1996 gmc jimmy started making noise sounding like it is is right front was told need to replace wheel hub which was done. Still making the same noise in 2 wheel drive. when you push button for 4 wheel drive it stop making the noise but vehicle is not going into 4 wheel drive.

Bad bearings in the front differential.

If the problem is at the wheel, two possible causes are a bad wheel bearing or worn brake pads. Both of these noises will only be experienced with the vehicle on the ground and moving. Also, if this is a FWD truck and it only occurs when accelerating, it can also be caused by a failing drive axle or bad transfer case bearing.

Check everything in that right front driveline. Could have a problem that when the four wheel drive puts some tension on it, it stops making noise.

bad cv on passenger axel shaft if it has IFS if it has solid axle check the axle joint

There are ABS wheel speed sensors on the front wheels behind the hubs. It is possible if the hub where replaced either the pick up ring mounted to the hub itself was not installed or might have purchase non abs hubs or they just did not switch the wheel speed pickup ring on the new hub. Another thing could be either the wheel speed sensors are mis adjusted or when they replaced the hubs they hung the spindle by the abs wire and either pulled it out of socket or messed up the wires internally. Here is a basic abs system http://www.ehow.com/how_8511860_diagnose-abs-brakes.html if you have any other questions please let me know. Also please leave good feedback.

Hello mmcary: My name is Roger and I will help with your question. If you are standing in front of the van looking at the engine? The upper right hand pulley should be the air conditioner clutch and hub assembly. This is replaceable. If all that is bad is the clutch you do not need to replace the whole compressor. Should you need further help please just ask. Please rate the answer. Thank You for using Fix Ya. Roger

can you feel a vibration in the pedal when it is making the noise? Does it sound like the ABS engaging? If so you have a problem commonly referred to as overactive ABS. It is usually cuased by a wheel speed sensor dropping out at slow speeds. GM released a TSB on this that basically says to remove the speed sensors from the front hub/bearing assemblies (be careful when you do this if you break them off in the hub assemblies you will need to replace the entire hub/bearing assembly). Once removed clean the mounting surface in between the hub and sensor so that is free of any rust/debris. Then apply a thin coat of di-electric grease to the area and reinstall the sensors.

The other option is use a higher end scan tool to watch wheel speed data. Whatever wheel drops off first is the one you want to focus on.

I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa

It is a hub assembly, each wheel has one. If you have play, are getting a roaring noise, or have an ABS light on, these are all symptoms of a bad bearing.

If noise will go away when you turn wheels a different dirrection you need a wheel brg. hub assem.

Check the condition of the sway bar bushings.