ptirado961

Have 128k on my 2005 E55. It is running well, but things have been TOO QUIET for too long... I am on the edge of my seat now wondering when the next thing might break, and was hoping some of the experts on this forum might chime in and give me a heads up on things I should maintain preemptively that I may expect to fail soon.

Thank you for all of your responses. I am sure it will save me some expensive surprises...

Pmarino

I'm no W211 E55 Expert but here's my $.02 I'll assume your doing ALL your fluid maintenance (that includes SC oil every 30k at least). I will speak from experience..... Fuel filter (say it three times). You should either build a BBirdwell current monitor or IMO, just change it (every 20k-30k ,like any other car) Also check fuel pump relay and socket. . Replace crank position and cam position sensor. (all 3 of my MB's have over 100k and all have a new CPS) Inspect/ replace all the vac lines same for cooling circuit.
Hpoefully that keeps you from a no-go on the side of the road.

FunkTron

Get in there and pull / regrease wheel bearings. Not too terrible of a process (just messy) and helps keep things rolling along (literally). With all the weight, speed, and age these things are exposed to the grease is just cooking.

It's on my soon to be done list.

bbirdwell

Flex discs and the driveshaft center support bracket and bearing. (Bracket has a rubber insert that distorts with age. Don't try to re-use it.). If you crawl under the car and inspect the flex discs, look for cracks in the discs. (Pelican Parts has a nice writeup on this, BTW.)

Serpentine belts, all pulleys and tensioners on the engine. Buy a new supercharger idler pulley for $540 or rebuild it for $27; the DIYs are out there.

If you've never done ball joints, bushings, and tie-rod ends, now is the time to look into it.

If you're not replacing the fuel filter, pumps,and relay regularly, you're asking to be stuck on the side of the road (or blocking a bridge over a river). No more than 60,000 miles between changes and I recommend you pre-emptively replace the fuel pump relay with a larger capacity relay and socket (Unless you have a 2006 which has dual relays, not a single relay.)

Buy a Solar BA-5 battery tester and check your batteries; if at half-strength or less, replace now before they fail.

Consider pre-emptively replacing the alternator's voltage regulator; the brushes are a wear item. You may still have an alternator failure due to a bad bearing later but this is cheap and easy to perform. Be sure to disconnect the battery first! Do NOT have your key fob in the ignition when disconnecting or connecting the battery cables or jumper cables!!!

Be advised after reconnecting the battery every module in your car will have a stored code for power and communications failure. Everything will work but the first time you run a quick diagnostic you're going to see a massive amount of stored codes. So long as they are stored and not current, you can just erase them.

mekantor

I'm ~60k miles further down the road, here are some things I had to replace because they failed:
Ignition coils, spark plugs, spark plug cables
Shifter connector bushing (you'll hear metal clanking when shifting)
All pulleys and tensioners
Oil filter housing gaskets (there are 3)
Alarm module (drains main battery once it's internal one dies)
Heater valve
Crankshaft position sensor
Airmatic struts
Airmatic pump
SBC Pressure Accumulator
Secondary Air Pump

CharlyE500

How much cost you to do all that ? I did Coilover conversion just to avoid airmatic failure.
I think not much prevention you can do... just do fluid change, CPS, coil, spark plugs/cable. The rest just wait until happen. IMO.

jumph4x

122K on the clock and I figured the block is done getting broken ii right about now for me the fun is just beginning with the drifting and everything.

MACEDON

How the hell do you replace that filter... seems like the biggest pain in the ***

bbirdwell

Not difficult at all. Just takes a really big wrench or pliers to remove the big honking screwed-on rings that hold the filter and pumps in the tank. Don't forget to buy new O-ring seals that go around the filter and pumps under the screwed-on rings.

When you disconnect the old fuel pumps, tie a 6'-8' length of paracord around the ends of the lines; when you pull the fuel filter out the paracord will come with it. You want enough line so the other end of the paracord is still hanging out of the hole where the fuel pumps install on the other side of the tank. Now untie the paracord from the old filter's lines, tie the paracord to the new filter's lines, and you can now pull the new lines over the saddle in the tank and to the new fuel pumps. Much easier than having your arm in the tank trying to push flexible lines over the saddle.

Remember, the newest fuel filter requires the newest fuel pumps due to new fuel line connectors. Both filter and pumps will require adapter cables to connect to the original harness.

Pmarino

There is a cheap tool that works A large blunted standard screw driver placed against the plastic wing and struck with a hammer, works. A small block of wood could also be used. CAUTION: I would not attempt to open tanks, that are more than 3/4 full.
FWIW...My fuel gauge read roughly 3/4 full and the fuel was right up to the lip of the hole

mekantor

The struts were the most, it cost whatever Arnott charges, but hey lifetime warranty! They already swapped front struts 3 times for me.

I do my own work, so everything was pretty cheap, most of these parts are in the $50-70 range, some I bought used like my alarm module from a CLS.