well im thinking its something else causing the vibration and noise, i did a pretty nice burnout earlier leaving a puddle of water and just the rear spun so...

 

Seems like you treat it nice enough, I can't imagine why it would make funny noises.

 

you know a easier way to see if all 4 wheels are getting power??

 

Lighten up Pal. I guess I'm lost on how doing a burn out proves all 4 wheels are getting power?

 

This just means your front axle isn't engaged. The front driveshaft could still be engaged, turning, and causing the noise.

 

"Lighten up Pal" - I was simply responding to what i thought was a smart *** comment saying i dont take care of my vehicles by doing a burnout which didnt make any sense . If i didnt care about my truck i wouldnt be worried about the noise its making and just run it into the ground,lol! doing the burnout and only having the rear wheels spin makes me believe its not in 4wd like i thought it was because if it was i doubt i would of lost traction at all or would of had the front spinning as well





"This just means your front axle isn't engaged. The front driveshaft could still be engaged, turning, and causing the noise"

if the front drive shaft was still engaged wouldnt it try to assist the front wheels when losing traction?

 

Only if your switch was in A4WD, but not if it was in 2WDH. If you're in 2WDH but the shift motor is stuck in 4-wheel, then there is never a signal sent to lock up the front axle and provide power to the wheels even though the front driveshaft is powered.

 

i was switching it back and forth a lil while ago with the truck off but key on, from 2wd to awd i just hear a faint click sound coming from the center of the dash it sounds and only way to hear it is with the truck off and no radio, from awd to 4wd theres a very noticeable clunking sound from under the truck same from 4wd to 4L, if the motor was stuck would i still be hearing these sounds when engaging the 4wd? and were exactly is this motor?

 

Automatic 4 wheel drive will not make any sound when switching it. As the name implies it will stay in 2 wheel unless there is a slip of the rear wheels where they are going at a different speed than the front, then it will automaticaly shift into 4 wheel drive. When you did the burn out were you in 2 wheel drive or in automatic 4 wheel. If you were in automatic 4 wheel then you have a problem. As stated earlier it could be the shift motor number 1, number two it could be the vaccuum switch for the front axle depending on the year I think it is 97 & 98, I know my 99 does not have a vaccuum switch for the front axle. Another thing to check out if it is the switch for the front axle is the vaccuum hose that runs behind the battery, they seem to get holes in them causing problems with the switch.

 

no i was in 2wd when i did the burnout, were is the vac switch located on the 97?

 

If the light is not on the shift motor is NOT stuck in 4WD. The light is lit by contacts inside the motor. The front actuator MAY have the front axle engaged which makes the whine but no dash light. Check the vacuum at the front axle (top right of the diff behind the black cover) it uses vacuum to engage on one port and vacuum to disengage on the other port. Controlled by solenoids behind the battery

 

87wreckerman, did you ever sort this out? I am having a similar occurence with a 97 EB Expy. Slight noise in reverse only from somewhere up front. Just discovered last night that I have no drive to the front axle in A4WD or 4WD. Confirmed this in Low Range tonight, Transfer Case shifted, but no pull from the front end. I plan to check out the vacuum motor. Just wanted to follow up and get ideas from others