Transfer Case Or Drive Shaft Problems.

I have a 97 Exploder Sport with Control-trac. I have been having a grinding, moaning, vibration type noise.
It sounds like it's coming from the left front (wheel bearing) but it feels like it coming from under my feet (drive shaft or transfer case).
It only happens when under load and goes away when coasting. So I don't think it's a wheel bearing. However it also goes away when I turn left under load. It is driving me freaking NUTS.
I have replaced:
Upper & lower ball joints (both sides)
New tires & wheel balance.
Alignment
So it is not any tire, balance, alignment or ball joint issue.
My feeling is it is a front drive shaft or bearing in the transfer case.
I want to try to eliminate the drive shaft as the potential problem. So my question is can I disconnect the drive shaft & drive it around without hurting anything?
Does anyone have any ideas on what this problem is? I'm about ready to push this P.O.S off a cliff.
HELP.

Yes you can pull the driveshaft out - but the load and torque will be taken away from the t-case which may get rid of your noise. I went through a similar problem and my t-case is in need of rebuild. My chain is the problem (atleast that's what 2 other techs said) - but I dont' think this is your problem as the noise is only with the driveshaft in and it is a scary sound

I was just thinking - you said it goes away when turning left? Well that is a good indication of wheel bearing issues. Try driving in a S pattern (safely) and see exactly when it goes away. If it does go away on left turns... your left wheel bearing may be the problem.

-Drew

I thought it was a wheel bearing too.....at first because it goes away when I turn left. But it also goes away when I let off the gas even if I'm turning right. Would a bearing only make noise under load? This noise goes away when I let off the gas. It is also much less noticable at high speed (above 60)...and I would think a wheel bearing would be louder at high speeds.
Like I said before it sounds like its coming from the front left side but FEELS like its coming from beneath my feet(front drive shaft or transfer case). The noise sounds like a rotational, groaning, bearing type noise.
I want to try to eliminate the front drive shaft as the source by taking it off to see if I still have the grinding, moaning noise. If the noise is still there after removing the drive shaft I would think it would be the transfer case.
Can I drive the vehicle with the front drive shaft out without causing any damage to the vehicle? How long can I drive it w/o a front drive shaft?
Is it possible that the bearings in the tranfer case are shot...if so can you replace the bearings?
I would appreciate any input anyone might have. It's driving me nuts.

Sometimes these can be difficult to accurately diagnose, but I'm with Drew that it's possibly a wheel bearing, or (and more likely in my opinion) your transfer case.

Could it possibly be a front u-joint? I did notice some play in the front u-joint.
I have never had one make this type of noise though.
I definately don't think its a wheel bearing cause the rotational noise it makes is much slower than the speed the wheels are rotating.
I hope it's not the tranfer case....what does a used t-case go for? Is it cheaper to rebuild or replace?
Sorry for all the questions but this is my first Exploder...all my other 4x4's have been pre 1980's.....and I've never had even close to the problems I've had with this P.O.S.
Thanks for your input though.

So anyway..can I run without a front drive shaft without causing problems?

Mine is a 97 limited 5.0 Awd. Bad noises were coming from under the my feet. I took off my front driveline last night and the CV where the driveline meets the transfer case, had no rubber seal left. There is just a flange on the t-case so no fluid leaks out, and the rig drives fine.

I bought this rig saturday and drove it 600 miles home so I think it over heated and blew out somewhere along the way. I find this to be an opportune time to check for posi in the rear end.

04Fatboy said:

So anyway..can I run without a front drive shaft without causing problems?

Click to expand...

On a Control-Trac A4WD system (that's you), Yes.

If it's a u-joint, it'll generally make the noise at the drive axle multiple of the wheel rotations, and it'll be rhythmic, not steady. (i.e. the noise will squeak three or four times for every wheel revolution) Halfshafts will make the noise either once or twice per wheel revolution, and wheel bearings can vary, but inevitably end up with a rumbling feeling that goes away when you swerve one direction and get louder in teh other (loads inner and outer baring alternately)

A few more questions to help us troubleshoot it:

Does the pitch vary with speed? (i.e. the faster you go, the higher the pitch)
Does the intensity of the sound vary with speed, or direction you're turning?
Is it a constant tone or more of a rhythmic pattern?
If you lock it in 4x4 high when traveling straight, does it make the noise any louder or quieter?

-Joe

Noise

Jack your vehicle up and put yout hands at 3 & 9 o'clock position and try to shake the tire/wheel. If you can detect movement then your steering/tie rod/idler arm need replacing. Now put your hands at 12 and 6 o'clock position and try the same test. If you detect any movement your wheel bearing is gone. How about your brakes, if you have a warped/worn out rotor or hanging cylinder, that could create the sound. If you know your universals are shot, replace them, everything adds up. Start where you know you have a problem and correct things one at a time.

Bill

gijoecam said:

On a Control-Trac A4WD system (that's you), Yes.

If it's a u-joint, it'll generally make the noise at the drive axle multiple of the wheel rotations, and it'll be rhythmic, not steady. (i.e. the noise will squeak three or four times for every wheel revolution) Halfshafts will make the noise either once or twice per wheel revolution, and wheel bearings can vary, but inevitably end up with a rumbling feeling that goes away when you swerve one direction and get louder in teh other (loads inner and outer baring alternately)

A few more questions to help us troubleshoot it:

Does the pitch vary with speed? (i.e. the faster you go, the higher the pitch)
Does the intensity of the sound vary with speed, or direction you're turning?
Is it a constant tone or more of a rhythmic pattern?
If you lock it in 4x4 high when traveling straight, does it make the noise any louder or quieter?

-Joe

Click to expand...

Pitch does not vary with speed.
It FEELS like its under my feet.
The intensity DOES vary with direction..turning left it goes away.
Coasting in Neutral goes away.
Let off the gas...it goes away after a second or two.
It only makes noise under load (on the gas)
It is a rhythmic type pattern.
I have not tried it in 4x4 high...but I will asap.

Thanks for your help

One more question..Do I need to disconnect any sensors when I take out the drive shaft.
I'm going to be driving it around for a while until I get new U-joints in and I don't want to scew anything up worse than it is.

Nope. With your t-case, you can pull either shaft and be fine. If you pull the front shaft, the system will just think you're driving on a very slippery surface for an extended period of time. Personally, I would flick the switch into 4 high just to lock up the t-case and eliminate any chance of over-cycling the Torque-On-Demand relay. I realize it's solid-state and all, but it's just me....

-Joe

Do you have auto, or manual hubs? Did you try locking, and unlocking them to see if the noise changed?

Well... I replaced both front Wheel Bearing/ Hub assembies this weekend (@ $157. each) and the NOISE is STILL there.
Someone HELP.

Glacier991 said:

Sometimes these can be difficult to accurately diagnose, but I'm with Drew that it's possibly a wheel bearing, or (and more likely in my opinion) your transfer case.

Click to expand...

What would you suggest to check in the tranfer case? This is really driving me crazy, I have spent over a $1000 trying to fix this noise and I'm obout tapped out and the noise remains.
Someone Help Please.

I'm still not sure why turning left would make the noise go away. That's the only symptom throwing me for a loop.

Have you checked for slop in the rear driveshaft? I'm thinking pinion bearing or transfer case output shaft slop? What about the u-joints?

-Joe

gijoecam said:

I'm still not sure why turning left would make the noise go away. That's the only symptom throwing me for a loop.

Have you checked for slop in the rear driveshaft? I'm thinking pinion bearing or transfer case output shaft slop? What about the u-joints?

-Joe

Click to expand...

I have not checked for slop in the rear driveshaft.
The front drive shaft u-joint has some play, but I'v never heard a u-joint sound like this.
I was sure it was the left side front wheel bearing (that's what the noise sounded like and , now I not sure of anything.
The tranfer case output shaft? How do I check this? Is it possible a bearing in the transfer case is bad?
Any suggestions would be helpful.