:56 PM.

  7. #7
    Rarely Here Anymore HighOctaneRacing's Avatar
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    Default Re: Front subframe bushings clunk?

    I'm thinking the trans and/or motor mounts are shot. IK you said you looked but from what you are saying, it sounds like lower mounts. The other things you can check are

    1. Dog Bone bushings
    2. Rack and pinion bushing
    3. Intermediate steering shaft.
    4. re-check tightness of LCA bolts

  8. #8
    SE Level Member Metal Links's Avatar
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    Default Re: Front subframe bushings clunk?

    I tested it more on the drive home just now.

    1) Clunks when hitting gas hard at any speed
    2) Only Clunks when braking at <5 mpg
    3) Sounds more like a Thud(less like metal on metal) when hitting brakes in reverse
    4) Also does it over bumps

    Anyway to check the bushings without replacing them? Assuming your talking about the ones visible from the wheel well. Also I already tighten all the LCAs nuts besides the ball joint with the castle nut.

  9. #9
    Rarely Here Anymore HighOctaneRacing's Avatar
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    Default Re: Front subframe bushings clunk?

    Double check the dog bones. make sure the upper dog bong bracket isn't broken.

  10. #10
    SE Level Member Metal Links's Avatar
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    Default Re: Front subframe bushings clunk?

    The dogbones have about 10 degrees of play when I try rocking the side to side. With the dogbones removed I can move the engine about 2 inches. Should I replace both ends of the dogbones with ZZP poly(cheapest ones I can find)?

    EDIT: It doesn't clunk when I'm turning either when I'm hitting brakes or bumps. Maybe something in the steering then?


    Pictures with Audio, at :15 I shift into Drive out if reverse.
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    Last edited by Metal Links; 08-25-2017 at 03:11 PM.

  11. #11
    SE Level Member Metal Links's Avatar
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    Default Re: Front subframe bushings clunk?

    Believe I have figured it out. There's a gap where the front LCA mounts to the frame so it can slide up and down on the bolt hitting the frame. I ordered new OEM bushings to replace the Moog problem solvers I have right now. I'll update later this week with a answer for anyone who else has this issue.

  12. #12
    GrandPrix Junkie spazzz's Avatar
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    Default Re: Front subframe bushings clunk?

    Tighten the 55 torx more.
    The top and bottom subframe mounts are aluminum, they will bend.
    The sleeve in the bushing should be tight against them with no movement.

  13. #13
    SE Level Member Metal Links's Avatar
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    Default Re: Front subframe bushings clunk?

    There's a good 1/8 inch or so of space. That's seems like alot to tighten. I'll try tightening before I put the new bushings.

  14. #14
    GrandPrix Junkie spazzz's Avatar
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    Default Re: Front subframe bushings clunk?

    Crikey

  15. #15
    I live here. stealthee's Avatar
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    Default Re: Front subframe bushings clunk?

    Check the braces on the core support. I've heard of them making noise that is difficult to track if the bolts are loose.
    2011 Mitsubishi Lancer GTS - Stock DD mode
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  16. #16
    GT Level Member Gregorius's Avatar
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    Default Re: Front subframe bushings clunk?

    Quote Originally Posted by Metal Links View Post
    There's a good 1/8 inch or so of space. That's seems like alot to tighten. I'll try tightening before I put the new bushings.
    Or equal thickness washers/spacers top and bottom. Love the Problem solvers fronts, I would hate to lose them. Shim them bastards!

    Less work, too.
    Magic Link to WarStryker13's Google drive


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  17. #17
    SE Level Member Metal Links's Avatar
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    Default Re: Front subframe bushings clunk?

    Found the issue...The driver side bolt for the front LCA bushing was loose. So the harden steel bolt embiggened the aluminum hole. Driver side is 13mm(side) x 18mm(front), Passenger is 19mm(side) x 18mm(front), measured with ****ty plastic calipers. Also the metal sleeve in the Moog bushing cracked. I tightened them down and the clunk seems to be gone from testing in the driveway, didn't have time to replace the bushings today.

    Any suggestions on what to do? JB well? Metal sleeve?

    https://drive.google.com/file/d/0Byp...w?usp=drivesdk

    https://drive.google.com/file/d/0Byp...w?usp=drivesdk

  18. #18
    GrandPrix Junkie spazzz's Avatar
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    Default Re: Front subframe bushings clunk?

    weld and redrill.
    Those look nasty

  19. #19
    SE Level Member Metal Links's Avatar
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    Default Re: Front subframe bushings clunk?

    That what I was afraid of spazzz, alittle beyond my means right now. The force to keep it mounted seems to be a clamping force on the aluminum so I just need to stop the bolt from pivoting in the mount, would JB weld work to stop the bolt from pivoting? As that should be a compression force which JB should withstand.

    Also how did the metal bushing sleeve crack and why harden steel bolt in aluminum...

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