560 SEC - Hard ride / vibrations at speed

[nickbe]

Hi everyone,

After several years and much restoration work, my red 560 SEC is in fine shape with all the usual rust areas sorted to a high standard.

There remains one area I would like to improve, namely a somewhat harsh ride which gets worse at high speed. It is not the usual 'wheel wobble' you would associate with imbalanced tyres, it is more like the car is picking up all the impefections on the road and transmitting them into the cabin. It is not too terrible - however as the rest of the car is in such good shape it bothers me!

It is an old car and I would not expect it to drive / handle like my company BMW 3 series (not that I would want it to), however I do feel that cruising should be a little smoother!

I have replaced the rear spheres (the first thing reccommended) however this has dome little to improve the ride.

All suggestions gratefully received.

Cheers,

Nick

 

[television]

How about the engine mounts, if they have failed they can transmit lots of road and engine noise along with some harshness into the cab, if you can feel the engine through the steering wheels and pedal then they have gone, you can look in the engine compartment to see if the fan is sitting centrally in the fan shroud

 

[nickbe]

Thanks for the suggestion - I don't think the issue lies with the engine. The fan sits dead centre in the housing, also if I run the car in low gear and high rpms there is no problem.

Basically the suspension is too harsh and is not soaking up the bumps as it should. The faster I go, the harsher it gets.

I have replaced the SLS spheres and the front shocks seem OK. Could this be down to the various rubber subframe bushings and if so, what should I try first? It is a 23 year old car after all.

Cheers,

Nick

 

[television]

It needs an expert on this Nick, sadly that I am not, maybe member Richard Moakes can help

 

[BAZZER1]

Hi Nick
What Tyres are fitted ?? as sometimes, as I have found to be the case on my E320cdi, the wrong type of tyre can give an uncomfortable harsh ride. I carried out all the same checks on mine, Spheres, Shock Absorbers and Springs and also reduced the tyre pressures slightly as advised by a Forum Member, the later did help a bit but I will soon be changing my tyres for better quality ones that will hopefully give a softer more comfortable ride.
Best regards
BAZZER1

 

[mikestrivens]

I had a not dissimilar problem with my W140 and turned out to be the valve that controls the self levelling. It had failed causing intermittent vibration and gradually the rear sank a little. Once this valve was replaced, along with the spheres, the suspension was transformed. On the W140 has the same part as the W124 and SPR Autos managed to get a secondhand one for a few pounds. I don't know if yours is the same system but it is worth checking the valve, if your car has one, is working.

 

[television]

We do have ADS1 and ADS 2 not much info around on the 1, quite a bit in WIS on the 2

 

[mikestrivens]

We do have ADS1 and ADS 2 not much info around on the 1, quite a bit in WIS on the 2

Which version of ads would be on the W126?