Hi,
Has anyone changed their powersteering fluid and differential fluid on a 2000 s500, mine has reached 150k.

 

Yes. You should change your fluids regularly. The power steering fluid can be changed in three ways. 1. Engine off, siphon out the reservoir with a suction device until empty and then fill with fresh fluid. Start engine, drive car around the block, etc, repeat the process a couple times. 2. Remove the low pressure hose at the pump and drain out fluid, fill with fresh fluid, repeat. 3. Take car to an oil change place and theyor dealer can use a hose in line flush and fill machine to remove all old fluid and put in fresh fluid. I have doneoption 1 a few times and the power steering fluid always looks new even after many miles. You can use regular, good qualitypower steering fluid (synthetic for your year, standard for my year of car) from a car parts store, no real need to buy the expensive MB brand power steering fluid, unless you want to,

Differential. Tough job to change unless car ison a lift as it is hard to get to anything under the car. Most oil change places can do this as they siphon out the old fluid and put in fresh GL5 differential fluid. Dealer can also, costs more. Some MB car's repair manuals inform to use a limited slip additive, I did not and everything is just fine with normal, GL5fluid made for all types of differentials. No real need to buy the expensive MB brand differential oil, unless you want to. Synthetic oil for your year, standard for my year of car.

 

Thanks for the info.

 

The diff was easy on ramps with a hydraulic floor jack as a safety catch.

There no crush washers, a threadseal compound is recommended when torqueing the drain and fill bolts. The thread seal is not the same as a permanent type thread lock (you don't want that).

Finally, make sure you loosen the fill bolt first, it's the upper recessed hex head bolt on the driver's side of the diff right above the drain bolt. You loosen the fillfirst because if you loosen the drain first and empty the diff and you are unable to loosen the fill you will never be able to re fill it.

You'll need a very large (IIRC 12 or 14mm) hex socket, an allen wrench does not allow enough torque to loosen the bolt, it needs to go on a ratchett. I got a3 set of large hex head sockets years ago for $6.00 at Big Lots to change the oil on my Peugeot.

You also need a hand pump to attach to the GL5 diff bottle to pump into the fill hole, mine took almost two full qts of 75W90 Mobil 1. Typically these pumps are marine pumps, I found mine at Wallys in the marine oil section.