I am not 100% sure but i think the SLK is not homologated for towing. The SLK was never designed for towing. I would ring MB about this. Does it have a towbar fitted.
The witter web site agrees with you they do not sell a towbar for them and say Not Homologted for towing against the SLK.
------------- Bill
For a licence dated 1997 or later you must add together the plated max weight of the caravan and trailer, if the total is 3500 or less you can tow it. You may even tow a caravan with a MAM greater than the cars unladen mass the restriction was removed in 2013
If it's pre 1998, the regulations are not as strict. You do not need a type approved tow bar. I would say it is plenty heavy enough and has plenty of power. I used to tow with a 2 litre Merc 190E and it was a fine towcar, even if traction on grass was a bit dubious.
I would imagine the SLK is about as far away from a decent towing car ever made - if the people who know about these thing say its not fit for purpose well I would tend to agree.If you had an accident- and sincerly hope thats not the case,I dont know how your insurance would stand up.
I expect Mercedes never bothered to equip them with mountings for a tow bar as they didn't expect their owners to want to tow with it. This is very different from saying it is not fit for the purpose.
If it is pre 1998 then a towbar does not need to be type approved and many manufacturers did not fit specified mounts. When the legislation changed they just elected to use existing holes etc to be nominated as towbar mounting points.
The SLK is one of the heaviest two seaters around and one of the most powerful. I see no reason why it is not capable of being one of the best towcars around if it can have a towbar fitted legally.
The OP has not stated the year of the car, so speculation is irrellevent
we stay at river breamish cc site and there is always a man towing with a slk,he tows a fair size van as well because i thought it couldnt tow it,i first thought somebody must of brought the van up for him,but then saw the reg plates match and ive seen him towing it a few times now
------------- please dont think im mad,im just different
I used to tow with a triumph stag,.I was told it would overheat/ not suitable for towing/ would be unstable.it was none of those, great towcar v8 3 litre with overdrive on 1st 2nd and third gear would go anywhere.I had a towbar made for it.16 miles to the gallon towing was a bit off putting. but when the sun was shining with the hood down it was well worth it .