New 2500HD Owner & Questions

[disneyd]

Greetings everyone!

 

I recently bought a 2001 2500HD 4WD with the 8.1 Vortec and Allison transmission. With 109k, the truck seems to be in really good shape, but I have several issues I want to fix.

 

The first is the random ABS/Brake light issue. From what I can tell, I need to pull the ABS module and resolder the bad joints. It looks like it is a little tricky to get the unit open, but once I'm in there I don't expect any trouble (I have an electronics background). However, any pointers you guys can throw out would be appreciated.

 

I also have some steering play and vibration to track down.

 

Any common reliability/maintenance issues I should look into?

 

My actual question for this post is about the power mirrors. I replaced the driver's door mirror switch with a new one and regained about half the mirror function I was missing, but both mirrors still don't function in all directions. Is there a common cause of this after the mirror switch? Are the motors known to fail, wiring issues, etc.?

 

Thanks

[newdude]

Wheel speed sensor mounting surface corrosion is a very common issue on those body style trucks. Rust gets under where the sensor sits on the wheel bearings and will raise the sensor up if you will causing an air gap and then ABS lights or ABS activation at low speeds during stops.

 

Also, another common deal is corrosion failure of the ABS module. They get water, salt, etc. in them and swell up and rot from the inside out. The screws that hold it down don't always separate from the ABS valve and then you end up replacing both pieces.

 

As for the mirrors, you could have issues with the mirror motors themselves which on a 16 year old truck, isn't out of the realm of possibility. Did you put a GM or aftermarket switch in?

[dewfpo]

If they're the power extending tow mirrors and the power extend doesn't work I found that if they aren't moved very often they stop working but if I play with the button for 15 or 20 times in a row it will eventually resume operation. It's almost like without use, some corrosion or something builds up then playing with the switch removes it and they start working again.

 

DEWFPO

[disneyd]

Thanks. I'll check the wheel speed sensors first. The ABS module looks pretty clean from the outside, so hopefully it isn't in too bad shape. I wish it wasn't down there on the frame rail... not the best place for electronics.

 

It was a Dorman switch. Are they know to be questionable? I'll check the continuity on all the contacts before I dig into the mirrors themselves. I would have just taken the original switch apart and cleaned/checked it, but the Dorman switch was only $20.

Thanks. I'll check the wheel speed sensors first. The ABS module looks pretty clean from the outside, so hopefully it isn't in too bad shape. I wish it wasn't down there on the frame rail... not the best place for electronics.

 

It was a Dorman switch. Are they know to be questionable? I'll check the continuity on all the contacts before I dig into the mirrors themselves. I would have just taken the original switch apart and cleaned/checked it, but the Dorman switch was only $20.

[disneyd]

Thanks Dewfpo. These aren't power extending though, they're manual extending but power left,right,up,down.

[davester]

It's also common for the ground for the ABS computer to not be reliable, which also causes random abs failures (sometimes it generates a code/turns on the dash lights, sometimes not).

 

Under the drivers side door, there's a "wing" off the frame which some grounds bolt to. Unbolt them, clean off the frame there and the eyelets, maybe put on a dab of dielectric grease, and bolt them back down.

 

This fixed my problem of the abs/brake lights and the 'service brakes soon' message being displayed intermittently with my truck.

[disneyd]

It's also common for the ground for the ABS computer to not be reliable, which also causes random abs failures (sometimes it generates a code/turns on the dash lights, sometimes not).

 

Under the drivers side door, there's a "wing" off the frame which some grounds bolt to. Unbolt them, clean off the frame there and the eyelets, maybe put on a dab of dielectric grease, and bolt them back down.

 

This fixed my problem of the abs/brake lights and the 'service brakes soon' message being displayed intermittently with my truck.

 

Thanks! That's exactly the sort of info I'm looking for.