'97 Grand Caravan Brake Question

I had my front rotors and pads replaced on my 1996 Caravan about a year and a half ago. I believe that they were warped when I got them. This is how they felt; with light touch they was alot of pulsing which became less as I applied more pressure to the brakes. This pulsing got less and less over the following year or so, as (I'm guessing) the wear caused by the brake pads removed the warp.

Carl

I get the feeling its just something with this van as well. The rotors warp pretty much as soon as you put them on and get progressively worse. Rather than complicate the original post - yes I do have alloys. With the last change, I went as far as using a scotch brite pad on the rim's mating surface. I'm waiting for my magnetic mounting base to arrive so I can do a runout measurement on the front axles & hubs.

If that is the problem, it would have to be solved by replacing whichever of the two front bearing/hub assemblies is bad. If you have access to a dial indicator with a magnetic base, you could take the front wheels off, tighten the lug nuts against the rotors evenly to hold them flat against the hubs, and measure the lateral runout of the rotors. Assuming the rotors themselves are true, any runout would be due to the culprit bearing/hub. Otherwise (if making the measurement is too much trouble), just replace both front hub/bearing assemblies.

I feel your pain - back in 1973, I bought my first brand new car - a Mercury Capri with a hot-running German V-6. From day one, it shook on braking, and not just a little bit, and cupped the tires. The Ford dealers were no help. After a year of replacing this and that on the brakes, I finally figured out by process of elimination that the only thing left was the wheel hub. In those days, they used tapered roller bearings, and apparently one of the pressed-in bearing seats was slightly cocked in the hub, either due to an improrperly machined hub or a piece of dirt behind it, because when I finally replaced the hubs, the problem totally disappeared. A lot of frustration, money, and nasty letters to Ford (you think customer service is bad now - it was way worse back then) before I finally fixed it on my own.

One last thing to rule out before you replace the bearing/hub assys.: Make sure that there's no rust or dirt between hub abd rotor and rotor and wheel causing things to tilt (doesnt' take much). I know you said the problem was there from day one, but you should at least check. However, I suspect new bearings/hubs will fix it.

Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my adddress with the letter 'x')

Good idea - I didn't see this until after making my previous post.

Bill Putney (To reply by e-mail, replace the last letter of the alphabet in my adddress with the letter 'x')

I've not used these type of pads, but does the break-in procedure call for very light braking during break-in? The break-in procedures I've read typically call for moderate to heavy braking during initial break-in to avoid glazing the pads and rotors. Usually, you make a series of reasonably hard stops with adequate cooling time in between to avoid warping the rotors.

It is possible to "warp" the rotors without actually warping them. The theory is that with braking that is too light, you can cause the rotor to have uneven friction around its circumference and this causes pulsing that feels like a warped rotor, when in fact the rotor is just fine dimensionally. I've read that it can sometimes be cured with a series of fairly heavy stops to break the glaze.

If you feel the braking is already so annoying that you are ready to replace the rotors again, then you have nothing to lose by trying a few hard stops to see if it helps.

Matt

We were going through brakes like candy.. Rotors, pads, etc... we moved up to the same rotors and pads that you posted about. What ended up being the problem was the transaxil. Both front end axils went out. The other things, do not by after market axils. We did this, and within 3 months, they went out. Take it to a garage, and have them put them in, so that you have a warranty. Good Luck!!!!

They are new ! This is like the third or fourth set of bendix, raybestos, brembo ....

I just got my magnetic dial indicator base, I'm going to get to the bottom of this today ! ??? Hopefully I'll find a shot hub (s) or axle (s) I wonder if the van fell off of something on the way to the dealer lot. I've owned it since new, this problem has been a royal PITA. Because it's brake related, I've never been able to convince Chrysler that this is anything other than an normal wear item.

Matt,

You may be right. I put the new magnetic dial indicator on the rotors & low and behold one side was out only .003, the other .006" - I measured both sides for runout - the side with the .006 is a thickness problem. Either way - I'm sure that's well within spec. I took my die grinder with a scotch brite roloc to the outside surfaces to rough them up a bit. Made a series of hard stops - under hard braking it is smooth & has powerful braking - easily got the abs working. Its still not quite right on the normal stop. I may take the wheels off and rough up the inside surfaces as well - but I'll first drive around a bit with some heavy braking. ( with my last set of rotors were really warped, a mountain road helped with the warping - the things were toast) I have to say that having a dial indicator is going to be pretty useful for these sort of problems in the future.

Mark

Matt,

You may be right. I put the new magnetic dial indicator on the rotors & low and behold one side was out only .003, the other .006" - I measured both sides for runout - the side with the .006 is a thickness problem. Either way - I'm sure that's well within spec. I took my die grinder with a scotch brite roloc to the outside surfaces to rough them up a bit. Made a series of hard stops - under hard braking it is smooth & has powerful braking - easily got the abs working. Its still not quite right on the normal stop. I may take the wheels off and rough up the inside surfaces as well - but I'll first drive around a bit with some heavy braking. ( with my last set of rotors were really warped, a mountain road helped with the warping - the things were toast) I have to say that having a dial indicator is going to be pretty useful for these sort of problems in the future.

Mark

Hate to say it but perhaps it's your braking technique. I know, I know everyone gets insulted when someone makes a suggestion that they don't know how to drive, everyone figures they should know how to drive straight out of the womb.

But I see this every day coming home on the expressway.

2) Never rest your foot on the brake. The brake petal is not a footrest. Either rest your foot on the accellerator or if using cruise control, on the floor.

4) You should use the brake as little as possible. If you are crusing down the street at 45Mph and 1000 feet in front of you you see a light change to red, you should take your foot off the accellerator and coast to the stop, braking firmly at the last 300 feet. You do not gas it until you get to 200 feet then slam on the brakes. Nor do you apply the brakes lightly at 1000 feet and coast with the brake on all the way to the light.

If you are on the expressway and it's congested, you should pick a crusing speed that allows you to not have to brake. If the average speed of the traffic is

5) Do not use the parking brake if you are one of those people who easily forgets to take it off when you start driving.

If everyone did this driving would be a lot more pleasant for everyone and everyone would also save a lot of gas. Also, there would be far less "caterpillaring" of traffic on a freeway and traffic would actually go faster on the freeway.

Ted