weird knock/slamming sound

[SubaruNation]

ok so im just driving around normally, not at WOT or anything and i hit a tiny bump and i hear a pretty loud knock.

and the knocks get louder depending on how bug of the item i run over is, or how big the cracks in the train tracks are... etc

this seems to be a regular occurance now and id like to fix it.

wheel bearing maybe?

i dont think it is the struts b/c i replaced them last august w/ brand new OEM ones (bad idea.. i know)

tie rod?

i got under the car and was just pulling on stuff hoping to find something loose and i didn't.

what about a sway bar/endlinks?

could that be it?

thanks for the help,

[ericem]

Maybe the lower ball joints have developed play. You did put the car in the air and try shaking the wheels correct?

[SubaruNation]

Maybe the lower ball joints have developed play. You did put the car in the air and try shaking the wheels correct?

hmmm..

nope
i'll try that though.

all my "testing" was done while the car was sitting on the ground in the driveway.

any other ideas?

[ericem]

lmao!! How in the world would you test for play with weight on the wheel.

[SubaruNation]

lmao!! How in the world would you test for play with weight on the wheel.

this look familiar?

hmmm..

nope
i'll try that though.

all my "testing" was done while the car was sitting on the ground in the driveway.

any other ideas?

[SubaruNation]

i just lifted the car off the ground and there was no play in the wheels.

this does not make sense, anyone have any ideas?

[Legacy777]

Get a pry bar and try moving things. I found my ball joint problem on my impreza that way.

[evolutionmovement]

Bushings as well. Could be front antiroll bar, maybe control arms. Does it seem to have play in it upon turn in or in a turn over a bump? Ball joints aren't as likely to thunk unless they're noticeable when you pull at the top and bottom of the wheel, but that and the tie rods are the main things to eliminate as they're a safety issue, bushings mostly just an annoyance. My front antiroll bar bushings would thunk annoyingly. I could kind of see the bad bushings as they were dry rotted and the rubber surrounding the bar a little wide on the sides, but they didn't necessarily jump out as something obviously bad. Very easy fix.

[SubaruNation]

ok well i will go chimpanzee on my car tomorrow.

i plan on pulling everything that i can reach.

when i wobbled the wheels it was from horizontal, not vertical.

i will try the other way tomorrow.

and the symptoms are:

i am driving and i hit a bump, it really doesn't matter how big it is i feel it and hear a mean thud. the thud is more apparent when driving slow to medium speed.

it also seems to happen when i turn.

WTF.

i have a video that might help out also.. i hope

tomorrow! tomorrow!... ugh

[jamal]

check the top hats, one could be trashed. Or perhaps a spring is unseated from the perch.

[Dynamic Entry]

yeah, check the "Jesus bolt" on the hats

when I installed my newtome suspension one of those guys wasn't quite tight and I had a knock under slight impact




but it could be so many things...... good luck!

[Legacy777]

Actually that would be the "Jesus Nut"

I heard the term "Jesus bolt" used the other day by the local shop owner that will be tuning my car. It was for an ultra-light plane or something. But apparently it's a common term in the aircraft industry.

[SubaruNation]

is this "jesus nut" on the rear struts?
that is where the sound is coming from and i think it's the bushings..
or whatever attached to the rear underside swaybar.. those are easy to move.

i am going out again now 2 double check.

thanks guys

[Aerotech]

All 4 struts have the nut, and if they ARE tight, the top hat (strut mount bearing, inside the black rubber biscuit on top) may have disintegrated. Happened to me long ago, banged like hell over any rough surface.