I know this is a subject covered in many threads but I see these are almost completely 4X4 related when it comes to these two lights coming on.
Mine, as the title indicates is a 2X4 and these two lights came on about a week or so ago. They came on together right after I started the truck and they don't always stay on. When the lights are on I the brake pedal feels different. Maybe it's in my head???
I have an ACTRON scanner-cp9580 and it read a code "21" when I checked the ABS system and it said "front right ABS erratic sensor reading" or something like that. I don't know for certain that this reader is accurate for my trucks ABS because the scanner also asks me to get the brake/ABS software package when I hook it up and do an ABS scan. I did use it to erase the code but this lasted only a short time.
In reading several posts here I saw there were a lot of these front sensors going bad from the front hub(s) over heating but this is obviously not the same for a 2X4 vehicle UNLESS I misread something and the hubs being mentioned were for 2X4 as well.
Any help is greatly appreciated.

 

I could be wrong but I "Think" the front wheel hubs that have the sensor and sensor ring are the same on 4x4 as 4x2. They are internal. If so you can remove the sensor and visually inspect it and clean off the tip. But first I would check the wires for any damage.

 

Yes, the front wheel hubs do have a ABS sensor, the hubs are very similar to the 4x4 models. I believe the correct term is unitized hub wheel bearings. It is prob the wheel bearing going out and its changing the air gap from the sensor to the tone ring. No big deal. They are about $150 and include new sensor. Might look at your ball joints while you have It apart.

 

Thanks for the information. I have a FSM but can't get to it for another day. Are these hubs on the 2X4 different than other vehicles? When I hear the words front hub for a 2X4 I think of the rotor. Other than rear disks I've not seen a rotor without a "hub" as part of the rotor?
I did happen to notice the right upper ball joint boot is shot so I'll need to replace it soon anyway but this suggestion has nothing to do with the ball joint creating any issues with the ABS sensor correct? Sounds like it is a bearing (inner and outer) getting sloppy on the spindle. I suppose it is worth asking if the term "hub" is the same as what I call the spindle? I have 150k miles and I'm on the second set of brakes. Never have had the rotors off.
If the spindle (hub) is bad I'd have to ask *** is up with that? I've run vehicles from showroom to scrap yard without a single problem with spindles. Kind of a bad area to have chronic issues with IMO.
Thanks

 

The brake rotor slides over the studs and rests on the face of the "unitized hub bearing". So,
Remove wheel, remove caliper and bracket and pads, remove rotor from the hub.
there are 4 bolts on the back side of Hub bearing. Remove them and then remove unitized hub assembly.

 

I got lucky. I was going to take mine to the shop when my lights came on.
I decided to get it washed first including the undercarriage. After the wash everything was fine again.

 

Is there a way to check for play in the hub? I checked it by lifting the wheel and shaking it but I didn't feel any up/down movement?

 

If they are bad enough, yes. I replaced mine because I had a light vibration/growl, but had no movement in the wheel bearing its self. I had to take the tire, caliper, rotor off and turn hub by hand, then I could def feel the roughness of the bearings turning. It could also be, that you have a broken ABS wire or the connector is not completely connected. Seen both before. but in my experience it was a sign of wheel bearings starting to go.