94 Camry braking problem?

[Toyota343]

Usually when I'm driving my Camry on the highway, sometimes I can feel a slight vibration from the steering wheel. When I'm at 100km/h (60mph) and I release my foot off the gas, the car decelerates at about a rate of 10km/h per every 5 seconds. I'm not sure if it is supposed to decelerate at this rate, but even my old Buick used to coast at 100km/h for a long time with my foot off the gas without any cruise control on. Also, the vibration really kicks in when I start applying the brakes, giving the car a slight wobbly feeling. Even in city driving when I'm smoothly stopping, the car doesn't brake evenly. For example, if I keep my foot in a steady position on the brake pedal, there are certain points where I can feel the brakes quickly slow the car, then softly, then slowly again (quick cycle of sharp, soft, sharp, soft braking + wobbly feeling). I think that the brakes may be causing this vibration especially at higher speeds, but I'm not sure because my mechanic checked them twice and said nothing was wrong with them. The mechanic also aligned the tires, and fixed a power steering leak I had with a specific "stop leak" fluid. Well, the power steering leak started a while ago when the car was on the highway, and the front right corner drove over some big piece of metal that fall out of a truck in front of the car. The mechanic found some sort of crack in the axle or something, but now it's not leaking anymore because of the stop leak fluid. Anyways, I also noticed that after a long drive, sometimes when I touch the outside wheel hub/cover of my right front tire, it is usually hot and sometimes smells too.
Can you guys tell me what's up with my car?

[BMR]

My best guess is wheel bearings. They can cause the brake rotors to warp, which explains the pulsing you're feeling, especially when you feather the brakes. And the hot hub further strengthens that thought.

[BMR]

Originally Posted by Toyota343

I think that the brakes may be causing this vibration especially at higher speeds, but I'm not sure because my mechanic checked them twice and said nothing was wrong with them.

In my first response above, I assumed your mechanic was correct in saying there's nothing wrong with your brakes. That might be a bad assumption. The symptoms you're describing could also be caused by a sticking brake caliper. But if he's a competent mechanic, that shouldn't be difficult to notice.

[ghettosled]

honestly, it sounds like your rotors are warped. it can/will happen over time.

with the slowing down at highway speeds, i would assume you have a 4 cylinder engine. the buick was probably a v6. assuming the buick was also a 3 speed auto (with a 4th as overdrive), the 4 cylinder has to spin faster to maintain 60mph and therefor will slow the car faster when just coasting on a highway.

heat from a wheel is normal after driving. brakes stop the forward motion of the car by applying friction which causes heat, even if not used hard. if the rotors were turning a dull glowing red, then that is excessive and could be a seized caliper.

[Toyota343]

thanks, I'll spray on some brake cleaner to see what happens if they are the brakes. And with the highway coasting issue, I have a V6 engine in my Camry so it should be coasting fine. How would it be easier to tell if it is really a sticking brake issue or a bearing. I also sometimes hear short quick quiet knock from the same wheel (front/right) when I'm driving, and think it's a brake that is sticking and sometimes not releasing. The thing is, is that the mechanic already did notice that this quiet "banging" sound that came from the brake and did some adjustments. But is it still occurring?

[johnjan]

Check your wheel balancing. I had the same issue some years back. One wheel was out of whack and the rim had to be replaced. All the other three were balanced and bingo, the shudders from the brakes were gone.

[BMR]

Ghettosled's right, the pulsing is usually caused by warped rotors. But man, that's Brakes 101. If your mechanic can't diagnose that, they're hopeless.

Anyways, I also noticed that after a long drive, sometimes when I touch the outside wheel hub/cover of my right front tire, it is usually hot and sometimes smells too.

Coupla questions:
1) Do you notice this ONLY on the right front tire?... not the left?
2) How strong is the smell?... do you have to get your nose down in the rim?... or do you smell it just standing there on that side?

[ghettosled]

a quick way to check for seized brake calipers is lift both front tires off the ground. you should be able to spin the wheel by hand (the other side will rotate the opposite way). it wont spin as freely as a rear wheel, but you should be able to turn it pretty easily. if not, the caliper isnt releasing.