Brakes

[Kirkes]

I have two ?'s.
1. I just went to get new brake pads for my truck. They asked me if it was a HD I said it's a 3500 I thought they were all HD's. So what is the differance between a 3500 & a 3500 HD?
2. The reason i'm replacing them is when I apply the brakes at a stop sign it chatters like the anti lock brakes would if they lost grip. Is this a sign of bad breaks or something else?
Thank in advance
Kirkster

[DmaxMaverick]

You may or may not have needed a brake job. If your ABS is chattering at low speeds, refer to the TSB on front wheel speed sensors. They are inside the hub, and can be cleaned with limited success, described in the bulletin. The sensor can be replaced, but the reluctor wheel is integrated with the hub ($$$). If you need to test a sensor, I have 2 from expired wheel hubs. It just so happens I will be going to Watsonville tomorrow, so we can meet on the way if you need one. I'll be going via 99N to 152W with 5'er in tow. Or, I can send it to you next monday. To my knowledge, you can't get them separate, and have to purchase the entire hub. If you need one, I'll give it to you, but I would like to keep the other for my own spare. It's not likely they've both failed. This problem is usually isolated to the "salt belt" (midwest/NE), and not common here in the valley. I have heard of only one problem locally, yours might be the second. Try pulling the ABS fuse and try a stop. The ABS lamp in the I/P will iluminate, but the brakes will work, only w/o ABS. If the chattering disappears, it is a sensor problem.

You have a 3500. NOT an HD. The 3500HD is a completely different animal, and has been replaced by the 4500+ series. If the parts guy sold you brake parts for a 2500HD, they are the same as yours.

The 3500HD is a GMT-400 series truck (88-98 M/Y) with a GVWR of ~15K and 19.5" wheels. Popular for tow trucks, light engine fire trucks, utility company service, etc. The 3500HD was discontinued in 2002 or 2003. They are easy to ID, as they are lifted about 4" with an additional grill plate between the standard grill and bumper. They were only available as a chassis/cab, so if you see one with a pickup bed, it's been added. Nice trucks. Too bad they didn't continue the line.

[Kirkes]

Thanks for the reply
I leave real early to go to work so meeting up with you is realy not an option. So if you would mail it to me that would be great. I will pay for postage. I will email you my address at the email address in your Signature.
Thanks

[killerbee]

a little off topic DMaxMaverick. Will my brakes work better if they are recalibrated? I have 34.5" tires.

Can you explain? This has always bugged me.

[DmaxMaverick]

a little off topic DMaxMaverick. Will my brakes work better if they are recalibrated? I have 34.5" tires.

Can you explain? This has always bugged me.

I don't think so. The ABS is a very straight forward system. As long as the front and rear tires are the same size, it should work fine. Your low speed activation/deactivation speed may be effected, due to the actual rolling speed, but they will not be "improved" by calibration. The dealer or anyone with a Tech II can reprogram the ABS according to final drive ratio (tire size). A problem does come up if you change the diff gear ratio, as there is no option other than 3.73 with a Duramax, and changing the diff ratio will create a sensor input differential. Your tire rollout is about 12% offset from OEM, so I don't think you'll gain/lose noticeable ABS function at low speed by recalibrating. Recalibrating the speedo (such as with a programmer) will not effect the ABS tables. If you have an option to get it done for free, I say go for it. If I wanted it, and it cost me anything, I'd pass.

[killerbee]

Thanks!

That is pretty much what I thought. But I had read other stories of improvement, and it didn't make much sense to me. We'll see if there is someone who has a different explanation.

[DmaxMaverick]

Just a note:

I've taken interest in this for a couple reasons.

Kirkes' truck should not be experiencing the sensor failure, as happens with trucks in areas where road salt is used (reluctor wheel corrosion). Sensors can and do fail, so if this is the case, we may have a very cost effective solution. I am not aware of any availability of the sensor w/o the complete hub assy. The hubs cost ~$300 GM retail. Many of us have replaced the hubs for bearing failures, which leaves us with extra wheel speed sensors that should still be good. If these sensors can be successfully swapped from hub to hub, the solution would be nearly a free one. I've wondered how many hubs have been replaced for sensor problems, with good bearings. We'll let you know how it turns out.

[Kirkes]

[SIZE=3][FONT=Times New Roman]Here is a quick update. Pulled the ABS fuse like Dmaxmaverick suggested to do, & the clattering stopped so I

[Kirkes]

Do you think they might do this recall in Ca.
Thanks
NHTSA Campaign ID Number: 05V379000 - Hide Details (javascript:SwitchView( '29647');)
Recall Data: 08/29/2005
Components: SERVICE BRAKES, HYDRAULIC:ANTILOCK
Units Affected: 1353718

2002 GMC SIERRA SERVICE BRAKES (http://www.internetautoguide.com/auto-recalls/67-int/2002/gmc/sierra/3500/index.html#), HYDRAULIC:ANTILOCK
Recall Date: 08/29/2005

Summary:
CERTAIN PICKUP TRUCKS AND SPORT UTILITY VEHICLES MAY EXPERIENCE UNWANTED ANTILOCK BRAKE SYSTEM (ABS) ACTIVATION. THIS CONDITION IS MORE LIKELY TO OCCUR IN ENVIRONMENTALLY CORROSIVE AREAS. THIS RECALL WILL BE LAUNCHED IN THE "SALT BELT" STATES OF CONNECTICUT, DELAWARE, ILLINOIS, INDIANA, IOWA, MARYLAND, MASSACHUSETTS, MAINE, MICHIGAN, MINNESOTA, MISSOURI, NEW HAMPSHIRE, NEW JERSEY, NEW YORK, OHIO, PENNSYLVANIA, RHODE ISLAND, VERMONT, WEST VIRGINIA, WISCONSIN AND THE DISTRICT OF COLUMBIA ONLY.

Consequence:
THIS CAN CAUSE INCREASED STOPPING DISTANCES DURING LOW-SPEED BRAKE APPLICATIONS, WHICH COULD RESULT IN A CRASH.

Remedy:
DEALERS ARE TO REMOVE THE WHEEL SPEED SENSOR AND THOROUGHLY CLEAN THE WHEEL SPEED SENSOR MOUNTING SURFACE ON THE BEARING, APPLY RUST INHIBITOR TO THE CLEANED SURFACE, GREASE THE MOUNTING SURFACE, REINSTALL THE WHEEL SPEED SENSOR, AND CHECK THE PEAK-TO-PEAK OUTPUT VOLTAGE TO ENSURE THE WHEEL SPEED SIGNAL IS WITHIN SPECIFICATIONS. THE RECALL BEGAN SEPTEMBER 22, 2005. OWNERS MAY CONTACT CHEVROLET AT 1-800-630-2438 OR GMC AT 1-866-996-9463.

Potential Units Affected: 1353718

Notes: GMC SIERRA 05068

[DmaxMaverick]

They should. It may be out of the ordinary due to your location, but the issue is real, and can happen anywhere you drive. They only state it is "more likely to occur" in the salt belt states, but do not exclude other states. If you can show your issue is the same as what they describe, the bulletin would apply to your truck. If you are out of warranty, or they deny a claim, there's no reason you can't perform the procedure yourself. The drawback is if it doesn't fix it, the hubs need to be replaced. Hopefully cleaning it will do the trick. Still, don't rule out a faulty sensor, which is not covered by the TSB, and would fall under normal warranty (which is expired, unless you have an extended). Also, I don't know if the TSB will cover this if the truck is out of warranty.

[Kirkes]

Thanks DmaxMaverick
Maybe I will call the number that it there & see what they say.
I was hopeing that maybe this TSB would take care of it. It looks like more of a job than I want to tackle. Guess I will have to get a repair manual & dig in.
Thanks again
Kirkster

[DmaxMaverick]

Thanks DmaxMaverick
......Guess I will have to get a repair manual & dig in.
Thanks again
Kirkster

www.alldatadiy.com

Best manual you'll find anywhere.

[Kirkes]

Since my last post I developed a vibration. I’ve been talking with Dmaxmaverick A very nice, Very helpful guy. And with his help I determined that it is a bearing problem & that is what was making the speed sensor make the ABS act up. So I replaced the Right front hub & like most of you have all ready read it comes with new speed sensor new bearings. What it doesn’t come with is the nut that holds it on. Don’t wait tell the last minute to try to find one of these because not all dealer ships have them I was lucky and found one in Stockton about 20 miles away luckily there parts dept. was open till 7:00 pm and that gave me time to get there.
Dmaxmaverick told me you would need a impact wrench or a line backer. Well the impact wouldn’t do the job so I had to get my line backer son to take off the caliper bracket bolts. Any way job is done everything seems to be working fine.
Front hub & Lock tight from CARQUEST $276.00
Hub nut from dealer $ 3.79
Puller $12.00
Time 2 hours
Thanks to everyone
Kirkster