E320 wgn... strange noise in back - PeachParts Mercedes-Benz Forum

tbenner · #1 07-14-2007, 10:01 PM

This is a 1995 E320 wgn. It sounds like something is hanging and banging on something in the back.. almost as if it is sliding and banging into something hard. I was convinced that the jack was loose. It's that kind of sound.

It didn't do this yesterday. Today all I did was install a new belt and fan blade and front brake pads. I climbed under the back to hit the bleeders and brakehose connections with PB Blaster as I plan to replace the hoses and brake fluid tomorrow. When I took it out to bed in the front pads I turned right out of the driveway and it thunked. Turned left onto the next street and it did it again. I came home and took the jack out of the car and test drove it and it is still doing it. Nothing feels wrong with the suspension.

I got back under it tonight and shook everything I could get my hands on and nothing feels loose.

Anyone ever experienced this?

Thanks,

Tim

Ed Richardson · #2 07-15-2007, 11:27 AM

I had a similar problem, turned out to be the cargo cover on the back of the rear seat was not properly stowed. I pulled it out to the end and let it roll up straight, no more banging.
Ed

tbenner · #3 07-16-2007, 10:08 PM

Thanks Ed. I removed the cargo cover and drove it again and I still get the clunking noise.

I am afraid there is something going in with the rear suspension. The noise comes from the right and it looks like it is riding higher on the right by about a half inch.

It is baffling. Nothing is loose under there.. at least not apparent from a good tug. But when driving it sounds like the jack is loose.

Seeking help from a suspension expert.

Tim Benner
95 E320 wagon 141K
67 Spitfire (for sale on CL)

saumil · #4 07-17-2007, 12:14 AM

Could be your exhaust. Push the car (perpendicular to the wheel) at the driver side rear wheel, leg push is enough and you would hear the banging behind the wheel.

Ed Richardson · #5 07-17-2007, 12:21 AM

This is a hip shot, is it possible that one of the leveling accumulators is going bad?
Ed

tbenner · #6 07-17-2007, 07:00 AM

I'll check the exhaust tonight. Then up on the ramps.

How does one check the accumulators?

It is definitely lower on the left than on the right... on the right I can get 4 fingers plus between the wheel arch and the tire on the left 4 fingers is very tight. Not precise measurements but it was dark out there.

Thanks for your help!

Tim Benner
95 E320 Wagon
67 Triumph Spitfire

Ed Richardson · #7 07-17-2007, 12:33 PM

My knowledge of the suspension on these cars is just about zero. Not sitting level made me think of the accumulators, and the possibility of one of them being bad. The only way I would know to check would bounce on the rear and see the reaction, There might also be a broken strut or bushing. You need more help than I can give.
Ed

AnnArborBenz · #8 07-17-2007, 01:08 PM

Have you checked the rear washer fluid resevoir, power antenna, and stereo amp.....? All are located in the rear left wheel well.....

tbenner · #9 07-17-2007, 01:25 PM

The washer reservoir, amp and antenna unit are all tight.

Here is the wild thing. I drove the car in the rain today. The noise has stopped and the car is level

. I'll be scratching my head for a while trying to figure that out. Odds are that it won't stay that way.

Thanks for your help!

AnnArborBenz · #10 07-17-2007, 02:08 PM

Well, the only other thing that I have ever replaced back there was the two stabalizers under the third seat.....have you checked the tightness on the two large black rubber seats on the stabalizers....

Good Luck and If you are interested, I have the following that was custom made...

In my 1995 E320 Wagon I had a custom box made with a 10" subwoofer, spot for CD unit and large pioneer amp.... I only have the sub woofer left in the box as I do not want to crack it open....anyway it takes the place of the resevoir cover....

J. M. van Swaay · #11 07-17-2007, 03:29 PM

If the suspension accumulator(s) is(are) bad, you will feel and hear a clunk when going over bumps.

Here's another long shot. (very long but easy to check) Under the right rear of the car is a black plastic panel that covers the fuel filter and pump. The panel comes off easily by removing four plastic nuts. The pump and filter are held in place with a small bracket. If this bracket were to come loose the pump and or filter would be free to bang around a bit. Don't know if this could cause your problem but if it were my car, I'd take ten minutes and check.....

J. M. van Swaay

Bob Weir · #12 07-18-2007, 12:14 AM

Self leveling tests:
Measure rear suspension height [star center to fender lip] on both sides. With the engine OFF, put about 300 lbs [children like to do this] in the cargo area. The rear will go down from the added weight. Turn the engine on and the rear suspension shoud return to its original height.

While engine is running, remove filler cap from reservoir. If returning fluid is foamy, one or both accumulators are ng. High pressure [feed] hose from bottom of reservoir goes to bottom of PS pump. Hose will deteriorate with age and leak. You must use Febi 2615 Hydraulic fluid in reservoir.

Self leveling controller arm is attached to sway bar. Insure connector on sway bar is tight.

Rear suspension has many links. Sometimes they'll clunk when bushing is ng.

Bob
1/2" variance from left to right side is acceptable.

AnnArborBenz · #13 07-18-2007, 12:56 PM

Hey Bob, I have an easier test that the kids also love.....

We drove our 95, Wagon around town and hit some bumps here and there,,,,guess what....kids hit the roof, the stabalizers are bad.

Even when you put the brakes on coming up to a light, if the back end pushes and bounces a bit.....time to replace.

I tricked my dealer when I had mine done.....I got a quote and then ordered the parts from this site, and oil.....I then took the car to the dealer and said...here ya go, just as promised, OEM parts...they looked at me and said NO WAY..Cannot install customer parts, you must order them from us....

I said, oh...sorry, thought you wanted the parts (he did not stock) and then the manager came out and said that they would do it this one time...

Saved me about $300 bucks.....

tbenner · #14 07-18-2007, 01:28 PM

Bizarre are it may sound, the clunk is still gone today. I was planning to replace the fuel filter (in the process of making the car my own) so I'll do that check anyway.

I am looking forward to testing the SLS if somewhat apprehensive about the results.

Regards,

Bob Weir · #15 07-18-2007, 03:53 PM

AnnArbor

A few months after I bought my 94 e320 Wgn, my daughter did a similar test. With driver & 6 passengers, she was cruzing the streets of Ocean City NJ and not paying attention to the man hole covers that often are a few inches above street level. Hit the intersection bump, caught the man hole cover and ripped the resonator right off.

Fortunately, I was able to disconnect trailing exhaust pipe & muffler. Kids definitely loved the "hooked up" sounding Benz until I had resonator replaced. In hind sight, I wonder how it would sound without the resonator?

Bob