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mrhockey
01-03-2009, 19:22
I just had my 2003 2500 HD to the shop for inspection and all is well. The problem that didn't show up on a scanner or throw a code is when I am coming to a stop at normal speed, when the truck is almost stopped, the brake pedal fades and the steering wheel always pulls to the right. My mechanic hooked up a scanner and wheel speed sensor to the truck and the wheel speeds were identical on the front. He felt it doing it but no codes. Is it something with the abs sensors or something?

Mark Rinker
01-03-2009, 21:43
Hmmm...your brake boost and power steering are both hydraulic from your power steering pump...have you checked for fluid levels/leaks?

mrhockey
01-03-2009, 22:16
No but I will give it a check tomorrow. Thanks.

DmaxMaverick
01-03-2009, 22:21
Sounds like a failing master cylinder. As Mark said, check the PS and brake fluid levels first (the pump is usually noisy when it gets low, with intermittent brake and steering feel). If the pedal is fading (slowly goes to the floor), it is the MC. As more brake pedal input is applied, more fluid flow/pressure is demanded of the pump, taking away from the steering. There is a test procedure for this symptom posted in this forum. Try a search for "hydroboost", and it was posted by me. Let us know if you don't find it, and I'll dig it up.

rat4go
03-28-2009, 13:26
Sort of reviving an older post, but....I recently noticed the same thing (brake 'fade' just before a complete stop), but no steering wheel pulling. Brakes work great until the 'almost stopped' point, then I lose a small amount of stopping power requiring more pedal force. Pedal doesn't seem like it travels more, it just needs more force from my foot.

I'd say it's almost like the ABS is removing pressure, but there's no abs noise or other typical ABS type things going on.

I've recently done front brakes and put Bendix ceramic's on the front. I was almost wondering if they have different friction properties or something.

I've checked fluid levels recently as part of the PM I do at oil change time and no issues there.

Unlike the OP, I haven't put a scan tool on it to look for wheel speed sensor issues yet, but that's next.

JohnC
03-29-2009, 09:45
My bet is one wheel speed sensor is starting to go. If you live in a rust belt, like I do, where they use salt in an inch-for-inch relation to snow fall, the other one is not far behind.

The scanner will only see it when it's acting up, right before the stop.

rat4go
04-20-2009, 16:56
My bet is one wheel speed sensor is starting to go. If you live in a rust belt, like I do, where they use salt in an inch-for-inch relation to snow fall, the other one is not far behind.

The scanner will only see it when it's acting up, right before the stop.

+1 Had problem. Had it on scanner and no codes. Data display only showed issue if you recorded data. I found service bulletin saying that corrosion under sensor mounting face on hub can cause sensor to push 'out' a little bit and not read at slow speeds which causes abs to act funny. I broke my sensor trying to get it out, so I got to buy a new hub.

It fixed the brake problem, though.