The Dutch Man

I brought my 03 in today for an oil change and few other things. My brakes have been pulsing and it's driving me nuts. So, the dealer drove it twice and agreed. They put brand new rotors on but used the same original pads over again. Braking now is much better, however, I still feel that slight pulse in the pedal. Is this due to the brake pads not being totally flat from the old warped rotors? Will they flatten out to conform to the brand new rotors? I hate to bring the truck in again regarding this but it's driving me nutty. I can't believe they replaced the rotors and not the pads. Whenever I've replaced rotors, I've always done the pads. Argh! Fustrating!

Dutchman

TechWrench

I would agree that they should have changed the pads too, but I doubt they are the cause of the pulse. Either the rotors are defective, they weren't mounted properly, or they over torqued the wheels and they are causing the rotors to warp. In either case, I would take it back to them.

bulldog-yota

Did they only replace the front rotors? Or front and rear rotors? The pads should not cause pulsating, but it is always good practice to replace it with the rotors. Did the ABS system check out fine?

How many miles have you done?

The Dutch Man

Hey Guys,

Picked the truck up last night. First thing I did last night was loosen and retorque the front lugs to 85 ft. lbs. They only replaced the front rotors and not the rears. A more accurate description of the pulse is only when light braking. Basically lightly touching the pedal you feel a slight vibration. Getting off the highway this AM I was slowing down and as soon as I start really applying the brakes, the pulsation goes away and braking is now smooth. It's this slight pulse that's bothering me. I can't stand it! I know others have mentioned the same here in other posts. The dealer is starting to think I'm crazy. I haven't called them again this morning. I'm debating what to do. I'm starting to think that maybe it's just the way the master cylinder and all the crazy smart braking systems operate. I did notice this morning that parked in the parking lot, if I press the brake 4-5 seperate times, I hear the buzz of the motor for the master cylinder coming on. Is this normal?

aowRS

Dutchman,
I have a feeling you will continue to be plagued by this. I have had front brake pulsation on my '01 since the first few months of use. I purchased the truck new in June of 2001 and now have 73,500 miles on the original brakes - front and rear. Mine will exhibit the same frustrating signs - a light pulsation when the brakes are lightly applied, but then it seems to disappear as you press harder to actually stop. Now coming down a mountain grade is an entirely different book. It will actually get to the point where the front brakes pulsate so bad that I simply downshift to give them a rest. I never thought I'd say this, but I've learned to live with it. I love so much about my 4Runner that I'm willing to somewhat overlook its metallurgical deficiencies....

Now if a company brings out a replacement front rotor that is guaranteed to be warp free for life - I'll buy it. I think wheel nut torquing certainly has something to do with it, but I've also heard that there are issues with heat transfer between the various hub & brake components. Seems like this issue has become far more prevalent in the last 10 - 15 years though. What's bizarre is how diffferent the brakes acted on my '91 Escort GT. This was also a new car purchase that I eventually logged 233,000 miles on in 9 years. At the 170,000 mile mark I replaced the front rotors. Not because of pulsation, but because of how paper thin I had worn them with repeated late braking... I used those brakes hard, all of the time, and never once did they exhibit any signs of pulsation. Stange, huh?

I take great pains to keep my truck in new condition, mechanically as well as cosmetically, but I will not allow the brake pulsation issue to cost me sleep. I certainly will not take it to a dealer for this. When the time comes for new brakes, I'll swap in new parts. Turning the front rotors will only take care of the problem for a short time.

Hope that helps.

Andreas

The Dutch Man

I appreciate the comments and feel better that other people are experienceing the same problem. What you described about is exactly the feeling I get through my pedal. Now why the pulse is still there a day after putting new rotors on is beyond me. I can say that the ding dong dealer did have a couple of the lugs tourqed beyond belief. Had to bring out the big breaker bar last night so I could retourqe them. I can also say that the problem gets worse as I drive longer distances and the rotors heat up. I'm interest to hear other 03 or 04 owners chime in and see what they say. I don't know what to do about this. Is it just the way this truck is or is their a deeper problem like the master cylinder malfunction. I can say that no lights have ever come on the dash so I'm ruling out the master cylinder for the most part. I love this truck, it's the best I ever owned (next to my 88 Toyota Camry). If I could only get past this problem!

bulldog-yota

My 03 4Runner sometimes have a very very soft buzzing sound from the left of the steering wheel towards the front (I assume it is the brake system by the master cylinder). Normally just after start up and the first mile or so I drive. DOnt really notice it unless I specifically listen for it. Once I start driving I have not really heard it. My brakes are fine with no pulsating, and notice no difference when driving and it heats up.

I would keep taking it back to the dealer till they fix it, as it might have to do with any of the fancy electronics on the braking system. As we now have ATRAC, VSC, ABS and EBD, oh I forgot HSA and HDC, God knows what else, all using the braking system and sensors.

It is actually funny as the 4Runner looks like a simple SUV, but I started thinking about all the electronics on the mechanical side. First the braking system has a zillion electronic features to the point where pressing the brake pedal is just a suggestion to the computer these days, the starter is electrnic controlled, the throttle drive by wire, the gearbox, obviously all the engine mechanisms. Fortunately the wheels still turn mechanically

ruizs

I'm guessing it is over-torque-ing of the lugnuts. Most shops just throw them on with an impact wrench, which can screw up brand new rotors even one time. I just put on new rotors, torqued the wheels correctly, and don't have a pulse.
I don't trust a shop to do repairs like these, they just try to get it done as quick as possible. If you have a jack, and a metric ratchet set, you can do this yourself. In my opinion, its the easiest thing next to an oil change, takes me about 30/40 minutes.

The Dutch Man

Ruizs. The first thing I did after getting home last night was loosen the lugs and retouqe the rotors. I only drove a max. of 20 miles on the rotors. Looks like I'm complaining again when my truck goes in for the new Cat Conv per the latest TSB. Will the pulse possibly go away with normal wear?

TechWrench

Just a thought, but maybe the problem is with the rear rotors? As for the heat issue, I worked for a Honda dealer for several years, and they used to have all sorts of brake rotor problems. One of the big ones was the weather in the Northeast. If you worked the brakes hard and then ran thru a puddle of cold water/ice/slush the rotors would often warp right then. Another problem was inconsistant density in the metal. We had brand new rotors which pulsed because of 'hard' spots. I remember changing some sets two or three times before we got a good set. As for my '03, knock on wood, no brake problems yet.

tom4416

I'd mention to the dealer the issue about improper torque on the lug nuts. One time is all it takes and as soon as they get a little heated up, warpage. I make sure that any service ticket concerning removal of the wheels have the legend "hand torque only" and then watch them like a hawk. Before I did this, I had several rotors tore up on cars because of the heavy handed technician. Since then, never a problem with a rotor. I hand torqued my own lug nuts in the dealers parking lot when I picked up my new truck befor it had 5 miles on it. They were at least close from the factory.

The Dutch Man

Guys, thanks for the input. I'm going to mention the brake problem again when bringing the truck to the dealer for the cat conv. It could possiblly be the rear rotors as well. Don't know? Will have them check it out. The advice on the service ticket is good, however, upon the last service I had the service writer put down "do not rotate or balance the tires." Guess what, my tires were balanced and rotated when I got to the dealer. Glad to see that they pay attention to the service ticket. Freakin dealers!

Flamedx4

[Now if a company brings out a replacement front rotor that is guaranteed to be warp free for life - I'll buy it.]

LOL, I hear ya, but it's not possible to make a rotor that cannot warp, so if they guaranteed em for life they'd just be overcharging you to make up for the ones that come back...

There is no way any rotor can ever be immune to heat issues, after all converting inertia to heat and shedding it is what they do. The rotor has to accept a certain amount of heat (and shed it) at a certain rate, so no matter how good the metalurgy is, the potential for warpage has to exist. Too many variables, like the guy who always brakes late, or the guy who is so gentle on his brakes that the pads glaze up and rotor gets polished, or the guy who gets them red hot then drives through a stream, or the guy who uses his brakes going down long hills rather than downshift and save the brakes.... Look at carbon racing brakes - these can take astounding abuse and do not warp. But they don't work at all until they get hotter than you could ever get them on the street, so they aren't the answer. General use is a broader target.

HondaTec521

I agree w/ Techwrench,your rear brakes could be the problem.If you feel no vibe.in the steering wheel on braking it's possibly the rear.But you did mention overtorqued lug nuts(not good).I work next to several(limited english speaking)"mechanico's that HAMMER lug nuts on.Next time at the dealer request a ASE certified /Toyota cert. tech to work on your truck.
Pumping your brake pedal drains your Power booster of engine vacuum , so it's normal to hear some slight noise/idle rpm drop.

The Dutch Man

Well, Here's the verdict. I had the exhaust TSB done yesterday. Mentioned the brake and came back the dealer to find brand new rear rotors. Drove it home and my brakes are smooth as new. So, in the end it was the rear rotors that were warped. That's to all you guys for the help. I'm very happy now!

Dutchman

TechWrench

Glad to here you finally got the problem solved.