illusive D1 noise undeneath, total mystery..

[bodhizattva]

Hi All,

Could use some help pinpointing some noise undeneath my D1, it really sounds like something is going to fall off and I can't figure out what it is!!!

The noise was there before I replaced the 4.0 with a 4.6. It was also there before I replaced all the bearings, cv joints, stubs in the rear, rear diff, front diff, driveshafts and ujoints so its none of the above. Had the plate off the transfer case and all the gears looked fine as we rotated them through while truck was off the ground and it did not make the noise running through the gears while all 4 tires are in the air. Its not the NRP cats or exhaust-they are totally secure.. Its not the sliders, or skids, bumpers or winch. Sounds like it between the four tires underneath, somewhere..

It does not speed up or slow down with acceleration/deceleration and once you're doing over 60 there is too much wind noise too hear. There is no vibration associated with it and turning, rolling in neutral or driving in 2,3,D,R does not change a thing.

its very noticible on any kind of little bump.

Its very noticible and hard to say where it is coming from.. Its underneath. with all windows down it surrounds vehicle

Sounds like a bell almost, something really loose. I have pushed, pulled and hung on everything underneath and find nothing loose..

I am clueless...

Any ideas what it could be?

 

[DeMak]

Did you change the exhaust and cats? If not, I'd guess that its a baffle inside one of those.

Doug

 

[bodhizattva]

Yup.. New NRP stainless steel cats and exhast. Got anotehr guess?

 

[Buddy]

Yup.. New NRP stainless steel cats and exhast. Got anotehr guess?

Rock in your hubcap?

Just kidding.

Are the shocks old or new? Have you checked the stone guards on the shocks if you have some with metal ones? Could be loose and rattleing. That's about the only thing I can think of.

 

[bodhizattva]

haha.. shocks and springs are ARB HD and are roughly two years old. I will take a look at the stone guards but really do believe the noise is underneath, not coming from a wheel.. It sounds like a bell..

 

[Buddy]

Is it there at when the truck is stopped or only while moving?

There is not that much under there that could make bell noises. "Bell" noise makes me thing big heavy metal. So that means heat sheilds and stuff are out because that would be more of a tin can noise. Maybe something loose or hanging that is clanking on the frame?

Have you tried to tie a little person to the bottom of the rover while you drive down the road? Maybe a small kid would work well.

Well I have no idea but good luck.

 

[landrovered]

I had similar sounds in the rear of my RRC. Check the rear ball joint, all the suspension bushings in the panhard rod, radius and trailing arms. Worn tie rods can clunk, worn bushings will bang, clank, pop and make all manner of loud metal to metal noises. Sway bar ball joints should be check as well.

 

[robertf]

are you surei ts drivetrain and not the body? looks like a different bumper in your avatar... could it be those brackets that go off of the fender to the running boards or bumpers?

 

[SactoDisco]

I have a similar sound on my 95. Kind of a rattle/clank/bell that seems to come from everwhere and nowhere at the same time. Scoot under and nothing is loose. I was thinking maybe the running boards or bumper caps or I dunno.

 

[bodhizattva]

Its definately not the running boards or bumper caps.. I am going to look at what landrovered suggested and report back.. thanks all for helping diagnoss..

 

[DenverCurmudgeon]

I had a similar noise. Every little bump caused a little squeek. I sprayed white lithium grease on my rear sway bar bushings and it decreased.

 

[crown14]

Remove the rear driveshaft and tighten the screw holding the brake drum on.

 

[barefoot]

Remove the rear driveshaft and tighten the screw holding the brake drum on.

wont help! its held firmly in place by the ds...i know for sure because i have no bolt there and no noises! :bigok:

how about the front and rear pinion dust flanges? do they rotate? if so remove them and use a punch to punch holes in 3 places and reapply.

also, if you let a pinion bearing go past the whinning stage....it WILL start to sound like a grinding/bell likish noise...

just some more to ponder!

enjoy!

 

[mngdih]

Have you had new brakes put on recently?
My disco II was making a tinging noise when i hit bumps. When I pushed the brake caliper forward or backward it was loose. Found out the guy who did my brakes overlooked the springs that float the pads.

 

[DeMak]

Hey Bodhizattvahttp://www.discoweb.org/forums/member.php?u=8870

Did you ever figure out the noise?

 

[az_max]

I vote for e-brake related. A drum has a nice ring to it when struck.

 

[bodhizattva]

Unfortunately no I have not figured out the noise yet. It still plagues me. I have not had the time to address it yet but I will crawl around under it soon, hopefully with a master tech friend, and run through this list. There are a few things posted I never considered and 138k means those things most likely need to be replaced soon. As soon as I know the problem, cure and fix I will post.

So here is a little more to chew on. I am thinking the transfer case should not be ruled out and I am really hoping its not the transfer case? There is obviously slack in a D1 driveline with 138k. We did have the plate off the transfer case before the 4.6 upgrade and all the gears rotated smoothly and looked ok.

The noise is the same as it was before total axle rebuilds including diff's, cv's, bearings, stubs, etc and rebuilt driveshafts on top of a 4.6 install.

Anyway.. After messing with the drop down gear adjustment over the last day or two I noticed that when the drop down adjustment is too taught, and the gear drop happens too soon when you accelerate and ease off the gas (around 30mph) you get the big bell noise/clunk that plagues me.. it does act up in conjunction with the driveline slack. Of course this driveline slack may be ringing that bell noise in all the other places listed above too and have nothing to do with slack in the driveline?? ( i hope thats not confusing)

It seems a little more taught when the diff is locked but it still rings on bumpy roads from what I remember.. I know it rings going downhill with transfer case and tranny in N. I will have to try the locked diff on bumps again tomorrow but I am sure it does not alleviate the noise..

brakes have been changed several times and the springs/pads make sense.. maybe the springs are just worn? everything posted above makes sense..

and its not the sway bar bushings either but thanks for the thought..

I really appreciate all the thoughts and insight. Thank You.

 

[BJ64]

I agree with Crown14 and az_max. I think there is something whacking the emergency brake or bouncing around in there. I wonder when you go back under the car if you whack the E brake with small wrench if you would recognise the sound?

 

[Max]

Look at your rear links. grab hold and shake. I have a bad bushing/bolt that is making a nice clang. I have the parts on order (thanks Steve) and hope 90% of my noise will be gone when new bushing in. Max

 

[Rocky]

I'm puzzled by the descripton. Suspension movement causes it and it doesn't vary with speed.
Am I reading that right?
Wierd. But then my 95 with 146k has its collection of special noises as well. But it goes and therefore I'm happy with it.