Front End Chunking at all speeds???

[Chris97Exploder]

I have a 97 Explorer Sport with control track. At all speeds it makes a chunking metal on metal noise that shudders the vehicle. Its not the front diff because I took the driveshaft off and it went away. I recently put in a different T Case because it did this before and it went away for 300 miles. I can't believe that this T case would be bad and suspect the other wasn't either. Could it be the CV on the driveshaft? It slides in and out easily parallel to the road, but doesn't "seem" to have any rotational play. Does anybody have any ideas???

I'm wondering, and it would take somebody on here who knows alot about these systems, if maybe something like the shift motor etc could be screwing up not engaging the system correctly. Because it will do it and it gets progressively worse and goes away. But its harsh enough that you don't want to continue moving.

THanks,
Chris

 

[Rhett]

You took the front driveshaft off, and the sound went away? I'd say that narrows it down quite a bit. Those u-joints (aka CV's) can seem fine when you've pulled them and move them around, but under driveline stresses they get noisy.

I'm not too familiar with 2nd Gens or their Control Trac, is this a fancy word for all-wheel drive that some of the 2nd gens had? I did not think any Sports had AWD.

 

[410Fortune]

while going straight? or while turning?
I say take the front shaft out again and see if it goes away witht he new t case.

I suspect your CV joints, but its odd that you say it wnet away for 300 mi with the new t case. Could just be coincidence

 

[Chris97Exploder]

It does it while going straight or any direction for that matter. I already took the d shaft off the 2nd t case because it was the only way to get it home. It is very harsh what it does, harsh enough that you don't even want to limp it 5mph or less. U joint is fine on diff end of shaft, but from other trucks that I've seen the cv on the d shaft go bad they start to click and grab and then just blow up. This speeds up as the vehicle does and it starts as a quiet metal on metal chirp and then gets very very bad and has to do with some major metal on metal interference somewhere? I dunno I'm just getting very sick of this explorer, I got it because my mom had one and she never had problems and this SOB is nothing but problems.

But hers wasn't the control trac. For who asked the control trac has 3 options AUTO, 4HI, 4LO. It senses slippage and automatically engages the front diff whereas my mothers style was 2HI, 4AUTO, 4LO I believe, and you could keep it in 2wd if you wanted.

I have read to check the CV to leave it attached on the T case and reef on it to try and get it to pop. I have a spart shift motor and was starting to think maybe its not engaging right or there is something that is electrically wrong? But I do not have ANY lights flashing on my console, so that from what I've read rules that out.

 

[410Fortune]

on a 97 you can do the brown wire mod and get 2wd I believe.

Did you put fluid in the T case? I know it sounds stupid, but I have to ask.

Now to pinpoint the noise start like this:

Put truck on jackstands, I assume you can know how to safely out all 4 tires up in the air, with 4 jackstands, so I wont go into that.

But lets start with the front.
Raise the front two wheels off the ground.
do a shakedown test, this means start grabbing and turning. Listen, feel, look for looseness, worn bushings, loose parts, etc....the whole front end while the tires can spin.
Steering, shocks, sway bar, ball joints, driveshaft, etc. Everything.

If this does not help the next step would be to duplicate the noise with all 4 tires int he air. Meaning start truck and put it in drive.

NOW this is NOT a safe thing to do if you dont do it right!
If you dont feel comfortable getting under a AWD truck running in gear on 4 jack stands, take it to a shop. I will reccommend you remove the front rear driveshaft since this is a AWD and do this with only the front driveshaft hooked up.
The front tires in the air, the rear tires blocked properly, E brake on, etc.

Slowly put truck in gear, See if you can find the noise at idle.
I have NEVER had to hit the gas to find a noise as you describe doing this. Usually it takes all of 5 seconds of the negine running for my to be under there, listening and confirm it is definately coming from _________.

In my case recently it was the rear diff.
I have also used this to find bad cat's and U joints.

Do this as a last resort, I am not even 100% comfortable under a truck I know is supported by the appropriate jack stands when all 4 tires are up in the air.

 

[Chris97Exploder]

Yah I filled it with fluid. We started it when it was on the lift at my buddies garage when we were diagnosing the first time and when all tires are off the ground nothing happens because there is no pressure being put on the components. I'm gonna have to get a buddy over to help me go through this thing but it may have to wait till after the weekend.

Thanks

 

[410Fortune]

good luck, keep us posted!