MBKLUE

That might work then. If the spring failed due to rust the shock bolt might be "frozen" in place so there could be little rotational force applied to the 1/4 inch drive side as you turn through the initial very high resistance.

calder-cay

Do we need a socket? (there are 1/4 to 3/8, and 1/4 to 1/2 adapters). It seems an appropriate wrench size would do ... or maybe an appropriate offset wrench would do. After wrenching on cars and motorcycles for 50 years, I've learned to buy what's needed - now I have too many tools I'll bet I have a socket required, so are available. ... (update) now I see what's required, an M12.

I did watch the video ... is it the shock's lower thru bolt and nut that is the challenge??

TimC300

I replaced the springs in my W204 which is similar or even the same. I just disconnected the inner side of the spring control arm and lowered it with a jack. M12 triple square for the bolt. I think because theres alot of tension on the bolt it wouldnt simply pull out, I used my impact wrench in reverse to spin it all the way out, by hand would have taken forever. After the bolt is out just slowly lower the jack all the way and the spring can be pulled out. I didnt disconnect anything else. The bottom shim in nickel plated and were worn to nothing so I replaced them as well. i had to get creative because the exhaust was in the way thats why I got the stubby M12, could fit my 3/8" ratchet and socket to hold the bolt while removing the nut, then used a long extension angled a little to remove the bolt. I reused the same nuts and bolts.

I replaced the rusted springs with a used set in very good condition I found cheap on eBay.

John CC

Thanks! M12 triple square. I wasn't sure.

The shock bolt has a head that looks like a torx driver. I have a set of 1/4" drive sockets that fit. The 3/8" drive version is out of stock in that size. I have a 1/4-3/8 adapter but I'm concerned I'll twist the 1/4 drive off.



But you're saying I don't need to take the shock bolt out. That's good, because having the control arm attached at two points will make it more stable.

John CC

@TimC300 Did you have any trouble getting the control arm jacked back into position? It looks like you have the jack inboard of the spring seat. Is that correct?

TIA,
John
Wow! I've got 2 broken and know where there's 2 more badly rusted. Good used has to be a find!

I got two new from Sachs for $102 shipped.

I'm not sure, but I think those lower shims might be aluminum. They're awful soft... I ordered new rubber spacers on top, too, so I'm about $140 plus tools into it.

TimC300

I did not need to disconnect the shock. I was able to remove the spring with the top rubber shim still attached.

Only reason I got the 3/8' triple square is its stubby to fit the close to the exhaust, or I would have just gone with a 1/2" drive one.

I was using my smaller floor jack to lower the control arms so thats why I used the wood. I wanted to make sure i was putting even pressure on both sides of the control arm arms so they wouldnt flex and misalign the bolt holes.

To reinstall I just positioned everything to where i thought it would line up when jacked up, I had to reposition a few times to get it right, then it just jacks into place easy enough.

Im always searching ebay for good deals on things I may need. I like a specific seller Labur Parts, they have good looking parts and list the mileage of the car they were removed from. I paid $55 and they looked almost new with 40k on them. I bought a set of rear shocks from them with 40k on them for $95.

Heres an example of the condition of the parts they sell. These say they have 88k on them.

John CC

Interesting! Looks like they're in Northern California. My springs have less than 88K and they're both broken. Must be the NE winters.

calder-cay

I was curious ... so checked our 2001 Jeep Wrangler, with 136,000 miles - has coils at all four corners. Zero rust or ANY sign of deterioration.

Is this indicative of your location?? We are in south central Texas. I shall check the GLK tomorrow (92k).

TimC300

Im guessing its the road salt/chemicals they use in winters is corrosive and just eats away at paint and coatings.

I replaced the springs just because how rusted they looked, i was afraid they would break while driving. Even the spring control arms are rusted so ended up buying a used set in great condition to install, the metal shims at the bottom were disintegrated to nothing. Thats why I like buying used parts from California, they look great compared to whats on my car. I replaced the shocks this past winter and couldnt believe how much salt was over everything under there.





Heres why I used the block of wood under the control arm, the jack i used is small and I wanted to make sure both arms were supported. Also I think the subframe sticks down a little right under the bolt.



I am always searching ebay for good finds. I was looking for spring arms and came across a set of all the control arms cheap, I needed the rear emergency brake cable and dust shields and came across an entire wheel carrier assembly cheap so picked it up. Less than the price of new Mercedes parts and now I have a bunch of extra stuff if i need it. I updated the struts, springs and shocks for less than the cost of 1 new Mercedes strut.

I made a thread listing some things ive done. https://mbworld.org/forums/c-class-w...uspension.html

Silver Shadow

The many bolts on a Mercedes that look like Torx are called E-Torx. Torx is internal and E-Torx is external.
I bought a set of E-Torx soon after buying my MB.

TimC300

I never needed torx until I got a Mercedes. Never really needed metric sockets either. I bought a nice set of the torx sockets though mostly use E10, E12 and E14. Im planning on replacing a cv boot and the axle bolt is an E24 which is in the kit which is convenient. The best thing about the kit I have is it has all the socket adapter 1/4-3/8, 3/8-1/2, 1/2-3/8, 3/8-1/4 which im always seeming to misplace.

Another thing I also picked up that I never owned before was a cordles impact wrench, I now use it almost every time i work on the car and saves so much time. Its so compact it fits almost anywhere. Its one of those things i cant live without now especially in my older age. Got it on eBay new pretty cheap then bought the charger and 3ah battery. When I first got it I couldnt remove the lug bolts with it and thought it was weak until i bought a torque wrench and realized i was putting them on way too tight, at 98 ftlbs it zips them right off. Makes suspension work easy. First time i changed the rear differential fluid I couldnt get enough level laying under the car so put the impact on the plug and loosened it right up.

Never torqued nuts and bolts down before either until Mercedes. Bought the cheap Harbor Freight 1/4, 3/8 and 1/2 set and torque everything down now. Keep the 1/2 in my trunk specifically for the wheel bolts. i did have a problem with the 1/2 which never seemed to work right so went back to Harbor Freight and they let me exchange it for another one.



The one I bought was new in the box and I didnt buy it off this seller but was the same tool.

TimC300

I knew i saw the recommendation to replace the lower shims when the springs are replaced. Its in the listing for the spring part #'s.

They are thin and basically form to the spring and control arm.

John CC

That part is made of unfinished aluminum. Who in their right mind would sandwich a thin piece of aluminum between a steel spring and a steel control arm? And, it doesn't seal anything.

John CC

Quick update: I got one side done. I ended up taking the lower shock bolt out, too. The hardest part was getting the inner control arm bolt holes lined up. I didn't realize at first the bushing in the subframe is not level.

TimC300

The shims are zinc and it says it is part of the "improvement in corrosion protection". I read it in the W204 training manual, should be the same in the GLK since they share the same spring control arm its in. https://www.mersec.net/244/improveme...ies_w_203.html

John CC

Interesting. I grew up in an area where zinc was big business. Never saw anything that didn't look gray. I stand corrected. They look and feel a lot like soft aluminum, which, as a retired aircraft mechanic, I'm also familiar with. Aluminum in contact with steel, especially in a situation where there is relative movement, is a formula for disaster (for the aluminum). Zinc is more active than aluminum, so is supposed to be a sacrificial element. Mine were about 90 percent corroded. They don't last very long, at least in the NE. And, judging from the apparently common problem of broken springs, it doesn't work! OTOH, maybe it does explain why you were able to land good used parts from CA.

Still, it doesn't seal anything!

John CC

Ah, E-torx. Now I know what to look for! The 1/4" drive worked fine. Actually, the 9mm socket fits the bolt for the sway bar link. The shock bolt took an 11mm socket, but it didn't need much holding to get the nut off.

TimC300

I think the torque specs were already mentioned. I marked up my drawing for quick reference to have on hand. The manual has the # for the specific spring compressor, which is expensive.

John CC

Well, I got it done. I ended up taking the shock bolt and the inboard control arm bolt out. I had a clone of the Mercedes compressor, but I couldn't get it to work. I don't think it is intended to remove broken springs. It might work fine on an intact spring, and it might have worked to install the new ones, but I couldn't use it to get either broken spring out. In trying I had another issue, the screw that compresses the spring extends out of the top of the device, and eventually contacted the plug in the center of the upper spring perch, and punched a hole in it. I couldn't find the part in the EPC, but I think it is a 40 or 42mm plug. I put an inner tube patch on one side and duct tape on the other.

The hard part was getting the control arm back up and aligned with the bushing. You have to alight it front to back, inboard and outboard, and the hole in the bushing slopes from front to back, so you're jacking the control arm up while compressing the spring and dealing with three different degrees of freedom. The bolt goes in from back to front, so I finally made a drift the same diameter as the bolt. I got the front side to line up and stuck the drift in the hole from the front. Then moved the jack slightly to align the rear side hole and ran the bolt in the hole, pushing the drift out.

All in all, a huge PITA.

MBKLUE

Sounds like less fun than drinking cold beer on a hot summer day.

John CC

Slightly...

TimC300

Its probably easier on the C300 with its shorter suspension, GLK must have longer springs so more clearance is needed.

I seem to remember when doing my springs I had to push/kick the bottom of the wheel carrier in to align the bolt holes. Think I used a long Philips head screw driver at first to help align it then drove the bolt through. I used my impact to remove and install the bolts, they wouldnt just pull in and out for me at least.

Did you have both sides jacked up off the ground? I removed the springs twice because at first i installed the top rubber shim that came with the replacement springs but it was the wrong one, they were 13mm and my car came from the factory with 9mm shims. I wasnt even paying attention, ended up having to put the original shims back in because there was a noticeable ride height difference, larger gap in the wheel well. Anyways, the first time replacing the springs i just had one side jacked up and removing the spring was a pain, the second time I had both sides jacked up off the ground and it seemed to go easier, I think because there was no tension on the sway bar links the spring arm was able to drop lower.

When I replaced the front sway bar links I learned to have both wheels hanging off the ground, or else there was tension on the sway bar links and had to work at aligning the bolts by raising the wheel carrier with a jack.

calder-cay

"... the second time ..."

Wow, you've had to replace the springs TWICE - on the same axle?
If yes, was one replacement because of breakage? Or just because of mileage?


(sidenote: my wife had a 2001 E320 with 330,000 miles and never had the springs replaced).

John CC

Could be. They are pretty long.

Once the spring was compressed there was no moving anything on the jack. I used an alignment punch to get the front side aligned and put the drift in the hole, then got the rear side aligned and put the bolt in. I think the fully threaded bolt withthe pointy tip was chosen to allow that. There are no threads in the holes, but it does help pull the bolt through and get that last bit of alignment as the bolt pushed the drift out of the hole.
Yes, for most of the job. I put the tire on one side and lowered the jack before I re-installed the bolt on the other side, just so I'd have something constructive to do before my helper came back. It may have even made things slightly easier.

Ouch! There are nubs on the spacer to identify them. GLKs have three nubs.

TimC300

The replacement springs I bought also came with the upper rubber shims that looked in new condition just like the springs so I installed those. Then when I was done and lowered the car on the ground there was a noticeable height difference and the car looked jacked up, much larger gap between the tire and wheel well. I took a good look at the old shims and noticed they were the shorter 9mm. It made no sense since in all my research I kept hearing 13mm shims are the correct ones. So I drove to the Mercedes parts dept and had them look up my VIN where they verified it indeed came from the factory with the 9mm shims. But now it makes sense since I have the sports suspension. So I had to remove the springs again to install the 9mm shims. I will say the second time took me no time at all since i knew what I was doing.