purplegrog

I'm planning on overhauling the suspension on my 4matic wagon sometime in the next few months, as I've hit 210k+ miles on the car, and some of the suspension components are worn. While pricing parts, I've found that the lower control arms seem to be inordinately expensive ($5-600 per side). My questions are twofold - with this many miles, should I expect that the Lower control arm will need to be replaced (the lower ball joint for sure needs to be)? Is it more practical to expect to just press out and in the control arm bushings instead?

If the control arm bushings are not cracked or worn out I'm not above reusing them, but I'm expecting to replace the CV Axles, shock, upper control arm, tie rod ends, and sway bar end links. I've done this job on my previous car, but it was a rear wheel drive car (so no cv axles in the mix) and it seems by comparison the RWD is going to have been a lot easier than this one.

Please forgive any typos. I'm not wearing my glasses or contacts and I've already caught some embarrassing typing mistakes.

AUTOdidact

In case you´re talking about the FRONT suspension, we have the same problem. One front roller bearing (fluid-filled) leaks, so I must replace this - already purchased OE bearings (Mercedes offers an overhaul-set including the bolts), ball joints and a cheap press on eBay.
Never thought about purchasing the whole control arm.
I´m still hesitating because the air strut must be vented to do this job - what if the car doesn´t come back up again?
In case everything turns out well, I´ll make a YouTube video out of this...

purplegrog

Good call out. Yes, I'll be working on the FRONT suspension. Fortunately I have coils in front so at least I don't have the additional wrinkle of having to work on air suspension.

AUTOdidact

The OE part numbers (one side front lower suspension arm, part numbers are identical left and right) for your and my car are:
A2203309807 (3 roller bearings: 1 front, 2 rear - these are pressed in from both sides into the rear part of front suspension arm, so no idea yet how to get these out...)
A2209900099 (set of bolts, nuts and washers - must be replaced too)
A2113300335 (ball joint)
N000000003281 (upper nut for ball joint)
A2029900851 (lower nut for ball joint)
The rubber bearing in the middle of the suspension arm (where the strut is connected - this isn´t shown in the official parts-diagrams) I purchased from Febest, part number there BZAB-038.

PS: These fluid-filled bearings may fail all at once due to fatigue even if they look still fine from outside. For this reason I will change all of them at a time.