I am going to be doing my engine mounts, tranny mount, and sway bar links this week. I am looking for the torque specs for the bolts on the sway bar links, the specs for the bottom bolts on the engine mounts, (I know the top bolts are hard enough to get to even with the tool, so ill tighten those as much as i can, And i believe the torque/order if i need to do anything with the steering rack to move it out of the way?

Also any tips on the mounts would be great, I got the tool and i got the Lemforder mounts.

2012 C250 Coupe, RWD


One more thing, can i tighten the sway bar links while car is in the air or does it have to be sitting on the wheels?

 

Engine mount torques

Sway Bar Torques
WIS torque values attached.

 

Thank you. I ripped of the head of a motor mount bolt but enough is sticking out where I can get a new one.

 

Stumbled across this thread whilst looking for rear sway bar link torque values.
Just wondering do you have a table for the rear sway bar link torque values?
Need to release the top rear sway bar link to get access to the top bolt connecting the rear caliper to the hub.

Thanks!

 

Sure....

 

Thank you very much!

 

Wow, 98 NM for the stab link bolts? That's a lot of torque ... 72 ft-lbs if my conversion math is correct.

 

When replacing the sway bar end links (with stock non-adjustable )

1. Does a new nut need to be used because the end links do not come with any nuts

2. Is it necessary to have the all four wheels on the ground with the car loading up the suspension? What I did was take off the wheels, the car on wood blocks, and make sure the end link bolts went in to the holes of the strut bracket and sway bar in their neutral position. By neutral position i mean the end link bolt was pointing at 90 degrees to the shaft of the endlink. To do that I had to jack the sway bar up so its hole would meet the bolts of the end link with the bolts sliding in easily and connecting flush with no play or gaps between end link and bracket/sway bar surfaces at the ends. With the car with 4 wheels on the ground the bottom ball bolt looks like it is has a slight upward tilt on the drivers side, but on the passenger side is horizontal flat to the ground.

The car drives better than ever- steering its tight and even on the both sides, drives straight, no noises, corners flat.

 

My opinion ... torquing bolts with weight of the car on the suspension is always the ideal method. But my links are noise-free by lifting the front end by the subframe, and then jacking the control arm just enough to get a neutral position for the end link bolt into the strut hole. Then put as much torque (98 NM, are you kidding?) as possible on that nut with a hand tool in that confined space.

Do the nuts have to be replaced? Good question .. on my 2014 they've been off and back on several times and only got loose and noisy once before I discovered the method described above. And I certainly was not getting 98 NM on them either. So jury's out for me, if they get noisy again someday I may try new ones, but for now all's well.

 

Thanks Tom.

On the BMW and GM forums they say the nuts are one-time use but that could be specific to them.

Yes to get 98 NM I'd think you'd need to hoist the car up and use the torque wrench from underneath. And damn were they hard to get off- we used anti-rust penetrating spray and also a nut freeze spray and it still took us about 3 hrs mostly trying to get the nut off to do what should be under an hour job.

I've seen recommendations of checking the nuts after 100km or 1000km depending on the brand of end-links

I did it essentially like you did- took the wheels off, jacked up the vehicle, and then used a small jack under one of the suspension arms to lift the sway bar to meet the end link. I found that it was really important to make sure the end link bolting surface sits perfectly flush up against the the strut bracket and the sway bar. Otherwise it leaves a small gap that doesn't close as you tighten and I suspect that results in some play and noise as the suspension moves over uneven roads and steering.

I found this post from someone who suggested a way to do it if it can't be done the ideal way ( after the fact, of course).

"Easiest way IMO - would be measure the centre of the alloy wheel to the arch whilst down on all 4’s. Jack the car up, put blocks under the sills (car must be level) remove wheels.. Jack under each brake disc - both sides at the same time, to simulate the car being on the ground, then match the measurement of the hub centre to arch, you took earlier.. Torque down top and bottom end link nuts with loctite, leave drop link loose, until ARB sits perfectly parallel to the ground.. Use copper grease on the threads and then tighten down. DO NOT over tighten as this destroys the threads inside the drop link"

 

Rather fiddly little thing, isn't it? Most ball joints we're familiar with have a taper below the threads that centers and aligns the joint ... but as best I can tell these don't, so it's all too easy to not get them properly seated before tightening.

As regards the nuts, I think they are what are called 'deformed' ... if you look closely two sides are slit and the threaded bore is not perfectly round. So as you tighten the but, it deforms slightly to accomodate the bolt's shank and thereby becomes locked (my Porsche uses deformed nuts like this, on that car the holes are literally oval, a strange sight when you take a long look!) I still think a locknut with nylon insert would work well in this application. I suggested using Loctite in a previous thread and that would probably work well too until someone went to take off the nuts in the future ... even blue Locktite would be hard to break loose.

I noticed the other day that my wife's Honda has stabilizer links with ball joint ends too, so Mercedes is not the only one doing this!