Front end Rattle - Please help diagnose

[rageagainstmrclean]

'97 Passat TDI 150k

So far I've replaced the;

Struts
Strut mounts + bearings
control arm bushings
tie rods
wheel bearings
ball joints
passenger side axle

And still, when I'm driving slow over my gravel driveway there is a loud annoying rattle coming mostly from the passenger side front. Granted, all of the above needed replacement so I thought when everything was fixed the rattle would be gone. It's louder than ever. The sway bar bushings are tight. I bought new one but they just didn't need to be replaced.

Any help would be greatly appreciated.

 

[Yblocker]

Does the rattle go away upon application of the brakes? Old pads with broken tension springs can rattle. When you even lightly press the brake, the pads get pressure and can't rattle. Mine did this before I did my suspension and brakes. It's tight as can be now. Fan shrouding/mounts can rattle too.

 

[rdkern]

Penny in the heater grate?

 

[RUGsux72]

gravel in your hubcaps? Sorry, couldn't resist

 

[Lug_Nut]

Strut mounts + bearings

Oh. So you've already found the problem.....

Lucky you. You can fix this in about 10 minutes. The top strut bearing nut is loose.
Open the hood. Remove the retainer nut and the top strut plate.
Additionally tighten the bearing nut that wasn't tightened enough the first time.
Reinstall the top strut plate and the retainer nut.

 

[rageagainstmrclean]

Yblocker: I feel kind of dumb. I'll check the brakes and get back to you. That seems like the most likely culprit.

Lug_Nut: I'd be surprised if it was loose. When I replaced the struts, I hit the nut pretty hard with the impact wrench.

Maybe this helps but when I push down on the car to make it bounce, there is no rattle - this seems to point to the brakes

 

[Lug_Nut]

Maybe this helps but when I push down on the car to make it bounce, there is no rattle - this seems to point to the brakes

And on big bumps there is no rattle either. What creates the noise is rapid, but small bumps. Pressing the car up and down is too slow. Big bumps and dips are too slow.
I'll still stick with my guess.

 

[rageagainstmrclean]

I just checked it this morning. I took off the top strut plate and tried to tighten up the nut. The nut is very tight. It just turns the shaft of the strut.

 

[Yblocker]

To tighten that nut you do need to counter hold the shaft with a 7mm allen.

 

[Lug_Nut]

Some strut shafts have external flats, others use an internal hex. Whatever tool is needed, use it ......

 

[Abacus]

My bet is the swaybar end link bushings. Over time the little round donuts get compressed and the control arm hits the metal of the swaybar end link. I put some new ones in and it cured the same issue I had with mine. I know you said you checked the main swaybar bushings, but with any load on the car, the end links will seem tight, but rattle when they move. Adding a washer or two can also tighten them up, just don't overtorque them or they can snap in half...mine did.

 

[rageagainstmrclean]

I held the shaft and tried to tighten up the nut. It did not budge. The allen wrench would have rounded out or bent before the nut would have turned.
But taking a look at the strut mount something doesn't look right to me:

The strut is off center and the mount looks like it's tearing up through the hole in the sheet metal. It sure wasn't off-center when it went in. I'm not used to the VW style of strut mounting so I could be completely wrong. The mounts are brand new. Got them here: http://www.ecstuning.com/Volkswagen-Passat_B4--TDI/Suspension/Shocks/ES5121/
Any thoughts?

 

[Lug_Nut]

Please tell me that isn't a grease heater hose!

 

[Lug_Nut]

The ECS part image doesn't look right, not like all the mounts I've used on A3 and B4. I'm more used to seeing mounts that look like these:
http://www.idparts.com/catalog/product_info.php?cPath=36_66&products_id=445

 

[Yblocker]

It looks like your strut assembly was put together with the big upper mount pushed in from the top (?), with no top cap.

It should look like this:

Forget the brakes for now, Lug Nut had it right. That upper mount has to be addressed.

 

[rageagainstmrclean]

Lugnut: I think they sent me the wrong ones. I talked to ECS when they first arrived in the mail because they looked so different from the ones in the car. The existing ones were a lot larger in diameter but I was assured they would expand over time. I think they were just bull****ting me. Not exactly sure why though.

Yblocker: I took off the top plate to take the picture. The mounts were installed from the underside. They look like they are extruding up through the sheet metal. Any time now I think they'll pop through. ha ha

 

[Yblocker]

Right- OK well at least you know what the trouble is now! Order the proper mounts from Bora Parts or IDparts and use the other ones for doorstops or something..."expand over time"...sounds like something Carl Sagan would say.

 

[rageagainstmrclean]

I swapped out the mounts with the old ones that I hadn't thrown out yet. To be honest, the old ones don't look bad except that the hole is eccentric and no longer in the center of the mount.

It doesn't exactly mean much because I'm using the old ones but the rattle is just the same. The steering feels tighter and more controlled but the rattle is driving me nuts.

I'm going to re-check the sway bar ends pry around with a bar to see if anything moves but it doesn't look like I'm any closer to figuring this out.

 

[Yblocker]

Don't forget the possibility of brake pads rattling. The test is whether or not the noise goes way upon light application of the brakes...

 

[rageagainstmrclean]

Oh yeah I tried that. Still rattles

 

[RIP TDI]

Check the sway bar end links. The mounting stud can separate from the bushing body, causing a rattle.

 

[rageagainstmrclean]

Ok. Two things.
I jacked up the car, pulled off the wheel, and put a 2nd jack under the rotor to push the upper mount up into the body of the car.
1. As I grab the strut by the spring and push and pull I can feel the strut squeak and move against the upper perch. Is this normal? Is there supposed to be a rubber cushion in between the spring and the perch? It seems like there should be.
2. On a whim I removed the lower control arm to check the clearance b/w the bolt and the inner metal of the bushing. It looks like it has quite a bit of room to wobble. I was told I don't need the control arm sleeve because I was using the TT bushings. W.T.F. It looks like that is wrong. So I guess I'll be picking these up:

 

[rageagainstmrclean]

Just in case anyone cares, the sleeves were the problem. I guess I didn't really need the internet to figure that one out. Who would have known that you need a sleeve within a sleeve?

Oh, and they're $0.63 at NAPA

 

[Abacus]

Where did you get the bushings from? I didn't need any sleeves when I installed mine, nor my brother's on his '96 B4.

 

[ecarnell]

I just installed tt bushings and I didn't order/install any sleeves. Never seen this before are the id's of the stock and tt's not the same? I'm assuming the passat and jetta use the same bolt size.

You didn't happen to install a front lca bolt in the rear position by chance? As I think they are slightly smaller dia?

 

[teeth]

Random thought...I've had a rattle from a bad water pump when the bearing started wearing out.

 

[rageagainstmrclean]

I got them from MJM Autohaus:

These are the ones I bought.

https://www.mjmautohaus.com/catalog/product_info.php?info=Meyle_8N0407181BMY.4_Control_Arm_Bushings_4-PC_TT_R32&products_id=869

I'm pretty sure I used the same bolts when I re-installed the control arm.

 

[rageagainstmrclean]

It's been a few weeks since I installed the spacer. I guess "installed" is a good word for it but they didn't go in easy. I'm still not thrilled about it because I can still sense some vibration coming through the steering wheel. (I have new tires, balanced and just had an alignment) There is also some definite bearing noise coming from the passenger front. This is with a new wheel bearing!!! I guess it doesn't pay to get the 30 dollar bearings from NAPA.

Since others here have put in the TT bushings on their B4, I guess it's pretty much confirmed that the bolt size is the same as the A3 Jetta? I wonder what the heck bushings are in my car? I'm not going to even bother trying to get the right ones from MJM. After what I had to go through to get the correct shock mounts from ECS tuning, I just don't think it's worth it.

 

[rageagainstmrclean]

So I just bought new bolts, tt bushings, front polyurethane bushings.

I checked them with a caliper.

Bolts: 12 mm

Inner sleeve of front bushing: 13mm (very minimal slop - feels about right)

Inner sleeve of rear bushing: 14.5 mm (a good amount of slop - doesn't feel right)

Does anyone have experience with this? When I checked my old tt bushings after I was having clunks coming from the front, the inner aluminum was wallowed out and elongated slightly. W.T.F.?