removed my rear subframe

[TJ 450]

No worries. I think that's the way to go (perhaps not the eBay bit though ). It will also be interesting to see if the new strut boots are textured or smooth. It's interesting how my new ones were rough.

Tim

[Big_Richard]

No worries. I think that's the way to go (perhaps not the eBay bit though ). It will also be interesting to see if the new strut boots are textured or smooth. It's interesting how my new ones were rough.

Tim

I'm assuming one has to remove the ball joints to replace the gators on the rears ?

Hopefully the australian dollar picks it self up again soon, NOT impressed at all with it only being worth 65c US at the moment.

[WGB]

I'm assuming one has to remove the ball joints to replace the gators on the rears ?

Hopefully the australian dollar picks it self up again soon, NOT impressed at all with it only being worth 65c US at the moment.

yes - I use two large spanners can't remember the size and one has been ground down a little to make it thinner.

Both my ball joints were snafu and both were removed with the two spanners while the body of the ball joint was held in a vise to reduce movement.

Both undid reasonably easily using the two spanners and I replaced the bellows but at the first attempt I only had one replacement so put both back but left the joint only loosely nipped up - subsequently replaced it without removing teh strut from the car using the two spanners and undoing teh two lower mounting bolts.

I think the lower ball joint at the rear is the same as the self levelling suspension one - but not sure - if so there should be a reasonable supply of second hand replacements.

Check for movement in the top mount as mine had about 1/2 cm clearance due to compression of rubber.

The 65c dollar is a bugger but I have just bitten the bullet and accepted that everything is 30% dearer and get on with it.

Bill

[TJ 450]

I have confirmed that the 6.9 version of the rear balljoint differs from the rear SLS version. The 6.9 version is much more heavy duty in construction for obvious reasons, although the SLS version may actually fit.
I will have the definitive answer when I overhaul the SLS system on my 450 in a few months time.

The SLS version is manufactured by TRW, whilst the 6.9 version is manufactured by Lemfoerder.

Removing the balljoints from rear struts is the proverbial piece of cake, two slim 22mm spanners do the trick. The fronts are the stubborn ones.

Tim

[Big_Richard]

excellent sounds like a plan.

I have 3 rear struts remember, the car came with a spare, all 3 have excellent ball joint boots, its a shame the front and rear balljoints are different, or are they.... perhaps the boots are the same...

[TJ 450]

The rear boots appear different, because there are actually set in the base with a pressed-in ring. If you examine the spare strut, you'll know what I mean. I would just replace the fronts, unless the rears are actually split, otherwise it will probably require experimenting with the spare or whichever has the most play out of the three.

Tim

[Big_Richard]

The rear boots appear different, because there are actually set in the base with a pressed-in ring. If you examine the spare strut, you'll know what I mean. I would just replace the fronts, unless the rears are actually split, otherwise it will probably require experimenting with the spare or whichever has the most play out of the three.

Tim

with your experience, do you think the KOK brand boots offer a satisfactory level of inner peace when it comes to protecting those costly balljoints?

[TJ 450]

In short, no, not for the rears. This is due to the fact that they would be exceedingly difficult to service. It would be much better to source polyurethane equivalents.
IMHO, the KOK ones are OK for the fronts, because it is more-or-less a conventional setup, but again, polyurethane would be better than black rubber.
The original Lemfoerder lower balljoints have polyurethane boots. FWIW, I think the material is more resistant to chemical attack from hydro fluid, etc.

Edit: Perhaps Malz even have polyurethane versions... it would be impressive if they did.

Tim

[Big_Richard]

hydro fluid protects rubber

spheres wouldnt last too long would they 

What i find fascinating about the struts, particularly on the fronts, they are $1100 each as a complete assembly.

the balljoint alone is worth $700
the top rubber mount is worth $140

By my crappy maths, that business part of the strut it self is only worth $260

How the hell is the balljoint worth over 2.5 times the worth of the strut itself 

[TJ 450]

hydro fluid protects rubber

spheres wouldn't last too long would they 

This is getting technical, but I think it has a lot to do with the type of rubber/plastic. Hydro fluid dissolved the leveling valve boots on my car, although there was probably heat from the exhaust system involved too. The trick would be to determine the composition of the sphere diaphragms and get balljoint covers of the same type.

When I was investigating replacing "those things", I was quoted a similar figure. I was then told by multiple sources, including the Classic Center USA, that they are now only available with the struts as a complete unit.

I don't know what the logic is with those prices, but I certainly would have thought a strut was worth much more than a balljoint. It seems to me that they simply don't want to sell them separately.

Tim

[s class]

Just buy new struts, then you don't need to worry about the maths

Seriously though, in the last few months I have driven both my 6.9's back to back a few times, and I am now convinced that strust should never need replacing.  The red car's struts (at 195 000km) feel the same as the blue car's new ones.  I had to replace the ones in the blue car because someone had butchered them. 

[TJ 450]

Seriously though, in the last few months I have driven both my 6.9's back to back a few times, and I am now convinced that strust should never need replacing.  The red car's struts (at 195 000km) feel the same as the blue car's new ones.  I had to replace the ones in the blue car because someone had butchered them. 

That's a very useful comparison, s class. I can imagine that the front struts might get wear from dirt if driven over unsealed roads all the time. Otherwise, I would also think that they should last a very long time. They are very well engineered units.

Tim

[Big_Richard]

Just buy new struts, then you don't need to worry about the maths

Seriously though, in the last few months I have driven both my 6.9's back to back a few times, and I am now convinced that strust should never need replacing.  The red car's struts (at 195 000km) feel the same as the blue car's new ones.  I had to replace the ones in the blue car because someone had butchered them. 

I had a feeling this might be the case - im not 100% convinced the struts actually do anything at all by way of damping. If you remove them from the car and move them up and down by hand all they seem like is a hydraulic ram.

[peterq]

Patrick
I will be taking the rear of my 6.9 to pieces soon to fit new boots to the struts (original MB parts I've had for about 5 years waiting for me to get a round tuit), new rotors (only 4 years in the cupboard) and handbrake fittings. I was about to get new flexi hoses for the brakes, but if you have some steel wrapped ones available I'd prefer to use them. I or my wife are in Perth every few weeks, please send me an e-mail to sort something out.
I replaced the front struts a couple of years ago, I *think* it improved the ride but for the two weeks the car was being worked on (part time) I was driving a decrepit Ford Courier ute with no semblance of suspension so when I got back into the 6.9 it was difficult to tell.

[WGB]

I had a feeling this might be the case - im not 100% convinced the struts actually do anything at all by way of damping. If you remove them from the car and move them up and down by hand all they seem like is a hydraulic ram.

I suggest you read the M-B Document  "Introduction to Hydropneumatic Sispension" which covers damping in about 1 sentence.

Damping is controlled by a plate on the strut piston with several holes in it which restricts the flow of the fluid on rebound and to work it requires a free flow of fluid which is why the damping effect is lost when the speres go flat.

Bill