pulsing brakes

[Oppie]

I had Saturn do a front brake job on my '01 lw300 about a month ago.
They were supposed to change the pads and turn the front rotors.

Was all good when I picked it up and stopped nicely. But over the last few
weeks there has been an increasing pulsation on stopping. Tried pulling the
E-brake lightly while moving and there was no pulsation so I assume that the
issue is in the front still. If it is not a suspension problem, it may be
that the rotors have warped somewhat. The pulsation seems to be minimal at
first and gets more pronounced with successive stops. Seems to bear out
warpage. Anybody encounter this before? Afik, these are factory stock
rotors.
Oppie

 

[tom]

I had Saturn do a front brake job on my '01 lw300 about a month ago.
They were supposed to change the pads and turn the front rotors.

Was all good when I picked it up and stopped nicely. But over the last few
weeks there has been an increasing pulsation on stopping. Tried pulling the
E-brake lightly while moving and there was no pulsation so I assume that the
issue is in the front still. If it is not a suspension problem, it may be
that the rotors have warped somewhat. The pulsation seems to be minimal at
first and gets more pronounced with successive stops. Seems to bear out
warpage. Anybody encounter this before? Afik, these are factory stock
rotors.
Oppie

I'm sure the work is warrentied if you went to a good service shop.
Immediately return, since these problems might effect the car's
braking ablities.

imho,


tom @ www.CarFleaMarket.com

 

[blah blah]

It can also be a hot spot, look for blue'ish areas. If you have a
micrometer you should check the thickness of each rotor in at least 5
spots. I never turn rotors on cars anymore. Its generally cheaper,
faster, and easier to just buy new aftermarket rotors. I think
incorrectly torquing the wheel might also contribute to warping.

(For roughly 20 bucks you get a wore rotor turned and what do you get? A
thinner rotor. Or for 20 bucks you can buy a new rotor. At least for my
car you can.)

 

[Jonnie Santos]

I had Saturn do a front brake job on my '01 lw300 about a month ago.
They were supposed to change the pads and turn the front rotors.

Was all good when I picked it up and stopped nicely. But over the last few
weeks there has been an increasing pulsation on stopping. Tried pulling
the E-brake lightly while moving and there was no pulsation so I assume
that the issue is in the front still. If it is not a suspension problem,
it may be that the rotors have warped somewhat. The pulsation seems to be
minimal at first and gets more pronounced with successive stops. Seems to
bear out warpage. Anybody encounter this before? Afik, these are factory
stock rotors.
Oppie

Did you retorque the wheel nuts 30-50 miles after they did the work? I used
to on my 97SL2 and there was always a loose nut or two... (gee, am I
setting myself up or what?!?!)

 

[Oppie]

Did you retorque the wheel nuts 30-50 miles after they did the work? I used
to on my 97SL2 and there was always a loose nut or two... (gee, am I
setting myself up or what?!?!)

Will look into it. Thanks all.
Normally I would have done the brake job myself but was squeezed for time
and the state inspection was due shortly. Certainly not happy about the
pulsation especially after shelling out $300 for just the brake job. Will
drop by Saturn and have a talk with the service writer then take it from
there.

Really been racking up the miles lately. My daughter was in the hospital and
my wife and I have been running back and forth to her house (65 miles each
way) to help care for her family. Daughter was released on Monday after 10
days in the hospital for a bleeding problem and is now doing well. After all
the years of donating blood, this was the first time that I really felt I
got a return on 'investment'. If any of you are of a mind to donate also, it
would be greatly appreciated.
Thanks,
Oppie (O+)

 

[blue_x21]

My '97 SW2 had pulsing brakes soon after I bought it new.. The
dealership had to replace the rotors (under warranty) because turning
them down reduced the thickness unacceptably.
MY '01 SW2 pulsed a little, but not enough for me to get it fixed.

You should get Saturn to fix it for you. It won't go away on its own.

 

[Oppie]

I've been reading the shop manual to try to familiarize myself with the
layout before getting my hads dirty. I have never seen this before. The
E-Brake is a separate drum brake that is within the hub of the rear rotor (4
wheel disc). So much for pulling the E-brake to distinguish a rear brakes
problem from a front brake problem. On every other car I worked on, the
E-brake operated a cam that pushed on the regular service brakes. This is
the first car with ABS that I worked on so guess that accounts for some of
the differences.

Now will have to get the whole car up on jack stands, puill the wheels and
check all 4 rotors for warpage. Good news is that bleeding the brake system
does not need a diagnostic tool as is needed on some other vehicles.

Have I mentioned that the L series factory service manual is one step above
sh_t? Every other manual I have used gives a fairly good overview of the
systems included in that section. Diagrams usually had circles and arrows
with descriptions. Ths L series manuals have none of that and don't even
have a freaking index. There is some useful information but finding it and
trying to understand it from a picture (even for a seasoned tech/engineer
like me) is difficult.

Oppie