front end problem

[Knox5.0]

I have a 98 explorer XLT AWD. This is the first AWD vehicle i have ever owned so im not sure how much of the problem could be normal. When driving in a straight line everything seems completely normal except for a whinning noise at low speeds. However, if i turn the wheel left or right while driving i can feel an intermitten vibration through the steering wheel and driver seat. Theres not much of a noise but you can definetly feel it. It kinda feels like something could be grinding or binding. Also it seems like the harder you turn the wheel the worse it is. Anyone have an idea to what this could be? Axels? Differential? Power steering? It doesnt seem like a normal thing for the car to be doing. Im assuming it is something with the AWD. Otherwise the car drives great.

 

[my pos mounty]

No, it is not the way it is normally.

A whining noise/vibration in the front end is common though. It also has many causes. The wheel bearings/Hubs, front driveshaft being the most common. The front differential and the transfercase could also be the culprit.
You will need to investigate this further by getting the front of the truck up off the ground. STRONGLY suggest using jackstands.
1) Check the rubberboots on the CV/axles (inner and outer). If they are ripped and have spewed the grease out, they should be replaced.
2): Check bearing play, this is gonna take two, one to move the tire with a bar and the other watching your hub. Any movement in the bearing means its junk. This will also give you an Idea if the upper or lower balljoints are good or not.
3): Check the front driveshaft, give it a good shake. If it moves much, check the u-joint on the differential end of the driveshaft. If that is good, the CV end at the transfercase is junk. Replacement of the entire assembly is required. If you need one i strongly suggest sending a private message to a forum member by the name of ericautopart. You won't find a lower cost OE replacement shaft anywhere. (He is around $175 or so)
4): If you suspect the problem is within the transfercase, you could test the viscous coupling by removing the front driveshaft, drive the truck to a hill near you. Stop the truck and put in in park, but don't get out. If the truck "creeps" down the hill your coupling is good, if it doesn't...well you know.

Just so you know, (you might already) but it is very important that all 4 tires be exactly the same. Replace in sets of 4 only.
The viscous coupling in the transfercase makes up for small differences of rotational speed from the front to the rear of the truck, such as going around corners. If you have different sized tires, it will overheat/overwork the viscous coupling, essentially killing the transfercase.
Also that stress can overheat your front diff, rear diff, kill your front driveshaft, overstress and/or break the cv/axles, hubs, and u-joints on your rear driveshaft. Basically all turning parts beyond your transmission. Alot more expensive than a set of 4 tires.

Good luck and if you did not find the cause of your vibration, let us know

 

[Knox5.0]

Thanks for the reply. CV boots/axels are good. Doubtful its a wheel bearing. Since the problem only occurs when turning the wheel how would the driveshaft be a problem? Not saying it isnt but confused on how it could be since it stays stationary. Same for the transfer case. I could maybe see these as possibilities if the problem was occurring while going in a straight line as well.
I do know that my front diff has some seepage but not enough to leave a puddle or really any drips on the ground where i park. My shocks are also bad.
I should have been more specific in my original post about the vibration. When this problem occurs, it doesnt feel like your typical vibration. Its a little hard to describe in words but i guess its sorta like a rotational shutter that cuts in and out. Also, this is not a constant problem. It only happens on occasion and only when cutting the wheel while in motion. The only time i have felt anything similar was when driving a 4 wheel drive truck while in 4 wheel high on dry pavement and turning the wheel.

 

[my pos mounty]

Thanks for the reply. CV boots/axels are good. Doubtful its a wheel bearing. Since the problem only occurs when turning the wheel how would the driveshaft be a problem? Not saying it isnt but confused on how it could be since it stays stationary. Same for the transfer case. I could maybe see these as possibilities if the problem was occurring while going in a straight line as well.
I do know that my front diff has some seepage but not enough to leave a puddle or really any drips on the ground where i park. My shocks are also bad.
I should have been more specific in my original post about the vibration. When this problem occurs, it doesnt feel like your typical vibration. Its a little hard to describe in words but i guess its sorta like a rotational shutter that cuts in and out. Also, this is not a constant problem. It only happens on occasion and only when cutting the wheel while in motion. The only time i have felt anything similar was when driving a 4 wheel drive truck while in 4 wheel high on dry pavement and turning the wheel.

Why is it doubtful? When you turn the wheels either direction you are changing the stress put on the hub, thus changing and/or causing the noise. (I am playing devils advocate here, but after reading your entire answer... read on)
You say you feel it in the seat and thru the steering wheel, that typically points to driveshaft issues. Intermittent when different stresses are applied when going straight or turning, see previous post about viscous coupling.
By the way, your front driveshaft on your All Wheel Drive is never sitting still when the truck is in motion. If your moving, the front driveshaft is spinning. The AWD system is always on, unlike the Auto-4WD systems.
OK, if you feel a slight shudder when accelerating from a stop, with the wheels turned, it could be the Limited Slip clutches chattering. Look on your drivers door, theres a label. Look on that for the axle code, if it is a D1, D4, or D5 you have limited slip. You MIGHT get away with adding some more friction modifier to it, but that rarely works. Only way to be 100% sure to be rid of it would be replace the clutch packs.
Hope this has been helpful

 

[Knox5.0]

Why is it doubtful? When you turn the wheels either direction you are changing the stress put on the hub, thus changing and/or causing the noise. (I am playing devils advocate here, but after reading your entire answer... read on)
You say you feel it in the seat and thru the seat and the steering wheel, that typically points to driveshaft issues. Intermittent when different stresses are applied when going straight or turning, see previous post about viscous coupling.
By the way, your front driveshaft on your All Wheel Drive is never sitting still when the truck is in motion. If your moving, the front driveshaft is spinning. The AWD system is always on, unlike the Auto-4WD systems.
OK, if you feel a slight shudder when accelerating from a stop, with the wheels turned, it could be the Limited Slip clutches chattering. Look on your drivers door, theres a label. Look on that for the axle code, if it is a D1, D4, or D5 you have limited slip. You MIGHT get away with adding some more friction modifier to it, but that rarely works. Only way to be 100% sure to be rid of it would be replace the clutch packs.
Hope this has been helpful

I say doubtful on a wheel bearing cause there is no roaring noise associated. But doubtful doesnt mean 100% its not. When i said the driveshaft is stationary i meant in terms of it doesnt move side to side with the wheels when they turn. I know a driveshaft spins. The limited slip could be a possibility. I didnt think of that. I would think it has to be a component that moves with the wheels since the problem occurs only when the wheels are turned. I feel like the driveshaft would be felt regardless of what direction the wheels are in. Same for the transfer case. Its probably a wheel bearing or one of the axels or possibly something funny with the front diff. Thanks for your replies though, theyve given me more ideas on possible causes.

 

[my pos mounty]

If it is a light shudder, very evident when starting from a stop with wheels turned at least moderately, my money would go on Limited Slip Clutch packs. I cant really explain the sensation other than to say that it kinda feels like when I was younger and went to hard-rock concerts and got close to the speakers and the drummer went crazy. Your whole body shakes, that is kind of the sensation, but without that noise level. Real quick vibrating sensation...if that all makes sense???

Anyone else want to chime in on this with any information I might have left out that your aware of?

 

[jds3403]

I have a similar situation, when traveling at maybe ten mph or above and performing a relatively sharp turn I get a shudder in the steering wheel which is brief and only happens while engaging the steering system. If I took off from a stop with the wheels turned I dont get any feedback, so for me it is not the rear end, (I have a limited slip). Also I have replaced almost all the front end components, (b. joints, tie rod ends, shocks,) and I did a 4406 swap with a AVM hub swap as well, so I replaced the hubs, cv shafts and replcased the braking system as well (rotors, pads remaned calipers).... The reason I say this is because my front end is disengaged, the wheels are the only thing that turn, no cv shaft or or diff. This has been easy for troubleshooting, eliminates the front drive system (cv shafts, diff etc...) and since the shudder only happens while turning the wheel, I am fairly certain it is coming from the steering system. I have bled the system in the past with new fluid over a year ago and this problem is fairly new, so I know there arent any air issues, also the pump is not whining and the steering does work so the pump is atleast working, engine rpm's dont seem to affect the problem either so I have ruled out the pump, I unfortunately think my rack is fixing to **** the bed....

just my 2cents

ps running 32x11.5x15 BFG's on american racing 15x8's....... never helps