So the other day the kid comes in all flustered and says "dad we need to rotate my tires really soon, the fronts are really wearing"....these are good Michelins with about 20K on them. With a busy spring I'll admit I hadn't looked at the 240 closely for a couple of months, but sure enough, the inside band of both front tires is nearly bald....sonny has been driving the car almost 40 miles a day to school and back.

Took it in to town to a trusted indy alignment guy who does all the front end stuff for the other trusted indy who services all the blue-haired Benzes in the nearby wealthy retirement community. Turns out a bad ball joint on the upper passenger side, which means a new control arm. The rest of the suspension is fine according to him. I asked if it made sense to change out the DS also, but he said he's of the opinion that if the original parts are sound, it's better to not replace them.

The bill will be 310 dollars, including mounting and balancing 4 tires and rotating the worn ones to the back and the subsequent alignment. The only thing I notice is he's nicking me 104 dollars for the control arm kit, which appears to be almost 2x what I could buy one for here.

opinions? I've left it there till tomorrow so I'm not going to back out now and do it myself and we really can't afford the down time waiting for a less expensive part.

__________________
You're a daisy if you do.
__________________________________
84 Euro 240D 4spd. 220.5k sold
04 Honda Element AWD
1985 F150 XLT 4x4, 351W with 270k miles, hay hauler
1997 Suzuki Sidekick 4x4
1993 Toyota 4wd Pickup 226K and counting

Not sure I understand the mount/balance part if they're just rotating front/rear...

$200 or so labor doesn't sound bad for front end work plus an alignment.

__________________
My occupational hazard bein'
my occupation's just not around...
1980 300SD
1980 300SD

Costs more to have a part ready to install the same day.

Sixto
87 300D

If the inboard corner of both fronts is equally bad, I'd suspect something more than just one UCA. I'd look hard at the LCA bearings and the camber adjustment.

$310 for rotating, re-balancing all four, the UCA parts and labor, and a four-wheel alignment doesn't seem too bad.

But the diagnosis doesn't seem to completely match the symptoms. I'd ask specifically for before/after camber and toe numbers and ask specifically about the LCA bearings.

Update. It's finished. It turned out to be the PS upper control arm and a DS tie rod end. Both replaced and the rest of the front end checks out fine.

__________________
You're a daisy if you do.
__________________________________
84 Euro 240D 4spd. 220.5k sold
04 Honda Element AWD
1985 F150 XLT 4x4, 351W with 270k miles, hay hauler
1997 Suzuki Sidekick 4x4
1993 Toyota 4wd Pickup 226K and counting

FYI, I just paid ~$600 to have my indy do both UCAs and an alignment, to fix the identical issue, so ~$300 sounds about "right". I'd have done the work myself but couldn't figure out the problem, so I'd have been relegated to replacing parts at random until I accidently replaced the bad one. They couldn't detect the problem either.. until they pulled the UCAs to replace the sway bar bushings that were shot. Then the loose UCA ball on the drivers side was obvious. Just that one, and some massive toe out, were what caused all the wear on both front tires.

We still don't know where all the toe out came from, but the UCA was causing visible negative camber on both fronts. Once the UCAs were replaced, the camber was exactly in spec according to the before numbers from the alignment shop.

__________________
'83 300DTurbo http://badges.fuelly.com/images/smallsig-us/318559.png

Broadband: more lies faster.

Changes in either Toe or Camber affect each other.

(If you've ever replaced the front bearings and then "Set" the retaining Nut,
You'll understand.It takes 2-3 trys to get it "Set" right.)

Set the Toe and then turn around and the camber is off.
And Vice Versa.

"Thats a Why" we usually find a REALLY Good Tech,
(Helps if She or He Is Also OLD)
at a Mercedes Dealership to do the Alignments.

__________________
'84 300SD sold
124.128

That could have saved you several hundred dollars and given you a new front end in the deal.

Well, true, but it already had an entirely new front end, for a very similar reason. The car was undriveable as it was, and I'd tried to diagnose the problem myself and missed it (the one part I hadn't thought needed checking), so it was either start randomly replacing parts to see if I could stumble upon the fix, or take it to my mechanic so I could enjoy driving the car this summer rather then spending every evening this summer working on it.

Yeah, it was expensive, but I'm not kicking myself for my decision, I'm enjoying driving my car this summer instead

And who'da thunk a UCA ball would so completely wear out in under 30,000 miles?

__________________
'83 300DTurbo http://badges.fuelly.com/images/smallsig-us/318559.png

Broadband: more lies faster.