HELP: 93 Toyota Corolla vibration problem!

The brake hose was an excellent idea as both calipers had already been replaced.

No that's not excaltly whay he said. I can understand how you could read it that way. Hut it isn't exactly what he said. It MAY well be the caliper, but it can be either one of them or both. There are several other options as well.

The word "draggin" doesn't mean it WAS the brakes being on. It CAN but it can also be something else.

Try to re-read that without being so dogmatic. Don't get too invested in a single solution.

Does that mean the brakes were dragging? It MAY. But not necessarily.

How does he know that? Hear it?

No fault here. I just prefer to eliminate all the easy stuff first, the stuff that's easy to check for free before tearing a car apart. It MIGHT be a bad caliper. Like I said from my time in the parts business, rebuilt parts are problem children. I am assumiong that he did NOT go out and buy NEW parts from the Toyota Dealer at 10X the price of a rebuilt on a 15 year old car with almost 300,000 miles on it. I don't know WHY .. Silly me. Most people willing to shell out $300 per for NEW calipers most likely would be driving a newer car. JUST A SUSPICION.

Maybe you MISS that he HAS taken it to a mechanic SEVERAL TIMES.................................................

Funny? Want to watch some video from NASCAR and Indycar racing? How much heat sort of depends on SPEED doesn't it? a Corolla is HIGHLY unlikely to hit a speed to break into flames EVEN with a NITROUS BOOSTER - however - heat does build up from wobbling wheels. Maybe as your DRIVE smartass you might want to look out your window and see those pieces of rubber from Truck tires. Do you EVER wonder just a LITTLE why those big chunks of rubber are there? Think HEAT has a LITTLE to do with it Mister KNOW IT ALL?

But Jim don't you think when the hoses HAVE been replaced a couple times that we can RULE THEM OUT and move on to something else? Let me ask you,. just HOW MANY SETS of brake hoses should he replace, in YOUR "expert opinion" before he starts looking at something else? 10? 20? 50? a THOUSAND? Should he change brake hosts 10 times a day EVERY day for the next hundred years? In your mind there is only ONE possibility. BRAKE HOSES. You MISS that he has replaced them! LET IT GO!

HEY GUY he REPLACED the hoses. WHAT part of that do you NOT understand? HE DID THAT - TWICE! Now let it go.

Yeah I believe in the obvious and EASY first. The things you can eyeball and shadetree.

I also said that even though he has NEW calipers that rebuilt calipers have an EXTREMELY high rate of being BAD. He needs to yank them and look. OR replace them under warranty.

SO HAVE THE HOSES SMARTASS!

No actually it can't be anything else. That is what you clearly do not understand. There is nothing else on the car (excluding the engine cooling system) that can absorb that much energy and not fail catastrophically. A bearing can certainly get hot. But if a bearing is generating enough friction to slow the car down that much is not going to last more than a few miles or less. The brake rotor is the only thing down there that can absorb that much energy and survive for anything more than a short period of time. There are only 2 possibilities - either the caliper is sticking or something in the brake fluid circuit is preventing the fluid from flowing back to the master cylinder. If whatever is getting the wheel hot were anything but brakes it would have been over a long time ago.

Maybe you missed that he said the problem started right after he took it to the mechanic the first time.

-jim

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That's EXACTLY what he said, it's a cut and paste from HIS post. I see reading comprehension isn't your strong point!!!!!!!!!!!

But it does point to the brakes as being the problem, no ????

Ther's that reading comprehension problem again !! Do you think a bent wheel is making the rotor turn blue ?????

You're right. He states the brakes are dragging causing the car rotor to turn blue and the car to slow down, maybe he should do a tune-up.

Keep reading, he explains it pretty clearly.

That's the way to do it, diagnosis is the first part of any repair. But he should be checking the BRAKE SYSTEM for a BRAKE PRBLEM. It will do absloutely nothing to check tires, wheels, balance, alignment and all the crap that WIL NOT CAUSE a brake problem.

It MIGHT be

If you buy from a reputable rebuilder you have less chance of getting a defective part. If you buy cheap chinese crap you end up with cheap chinese crap. But I have even found BRAND NEW parts that were bad out of the box.

Wrong !!! He has taken the car to someone who calls themself a mechanic, but is not capable of finding the problem OR fixing the vehicle. He needs to take the car to a REAL mechanic who is capable of DIAGNOSING the problem and FIXING the car. He has checked everything on the car EXCEPT the brakes and even had him replace what was probably a perfectly good set of tires claiming they were "defective". Sound like he is taking it to a tire store flunky instead of to a real shop.

Show me ONE instance of a tire that starts burning from driving too fast, just one !!!

- however -

And they burst into flames ????? LMFAO

I don't need to wonder, I know what causes it. I can tell you that they don't get hot from friction with the air flowing over them.

yup... definitely brakes. Dark horse would be a wheel bearing that's not getting hot but is loose enough to cause brake drag, but quite likely it is a straight up pure brake issue. Either a bad caliper or a return port blocked in the master cylinder. might be pushrod length too short but that wouldn't explain why the issue only started after the calipers were worked on. gunk in the MC is likely though if for whatever reason the mechanic pushed back the pistons of the old calipers without opening the bleeder screws first. Or it could be something truly weird like a busted spring inside the MC allowing the piston to block the return port or something like that.

If I were the OP I would take a jack and a wheel chock along with me for a ride, and go somewhere where there are wide, flat shoulders to pull off. Then once the issue starts, jack up the suspect corner. Try to spin the wheel with the car in neutral. If it spins hard, crack open the bleeder screw on the caliper, let out a little fluid, tighten, and try again. If it spins easy now then you know it's a hydraulic brake issue, either in the caliper or the master cylinder. If it still spins hard look for a mechanical issue like stuck sliders or a loose wheel bearing.

If it turns out to be a hydraulic issue I would then check the opposite rear wheel and see if that spins any harder than the rear wheel on the same side (assuming a diagonal split system.) If it does, the problem is likely related to the master cylinder. If it does *not,* the problem is likely the new caliper. (although it

*might* not be, as someone correctly pointed out, if the rear brakes are drums and not adjusted tightly.)

nate

Okay YOU KNOW - he needs to keep replacing those brake hoses. AGAIN AND AGAIN AND AGAIN AND AGAIN AND AGAIN AND AGAIN. Don't worry that they don't fix the problem. YOU ARE RIGHT and I am 100% WRONG. The ONLY thing it can be is the BRAKE HOSES.

REPLACE THEM AGAIN.

Okay you two WIN. He NEEDS to replace the brake hoses AGAIN! Keep changing them until it is fixed. Get 2,000 pairs and keep replacing the hoses again and again. I was wrong and YOU two are right. It can ONLY be the brake hoses!

Speed doesn't cause it just makes the heat higher. Do you EVER watch Indycar racing? EVER? Maybe you missed the race last year when Danica Patrick's car wrecked because her left front tire burned up from getting bent? NEVER SEEN EVEN ONE? I guess to never paid much attention to any NASCAR races. Doesn't happen EVERY race, but it happens frequently enough. WATCH.

There's that reading comprehenxion problem again, huh ? Were do you see brake hoses metioned above ?

If you bothered to read the entire post you would have seen what I recomended, here's the part you snipped:

He has taken the car to someone who calls themself a mechanic, but is not capable of finding the problem OR fixing the vehicle. He needs to take the car to a REAL mechanic who is capable of DIAGNOSING the problem and FIXING the car. He has checked everything on the car EXCEPT the brakes and even had him replace what was probably a perfectly good set of tires claiming they were "defective". Sound like he is taking it to a tire store flunky instead of to a real shop.

You would think the inreased airflow would help cool it, no ?? Especially on an open wheel car!

Once in a while, yes.

How does a tire get "bent" ????

Nope, I've never seen a bent tire before.

I watch NASCAR racing all the time and I've never seen a bent tire there either.

As painful as it is to read your many horseshit posts, I can only imagine how unpleasant it would be to hear you talk, since it seems that your thoughts are filtered by your ass before they come out.

Toyota MDT in MO (a "resident" expert that makes it by here about once a month on average -- nice one, krap!)

Hi Group,

Here is an update just to keep you all interested. I replaced the caliper and rotor on the problematic side under warranty. I figured that the rebuilt caliper that was installed 3k miles ago was crap (they often are). This did NOT fix the problem. So, I called another mechanic that suggested that the atmospheric valve in the brake booster may be going bad. I disconnected the booster from vacuum and taped off the lines so that engine performance would not be hindered. This did not fix the problem either. Even without power brakes, that wheel still heated up. Therefore, we are down to the following... please comment:

1. the slides the caliper rides on may need lubricating.
2. the master cylinder is bad.
3. there is some obstruction in the hardlines

I'll keep you posted. thanks again.

If the problem is easily repeatable then it should be easy to determine:

A) Which brakes are dragging (is it just one?). B) Does the hydraulic cylinder at the wheel have hydraulic pressure.

At this point your conclusion that it is affecting only the one wheel seems likely to be wrong. Have you noticed any pull to one side when braking or when the problem occurs?

-jim

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I would also check the freeplay in the pedal, make sure you have enough. Also make absolutely sure that you do not have a wheel bearing issue. check your list as well though those are all possibilities.

good luck

nate