Nothing more than supply and demand, I think. I don't remember their capacity (4-5 quarts?) but they're about the size of many washer fluid resevoirs, made of heavy plastic, basic cap with a metal return line attached and a small filter which resides in the neck of the tank.

Their failure is pretty rare; I'm probably the only one on the forum who has had to replace one. I don't know what caused the holes to develop but I suspect high desert heat and time.

Used resevoirs can be found for $60 bucks or less. Salvage yards units would cost much less, but are rare in the yards as only w123 wagons and long wheel base w116's come equipped with SLS and use the same resevoir. I've only seen one in three years...on a euro w116 (450 sel?) with the coolest creme green velour interior; but didn't have the proper tools to get it off... :mad:

I just replaced the accumulators in my 1990 560 SEL last night. The ride improved dramatically, though I now have some leaks at the fittings. Hopefully all that is required is a tightening.

So if I unscrew the cap and lift it out a bit, I should be able to see fluid circulating back into the reservoir while the engine is running?

Yes. If you're going to do that much work, change the fluid while you're at it. Let the return line run into a container of some kind and feed fresh fluid into the reservoir.

pulled the cap off yesterday, i didn't see any flow...guess that's why my rear was sagging...i was pulling a trailer. the fluid level is full. today the rear seemed level, but i dropped the trailer last night. I wounder if the pump is shot?

Try starting the car and then have to adults sit in the back with the rear open and your feet on the ground. You can feel the rear lift, that is if the pump it working. If nothing happens then your fluid is low or the pump isn't doing it's job.

Hi, I'm new here, but i've been reading this forum since I have my W123 300TD. I am also sorry, if a similar problem has been discussed before.

The thing is - I have changed both the accumulators and the SLS valve (a tested used one) - my car does rise up as it should and the ride is not hard, nor bouncy - the only problem is that it sags overnight.

The symptom, which I find uncommon, is that after the engine is turned off - I can hear a noise of something loosing pressure - like a tire deflating - could this mean that everything is working fine, only there is a loose connection in the system?

I just wanted to make sure, before rebuilding the pump/changing springs/struts. Maybe you could advice on the next step.

Many thanks.

The hydraulic shocks come to mind. Do you notice any moisture/leaks around the spring perches?

Valve rebuild. Cheap and relatively easy.

If only it were so cheap and easy with the T124.

Biodiesel300TD {Andrew} sells rebuild kits for the W123 300TD, with instructions. And pictures!! I've purchased 4 from him I believe.
A great person to do business with!!! Have no fear!

Thanks, guys.

I'm guessing, that it could be the struts, but since those are so expensive, I'll do a valve rebuild.

If it was the struts youd be leaking. Its the valve.

300td wagon with hibernating SLS...
 

Hi:

Rear suspension has been low on my list of priorities. The car's rear has been riding low all along, but drives ok by my standards. I looked in the SLS fluid reservoir the other day and learned it was empty.

When I do fill it, I'm prepared to find some sort of leak. What are the chances that the pump and valve and accumulators are still functional, given that the system has presumably been critically low on fluid for several years?

Thanks in advance for your thoughts!

Cheers,

Brad

The chances of the pump still working are minimal.