Flat towing a 1983 300SD behind an RV - PeachParts Mercedes-Benz Forum

ROLLGUY · #1 05-14-2013, 02:48 PM

Quote:

Originally Posted by t walgamuth

Attaching to the bumper is totally inadvisable. The bumpers fall off on their own due to corrosion.

I don't believe anyone suggested that the tow bar be fastened to the bumper, so yes, "Attaching to the bumper is totally inadvisable" is agreed.
Attaching a tow bar base plate (home made or otherwise) to the place where the bumper attaches (and more) is the only advisable way. A plate could be made that sandwiches between the bumper shocks and the frame and another separate attachment point made, and that plate welded to the attachment points of the tow bar. I am sure (if it were my car) I could design and fabricate a base plate that would be able to lift the entire weight of the car if need be. I am also sure there are plenty of other people that could do the same or better....Rich

t walgamuth · #2 05-14-2013, 07:47 PM

Quote:

Originally Posted by ROLLGUY

I don't believe anyone suggested that the tow bar be fastened to the bumper, so yes, "Attaching to the bumper is totally inadvisable" is agreed.
Attaching a tow bar base plate (home made or otherwise) to the place where the bumper attaches (and more) is the only advisable way. A plate could be made that sandwiches between the bumper shocks and the frame and another separate attachment point made, and that plate welded to the attachment points of the tow bar. I am sure (if it were my car) I could design and fabricate a base plate that would be able to lift the entire weight of the car if need be. I am also sure there are plenty of other people that could do the same or better....Rich

I am well aware of your skill in metal fabrication (

)....my concern is with the thin sidewalls of the shock tube supports.....on the other hand I have never had the bumper off a 126 so they could be thicker than the 123.....but without serious reinforcement I would take the bet about supporting the car by the bumper mount bolts on a 123.

Skid Row Joe · #3 05-14-2013, 08:31 PM

You're going to have to mount your brackets to the unibody, with re-inforcing plates under the bracket faceplates to tow the MB. It can be done, but would be a lot of work, versus just renting a trailer. I would definitely have brakes on the trailer, unless I was towing with an HD pick up, or 1 ton truck - and even then, I'd prefer trailer brakes.

ROLLGUY · #4 05-14-2013, 09:51 PM

Quote:

Originally Posted by t walgamuth

I am well aware of your skill in metal fabrication (

)....my concern is with the thin sidewalls of the shock tube supports.....on the other hand I have never had the bumper off a 126 so they could be thicker than the 123.....but without serious reinforcement I would take the bet about supporting the car by the bumper mount bolts on a 123.

All the MB's that I have seen have a tow hook in front, and it can be assumed that it is strong enough to pull the car not under it's own power. Yes it is a non-removable part of the uni-body structure, but it alone could probably hold the entire weight of the car if it had to. If you look at ALL of the base plates manufactured by the well known companies (Roadmaster etc.), you will see that they all use existing mounting points (bumper mounting points primarily)in addition to other mounting points that are perpendicular to the primary mounting points. Sometimes holes have to be drilled for the secondary mounting points. My "point" (is there a limit to how many times a word can be used in a thread?

) is, no tow bar mounting should rely on only one axis of mounting. If a tow bar had only bolts going fore and aft (for example the bumper shocks), it would be easy to pull them out in an extreme situation. As others have said, bolts and reinforcing plates in addition to the stock mounting bolts and points are very important. From the first post tomas_maly said:
"I am looking to find a way to long-distance tow my 300SD behind my RV (a school bus conversion) - and I think I'd like to flat tow it using a tow bar. The driveshaft will be disconnected (I can do this manually) so I'm not concerned about the transmission. I'm trying to work on the cheap (all my money is going toward the bus-motorhome to make it livable).
This is for long-distance travel so it needs to be safe and reliable.
Tow dollies don't seem to make much sense because you have to disconnect the driveshaft anyway. And towing the car backwards (front wheels on the ground) isn't stable above 25mph. A flatbed trailer is nowhere in my price range, not even used."
It seems to me that he is set on towing his car with a tow bar, so I am offering him MY support for his decision. I am not going to try and talk him out of towing his car any other way (as others are continuing to do). I believe it is the best choice for the least cost, but ONLY if it is done correctly by a competent fabricator. Just running some long bolts through the bumper with big washers is not going to cut it.....Rich