Rear Knock on Bumps

[ValdesX]

Hey everyone, I know this has been done before but It doesn't seem a conclusive answer has been found.

Every time I go over a medium or large bump I hear a very loud clunk noise on the Rear Driver side, Thought it was the jack, its not.
Could it be the Shocks? I haven't replaced them since I got the car last year and I have put about 60,000km on the car... any advice is helpful, Gracias.

[Zotaga]

I feel ya bro.. I got the same f'ing issue lol.. based off my research.. it could be..

a) Sway Bar Bushings (cheapest fix).. it's like $10-20/bushing and there are 2 of them in the rear holding up the sway bar.. replace them and see if it fixes the clunk..
b) End Links (the nuts could be loose; try and loosen them and then re-torque them to spec.. if there is a lot of play in them after that, you need new End Links)
c) Shocks (push down on the car and let go.. if it goes above where you pushed it down from, your shocks are shot; replace them)

If it happens while you're driving, it could be your brake anti-rattle clips.. if it's just over bumps, then a, b, and c are your best bets.

I have clunks as well but I can't pin point if it's the front or rear.. based off a YouTube video, it sounds like it's my ball joints in the front control arms..

It's gonna suck w/ all the trial and error but I'd start with bushings and work your way up lol..

[aris]

Your car only has 60,000km?

Two years ago I had a knock at rear passenger side ... Went underneath car looked at my shock and it was leaking... Replaced both rear shocks and sound went away.

[ValdesX]

Zotaga - I'll definitely look into those options. Had no idea where to even start haha.
Aris - No haha, It has about 120,000 on it now, just since I bought it last year I have put 60,000 on it. It's a 2009.

[Cab0oze]

Like Zotaga said, except start with the shocks, easiest thing to rule out.
Second up would be replacing the swaybar bushings, can be done in less than 10 minutes if you have your own jacks or ramps.
While you're under there, inspect the end links to see if there are any obvious problems (broken parts, very loose parts, etc)

My bet is on the bushings. Just finished replacing front and rear ones which were ALL causing clunks.

[ValdesX]

Seems from what I have read I should probably replace my shocks anyway. They have 60k+ km on them so ill play it safe with that. Then while I'm down there ill check the bushings. Any recommended sponsors for these parts? Might as well keep it in the family.

[Cab0oze]

Seems from what I have read I should probably replace my shocks anyway. They have 60k+ km on them so ill play it safe with that. Then while I'm down there ill check the bushings. Any recommended sponsors for these parts? Might as well keep it in the family.
whoa don't bother replacing your shocks unless they need to be replaced... You'd just be wasting money. I've got over 100k on both oem sets on my speed and 04 mz3 sedan.

[Zotaga]

I am going to replace my front bushings tomorrow and see if it fixes my clunk.. I can't do the rear because no one sells the Prothane 20mm bushings here :(

I am also going to insulate the rear deck w/ Roxul Safe & Sound to see if I can eliminate the deck rattle. It's a long shot but if it works, :headbang


Like Zotaga said, except start with the shocks, easiest thing to rule out.
Second up would be replacing the swaybar bushings, can be done in less than 10 minutes if you have your own jacks or ramps.
While you're under there, inspect the end links to see if there are any obvious problems (broken parts, very loose parts, etc)

My bet is on the bushings. Just finished replacing front and rear ones which were ALL causing clunks.

[ValdesX]

Well, Part source has a deal on right now, buy one get one for $0.01 so I might as well.
I don't know if they were Brand new or not when I bought the car but I'm guessing like everything else not so much haha.
So none of our sponsors have the rear bushings eh? Guess I'm going to ebay/amazon.

[Zotaga]

I think Garage16 has Energy bushings but from what I read online, they squeek a lot.. it's why I decided to go with Prothane.. the majority of the reviews were positive.


Well, Part source has a deal on right now, buy one get one for $0.01 so I might as well.
I don't know if they were Brand new or not when I bought the car but I'm guessing like everything else not so much haha.
So none of our sponsors have the rear bushings eh? Guess I'm going to ebay/amazon.

[ValdesX]

Gotcha, thanks Zotaga. I'll look around online for those then.

[ValdesX]

http://www.ebay.com/itm/Prothane-Urethane-Bushing-MAZDA-3-RR-Sway-Bar-KIT-19MM-04-05-12-1105-/400525764745#shpCntId

Looks like I can get them for about $22 or so with shipping. That's reasonable.

[Zotaga]

Just watch out for the shipping.. it's absolutely ridiculous..

The shipping costs more than 2x the price of the product.. :\


Gotcha, thanks Zotaga. I'll look around online for those then.

[Cab0oze]

Don't get ripped off paying more than 35 (after shipping etc) for bushings. Just buy OEM for ~22, performance wise they're pretty much identical. Only time when it makes sense to pay more is if you're getting greasable brackets too....

[ValdesX]

Found a TON on Ebay, Prothane Bushings after shipping price is about $24

[Zotaga]

Found a TON on Ebay, Prothane Bushings after shipping price is about $24

The eBay ones that I took the the final order screen all had higher shipping charges than from the main screen. Saw shipping go from $7 to $30 plus brokerage.. Which shouldn't even apply for items <$20.

[MazdaMike02]

Shocks, sway bar links, trailing arm bushings. Check them all in that order, its always one of those 3. Sway bar bushings usually squeak when they're bad.

[kickz]

rear brakes worn ?

[ValdesX]

Nah Breaks all seem fine.

Zotaga, check these.
http://www.ebay.com/itm/Prothane-Urethane-Bushing-MAZDA-3-RR-Sway-Bar-KIT-19MM-04-05-12-1105-/400525764745?pt=Motors_Car_Truck_Parts_Accessories&hash=item5d41322889&vxp=mtr#shpCntId

[Zotaga]

Rear sway bar is 20mm, front is 21mm. That ad says 19mm :/