Contour Enthusiasts Group Archives Forums General Troubleshooting Shaking while braking

i replaced the brakes a year or so ago, now while braking it get a feeling in the foot that its shaking, but nothing in the wheel? when i turn sharply at low speeds i go hear i thump of some type in the front end... brakes or suspension?

the tump from the front end could possibly be a brake related issue but sounds more like a problem with one of you constant velocity (CV) axles, not a cheap fix but as far as problems go one of the cheaper ones.

CV HALFSHAFT (REMANUFACTURED) for a
1999 FORD CONTOUR
LEFT HAND SIDE (SITTING INSIDE VEHICLE) (Change)
WITH AUTOMATIC TRANSMISSION (Change)
ANTI-LOCK BRAKE SYSTEM (Change)
Core:$60.00 Price:$69.99

CV HALFSHAFT (REMANUFACTURED) for a
1999 FORD CONTOUR
RIGHT HAND SIDE (SITTING INSIDE VEHICLE) (Change)
ANTI-LOCK BRAKE SYSTEM (Change)
Core:$60.00 Price:$99.99

Hey, I was just getting ready to make a post similar to yours. I have a 98 SVT that has the same problem. However, you really only notice it when coming to a stop from higher speeds (at least it is more noticable then). It definitely is coming from the front end. So you are saying it is most likely warped rotors? Let me give you a short background of my car prior to this problem.

Back in October I lost control of my car going around a corner pretty fast and ended up going over a pretty high curb (front end first). None the less, the accident could have been much worse, but it messed up the bottom of the bumper, the two front rims where dented (since it hit pretty hard), messed up a control arm, and one of the struts. None the less, it was all fixed/replaced. Ever since then I have noticed this shaking problem (as described above) when braking. What do you think.....

It could be warped rotors but I would look elsewhere first. Wapring rotors happen gradually overtime, I dont see how and accident could cause them to warp. Usually it starts out as light viberation, then as they become more warped it gets worse.

Where else should I look?

I suggest not to spend a dollar untill you check for the lower contlol arm's bushings. Specially the rear ones. When they start to go, you start to sense funny things on the front end. Just take a look. Probably you have two problems, the thump and the shake.
Best lucks...

What are the physical signs of bad bushings (what do I look for)?

Maybe I have my information wrong but I'm pretty sure that you can't make your rotors "warp". They're cast iron and braking doesn't generally produce enough heat and sufficient cooling to "warp" a rotor. What you do probably have are brake pad depostits left on the rotor from braking from high speeds. I don't remember exactly what this process is called but I know it exists. I have had it happen to my brakes and Baer told me to do the "break-in / seating" process to it. Make 5 consecutive stops from 80mph. This should burn off excess deposits.

Jack

Ah yes you've have heard correct, "adherent" braking vs "abrasive" braking. I can't find that neat article on here, PM me, I believe it's on my PC somewhere if your interested?
We all gotten so use to saying warped, it's easier to say and the adherent so much harder to understand.
The article was written by a former brake/chassis engineer (I think) back in the LEmans GT-40 days.
I know I've upset many mechanic friends by saying this but then offer to print out the article and then they still????
Old habits are hard to break?

Paul
I'd say after hit the curb like that, check all the suspension related parts first. Never forget in 1970 my German landlord spun his VW square and the rear wheel slapped the curb flat and snapped the axle inside the transaxle. Sometimse it does take much to break the bank!
Paul