How do I tell which steering links are bad? - PeachParts Mercedes-Benz Forum

okto · #1 01-07-2014, 01:57 PM

My E320 has been getting kind of wandery, and last time I had it up on the jacks I noticed there was some lateral play in the steering.
What should I look for to figure out which links are bad and need to be replaced? I can't afford to shotgun it and buy one of everything right now, so I need to be able to triage it.

mpolli · #2 01-07-2014, 02:16 PM

Checking the tie rod ends is fairly straightforward. With the car on the ground and the parking brake on, grab a front wheel at 3 O'clock and 9 O'clock and try to move it "back and forth." Observe, or have someone else observe, the tie rod ends for looseness. What you would see is one side of the joint moving but the other side not moving. There are inner tie rod ends and outer ones. One or the other or both could be worn. The wear is usually the same on each side (R and L). Sometimes they are replaceable individually and sometimes you have to get the whole assembly (drag link). For example, on my car I can replace the outers, but for the inners I had to get the whole drag link/steering link.

okto · #3 01-08-2014, 04:26 PM

Excellent, thanks! Should I check idler arms too?

JamesDean · #4 01-09-2014, 01:02 PM

Just throwing some numbers out there..

To replace all three tie rod assemblies you're looking at $125 in parts roughly.

$40 more for idler arm bushing.

DieselPaul · #5 01-09-2014, 01:06 PM

Since you have to pay to align the car, I generally replace both sides even if just one side is bad. Paying for a second alignment down the road when the other side goes isn't fun.

I find that idler arms are generally overlooked because a lot of people do not know the cars have them. I've seen some real improvements out of idler arms alone on higher miled cars. For the $40 I would attack it as well.

JamesDean · #6 01-09-2014, 01:44 PM

For the cost.. I would take on replacing the center drag link as well. Its like $40-50. I've overlooked it on all my cars for a number of years... Finally did it on my 300D.

okto · #7 01-09-2014, 05:49 PM

Thanks for all the replies, y'all. It's been rainy and my parking spot isn't paved, so I haven't had a chance to look at it.

I've been paying closer attention to it while driving the last few days, and I would say that it isn't so much a constant waver in steering direction as it is an intermittent, sudden slight pull one direction or the other. It's not the lateral scoot that happens when rear links are bad, I've felt that, it's definitely a steering motion. Also, when I let go of the wheel, it tends to track straight for a good while, then it will tic slightly one way or the other. The problem disappears completely in turns, I assume because the steering system is being "snugged up" so to speak by the lateral force on the wheels.

I don't know if any of this helps diagnostically, but I'm always mindful of people finding my posts years down the road so I like to be as thorough as possible!

Hirnbeiss · #8 01-10-2014, 08:22 AM

Don't forget to check the ball joints.

JimFreeh · #9 01-10-2014, 10:24 AM

Also consider that there may be play in the steering box.

Have someone slowly turn the steering wheel and observe the lag before the pitman arm moves.

You can adjust out most of the steering box play.

Jim

MAVA · #10 01-10-2014, 11:09 AM

Moog suspension parts which are high quality(the professional grade is the very best), but most of their stuff is made in USA, Germany, and a few other quality country's.

To help you, look at the Vehicle Diagnostic Center portion of the web site.

MOOG Steering & Suspension | The Problem Solver

They make parts for your E320...

Moog-Suspension-Parts.com - A Dealer of the Federal Mogul Brand of Suspension Parts

I think your E320 has the rubber strut towers like a Mercedes R129 convertable, and I used Moog parts, and the towers were made in Germany, no made in China like URO parts...

Best of luck,

Martin

okto · #11 01-14-2014, 01:54 PM

So I gave the wheel the old 9-and-3 wiggle, and it definitely moves about half an inch at the outer edge of the wheel and clunks pretty loudly at the end of each movement. I'm worried that sounds more like a ball joint than a tie rod.

Any feedback/ideas? Since mine is a 95 I have to replace the whole LCA, and that starts to get expensive...

mpolli · #12 01-14-2014, 02:04 PM

Wow. That's a lot. Your ball joints won't wiggle with the car on the ground. I would bet that's tie rod ends. It is easy to tell by either looking at the tie rod end while some one does that, or putting your hand on the tie rod end and you can feel one side moving while the other is not. Your ball joins may be bad as well, and other parts too, but to test ball joints you need unload the force on them. It is a little more involved test. I am not sure the best way to test those.

okto · #13 01-14-2014, 02:49 PM

Oh dang. I gave it a closer inspection and the inner left tie rod end is indeed toast. At least half an inch of axial movement when I wiggle the wheel, with zero attending movement of idler arm or center link.

I raised the car off the front left wheel and it has the tiniest bit of 12-and-6 movement, small enough that I can't see it but can feel a tick at each extreme. Could still just be the tie rod, I'll report back after I've replaced them this weekend.

mpolli · #14 01-14-2014, 03:06 PM

OK.. Now here is the part where I will be called the most insane lunatic ever known to history: You can definitely adjust the toe in yourself. There I said it. Now there are many people who believe anything to do with alignment is a holy sacrament that should only be performed by a high priest trained in the very secret rituals of this ancient practice. However, if you are changing your own tie rod ends you will at least have to get the toe in good enough to drive it to the shop, and if you can get it that good then you can take it the rest of the way. There are different ways to do it, but the first thing I will tell you is before you start the repair, put the steering wheel centered and "sight" down the side of the car on one side then the other, looking for how the edges of the front tires line up with the edges of the rear tires (on each side). This will give you an idea how they should be when you are done. Obviously with the wear you have it will be off a bit. The best bet is when you are done get them lined up straight (assuming same track dimension front and back and same tires.) Then if you really want to get picky and set the toe then we can go from there. Yes there is the holy pusher bar etc etc. I made one out of 2x4's but I didn't notice much difference using it or not. And yes I have put over 100K miles on tires and they wear perfectly even. There is no magic to alignment and you can do just as well, working slowly with simple equipment, as a shop can do working quickly with expensive equipment. It does help if you know trig however.

mpolli · #15 01-14-2014, 03:09 PM

Quote:

Originally Posted by okto

I raised the car off the front left wheel and it has the tiniest bit of 12-and-6 movement, small enough that I can't see it but can feel a tick at each extreme.

I suppose that could be wheel bearings also. I think ball joint testing usually involves a pry bar.