Noise under driver's floorboard

[jtfannin]

I have a 93 xlt 4wd. I have noticed that when I start the vehicle and pull out of my driveway and pass maybe 5 or 10 mph, I hear a 'whirring noise' kind of like a small motor, for about 2 or 3 seconds. It sounds like it is coming from under the floor under my left foot. The other day, my abs kicked on on a wet bridge expansion joint, and once I stopped and then pulled out again, I heard it then, though it doesn't usually do it during stop and go, but only when pulling out in drive after starting it. Anyone know what this sound is?

Thanks for your help, Jason.

 

[X24]

Is it kinda a grinding noise sorta? Your transfer case is right below your feet. Could be your auto hubs crapping out.

 

[jtfannin]

Too consistent

Thanks, but I think the noise is too consistent to be something going bad on me. I have noticed that the 'motor noise' happens only when pulling out in drive after starting the vehicle once I hit 10 mph. It lasts for 1.5 - 2 seconds. I have no other driveability problems at all with the vehicle. I just bought it a month ago, and can't remember if it has always made this type of noise or not.

 

[ld50]

Mine did the same thing (I think). the ABS pump was coming on. If your ABS light is also coming on, I would seriously make sure your front hubs are tight. I had a problem with my pass hub loosening, and as soon as it loosened a little, it messed with my ABS, usually starting from my parking spot with the wheels turned.
Since I fixed the loosening hub problem, my ABS has not malfunctioned once.

 

[jtfannin]

Maybe so...

I have noticed that my ABS light stays on once I start the vehicle for maybe 1-2 seconds longer than the other lights. It never comes on while driving. I also just had my front brakes completely redone (new rotors, pads, calipers, lines). How would I check the hubs for looseness? There is no vibration at any speed or anything like that. I did notice (as I stated in my first post) that the only time it has made the noise while driving is one time after my ABS kicked in. When I finally got stopped, and pulled out again, it made that 'whirring' spund. Thanks, Jason.

 

[ld50]

Actually. I guess the right terminology would be "spindle nuts"

Do you have auto hubs? I`m not sure how to take these apart.
If they are loose your wheel will move slightly if you grab it and shake it. The abs uses your rotor to send the signal, so if it is loose it will make it think it needs to activate. When mine went off I could feel it in the brake pedal too, and the light wouldn`t go out untill I turned off the truck and restarted. If you have manual hubs, the hubs slip right off when you have the tire off. The nuts are prone to loosening.

 

[tenikiwon]

I know my buddies Chevy Suburbans have always done this and was told that it's normal. It the ABS system starting up or setting up. That's what it sounds like to me.

Check the other things but if the system is working then I wouldn't worry about it.