Black SLS Fluid. 82 300td Hints and tips?
 

I did some searches, but wanted some feedback on keeping my system mint.

my ride rises up when I start it. couple inches or so.

But I just flushed my fluid and added a new filter. it is BLACK, like diesel oil black.

But the fluid is still "light" and does not smell like diesel motor oil.

This leads me to think the accumulators are toast.

What do the pros think? should I rebuild the pump?

Thanks for your time guys.

Is it clear after the flush or still black? Keep flushing till it gets clear? Did you put the return line in a bottle and keep refilling the reservoir until it ran clear? If you don't have ride problems, the accumulators are probably ok.

I pumped out almost 2 liters of black fluid I think. I tried to clean the reservoir when it got low. But yes the fluid is still "black" due to remaining contaminents. Plus it was dark (gets dark at like 530 now :mad:)

The only reason I didn't purge till it was clear was because this bloody stuff costs 25 a ltr.

Ill drive it around tomorrow and check the quality of it and report back.

The ride is good, though it may be "hard" its difficult for me to tell.. way better than my 1/4 ton toyota anyway ;)

If the rear is lifting when you start the car up after it's been sitting for a while you've got a leak in the system. This causes the rear to settle down over time. The most common leak is the SLS valve.

The fluid can be black from being old, or from motor oil getting in through the pump. I'd think about doing a good flush with mineral oil and run the care for a bit and see if the level changes or if the fluid goes black again. If it stay's clear then you're good, if the level changes or it goes black again you've likely got a leak in the pump.

The Febi fluid is available for $10 per liter. MB just rebrands Febi fluid. There are also other much cheaper alternatives. The SLS valve leak is an internal leak and not something that necessarily needs to be repaired as long as the rest of the system is working. Sometimes mine leaks down overnight and sometimes it doesn't. It did it far more frequently when my accumulators were bad. If the dirty fluid is a result of contamination with engine oil, that seal between the pump and the engine should be replaced. But I would not assume that's the source of the problem. I'd purge the system with less expensive fluid, clean the reservoir and then see if it get dirty again quickly. If so, I'd think the problem was contamination with engine oil.