Hey everyone... Just got a 01 1500 Sport QuadCab. I noticed that when I am driving at high speeds (over 63 mph) there is a vibration/light grinding kinda sound coming from the front drivers side area. The faster I go the louder it is. If I am going 63-65 and let off the gas you hear it for a second. If i am going 65+ it a steady sound. Also when it is in 4wd no matter what speed I am going when I hit the throttle you will always hear the sound.

The person that I got it from said that they did both wheel bearing/hubs 6 months ago at the same time.

When I jack the front end up in the air both passenger and drivers wheels will move slightly from side to side with a kinda thunking sound. They do not move when moving the top and bottom of the tire.

Any help will be greatly appreciated!!

Thanks!!

 

could it be the squealer tabs on the brake pads? if you touch the brakes very lightly, does the sound go away? check the thickness of the brake pads.

wheel bearings would make a roaring sound. your noise doesn't fit that, and i'd expect wheel bearings to last a lot longer than 6 mo. also, you'd have top/bottom play in the tire/wheel.

 

I havent noticed if that happens or not when i touch the brakes. I will have to pay closer attention next time I am out.

Yeah, there is side to side play on both wheels but not top to bottom play at all. I am going to inspect the squealer tabs on them. But when i am going 63-65 and let off the throttle, it sounds like when you try to engage a gear thats not all the way engaged. but the sound isnt a loud grind, its a very light grind sound or vidration that sounds like a soft grinding.

Hard to explain, just don want to goto the dealer if its something simple.

 

could it be the stupid cad collar touching the inner axle? i'd think it would do it at all speeds.

there shouldn't be any side to side play, but - there are a lot of moving steering parts in that direction including tie rod ends, etc. none of those would be associated with a speed pitched grinding.

 

What is the Cad Collar and how do I check it or fix it?

 

see here for a description of the CAD.
http://dodgeram.org/tech/repair/4X4/4x4_engagment.htm

the passenger side front axle is two pieces, which couple together at the CAD box, about halfway across the passenger side axle tube.
a splined collar stays permanently on the outer axle, and slides over about 1 inch to engage the inner axle. this engagement is triggered by a vacuum signal when you shift the tcase to 4wd.
proper vacuum signal is to pull the collar off the inner axle for 2wd and push it onto the inner axle for 4wd.
the outer half of the axle is rotating full time.
the inner half only rotates when in 4wd.
if you have weak or no vac signal, the collar can sort of float around and strike the inner axle and make a terrible grinding sound under the passenger floorboard.

 

great... I am going to check it out on the truck. Only thing is that the noise is coming more from the drivers side area of the vehicle.

 

cad was just something to consider. if it was the cause of the sound, its clearly on the passenger side.

jack up the front end and rotate everything by hand. see if you can duplicate the sound or pick up on a bad feeling.

 

Well I just crawled under there and noticed that there is a electrical harness that connects into the CAD. It was not plugged in all the way. But that I believe goes to the indicator lamp on the dash. That has not been on while the vehicle is in 4wd nor does it come on when you turn the key forward before starting during the guage check. (bulb out???)

The 4wd has been working however.

I have truned everything by hand and could not duplicate the sound. It is only at high speeds in 2wd and when the vehicle is being accelerated in 4wd.

 

There is a electrical wire harness that plugs into the axle right there at the CAD. I just crawled under there and noticed that the harness was not plugged in all the way. Could that effect anything? 4wd has been working. What does that harness do?


the electrical connector is on the drivers side of the cad area. its only purpose is to turn the 4wd light in the dash on and off. it doesn't do anything else. the operation of the cad is all vacuum controlled