Thumps and Thuds

This one;

2- Also a few weeks ago this one showed up. When you are > driving very slow, like turning into a 90degree parking space and you give > the wheel a hard turn to make the turn you can hear a rapid "Thumping" noise > from the steering and feedback into the steering wheel. It's pretty > noticeable, maybe thumping at about 3 or 4 thumps per sec. Happens when > turning either direction and your turning hard (doesn't have to be up > against the limit tho).

may very well be a bad duty solenoid C or viscous coupling. If you have an auto, try putting the FWD fuse in place nad do tight turns in a parking lot. If the problem goes away - possible tranny troubles.

The first may be just rotors, but it may be worth trying rotation the tires to see if it get better - seems that there are a lot of tires nowadays that have 'issues' before the tread wears down. But there are reports of brake pads shifting around and clicking. maybe if a reverse/forward duplicates the problem at least your mech. could hear it.

let us know what you find out OK?

Carl

And I've read that other folks have reported heat shield rattles on Impreza chassis quite a bit. I'd bet that's not unusual.

warped rotor is a definite possibility for the brake shimmy. The mileage is not high, but the thud you describe could come from a worn bushing(s) in the suspension. Either for a strut or a control arm. It could also be a strut. Try the reverse-brake/forward-brake sequence to see if you can reproduce it. Have you ever replaced the half-shafts? The mileage is high enough that this could be an issue, more likely than a worn bushing somewhere.

2 , sometimes 2 to 3 you hear a high frequency rattling noise-intermittently- it's not always rattling. My mech said it was the Cat converter and replaced it. Problem seemed to go away then showed up again a few weeks later. He "tightened" up the heat shields and it went away for a couple of months. One more "tighten" but it ain't gone now. Now I'm Not so sure it was the Cat or the loose shields.

Looking for any suggestions so I don't get burned (like on a Cat Converter). Thanks, Mark

1. I dont know.

1. Check your tire pressure before doing anything. Could just be it needs air. (Get a dial/needle one, not one of those stupid sticks.)

I thought warped rotors were a myth and that modern brakes can potentially leave a deposit on the rotor which causes future braking shudders, if you stop hard and let the pad cool while gripping the rotor?

The theory I heard was a little different. Had to do with stopping hard and leaving the brakes applied, not allowing the rotor to cool evenly and causing warpage. I would think the deposits left on the rotor would easily be scraped off the next time the brakes were applied, but I am certainly no expert.

-Kurt

k. ote wrote:

No, it's pad deposits..."cementite"..and they're harder than the rotor iron, so they don't wear down, while the rest of the rotor does, getting progressively worse.

Interesting... well as interesting as warped rotors can be. :-) Thanks for the info.

-Kurt

CompUser wrote:

I think stoptech (?) has a good essay on this...possibly over on tirerack.com too...