'97 Grand Caravan Brake Question

A while back I posted looking for recommendations for good brake rotors due
to my van's warped rotor syndrome. I wound up getting Raybestos PG + rotors
and the quiet stop plus pads (ceramic) I also replaced the rear shoes and
cylinders, flushed the system & put a combo kit on the rear axles. The van
warped the new rotors while using the lightest braking while breaking in
the rotors and pads. ( and yes, I use a snap on torque wrench religiously )
The steering wheel now literally wags back and forth when stopping for
lights. It just gets worse and worse just like all the other rotors I put
on this thing. I know its the fronts because it stops smooth via parking
brake. I'm thinking now that the hubs must some how be warped, causing
rotors to go all the time. ( I should have resolved the brake issue when it
was new, I already noticed warping on the drive home from the dealer with 24
miles on the odometer. By the time I made my first complaint, I was over
the 12k mark & the dealer said I was SOL, so I've lived with this prob for
87k now.

Any ideas on what to look for ?

 

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

 

Not sure what to tell you. I have never had an issue with any of my vans
I"ve owned at all even with my wife driving them (as she's quite hard on
brakes and driveline) and I've owned 5 of them from an 85 to my current 99
T&C ltd.
Do you have allow wheels? If so there may be some layer of corrosion behind
them and on the hub. But I've had perfect performance from my brakes (even
when I've used the chinese rotors).
Larry

 

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!!!!

 

new rotors

 

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.

1) Never use your left foot to brake. First of all this encourages people
to
rest their left foot on the brake, secondly in a panic stop someone could
stamp down on both the accellerator and the brake at the same time.

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.

3) Harder braking for a short time is much better than light braking for a
long
time. You should feel the weight of your body shift forward during
braking -
if you don't, your not braking hard enough.

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
40Mph, then drive 40Mph. If periodically a gap opens up in front of you
then good, that is what's supposed to happen. Do not drive 55Mph for a
quarter mile on someone's arse then ride the brake for another quarter mile
on someone's arse, then gas it for another quarter mile on someone's arse,
etc. Remember, the only time that
a driver should ever use brakes on a freeway is if there's an accident in
front of him. Brakes should only be used when approaching an intersection
or when you see a cop with a radar gun, and there are no intersections on a
freeway.

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

 

one thing i have noticed with aftermarket brake rotors is they do not fit
around the hub correctly to tight there and when you torq them down they get
warped out of shape and it wopuld be the firsttime a damaged new part made it

 

general min. spec on run out is .002 any more than that and you have a problem