Towing with GL450
Looking to hook up the car trailer for short (<100 mile) trips to the track, a near 7k load.
Certainly not lookIng or expecting to set any speed records, more concerned with airbag handling of rear squat and overall stability at highway speed.
All GL's are rated to 7500lbs, but I've been down this road before with other trucks and that doesn't always tell the entire story.
Load the car as far to the rear as possible and put it on backwards if it's a nose heavy car.
I recall reading how to rig up two bathroom scales to somehow do it, but it seemed very convoluted, a large PITA and of questionable accuracy. Besides, with a 7000# trailer (including the load) I'd be very surprised if your tongue weight isn't far in excess of 600# so you'd probably break the bathroom scales on top of not getting an accurate reading.
I'll report back.
Gotta look into this further as it doesn't make sense to me they would rate the tow at 7500lbs and give you an 8% tongue limit.
Trending Topics
I wouldn't worry about 100# over weight if it was me. There is so large a safety margin build into these published limits that another 100#s can't possible make much difference. Although the farther out of spec you are on the receiver to ball shaft distance (and you are), the worse that 100# overage is.
And if your loaded trailer weight is anywhere close to the 7000# you mentioned earlier, I'm shocked that the tongue weight is only 700#...how did you do your measurement?
The Best of Mercedes & AMG
I know other German SUV's like Porsche, VW, and Audi explicitly ban weight distribution hitches in their manual. Mercedes does not seem to do so.
The photo of your dogs is nice
I know other German SUV's like Porsche, VW, and Audi explicitly ban weight distribution hitches in their manual. Mercedes does not seem to do so.
The photo of your dogs is nice

This is of interest, as well: https://www.etrailer.com/question-64347.html
With the GL, only one tongue weight is given in the manual and on the hitch, itself. The limit is 600#. If additional tongue weight were allowable, there would be a second tongue weight rating.
Then there is the issue of MB specs 7.5" as the maximum length from the center of the hitch pin to the center of the ball shaft. There isn't a weight distributor in the world that short. It's hard enough to find an ordinary hitch that short.
No one lists a 2015 GL450 trailer hitch being available. There are 2013 units available, as well as 2014, but even those are different from year to year. Need to dig further and see if 2014 is compatible with 2015.
Dealer wants $2800 for one ... lol
The other good thing is that there are extensive WIS install instruction - from A-to-Z including the full wiring connect - including running the retro kit harness up to vehicle front.
I believe - not installed/confirmed yet - you get full MB hitch function including COMAND call out - anti-see/saw, etc.
The bad thing - for the whole job - WIS labor is estimated at 8 shop hours - and that's the rub..
Thanks for the info fab.
Edit:
I now see why they quote 8 hours for the install. The factory kit requires removal of seats and dash, not something I'm looking to do.
I need to find an aftermarket kit for now.
Last edited by Mike450; Jun 24, 2015 at 10:35 AM.
Curt Manufacturing part number #13190 for the 2014 GL carries over to the 2015.
I'll deal with the wiring and trailer system over the summer. Need the hitch for bike rack now.
And for anyone reading this wondering if they should order their truck with a hitch, the answer is YES. The receiver alone is costing me $350 installed. Wish I would have thought of this 4 months ago.
Last edited by Mike450; Jun 24, 2015 at 11:41 AM.
What I would do is to weigh your setup with trailer attached at a truck stop. If you are not exceeding the rear axle rating (and GVWR), then I would try it out with no weight distribution hitch. Just keep your speed a bit lower. My 2 cents.
We just got a 2015 GL450, to tow our Little Guy Tag (basically a rolling King Sized Bed with a kitchen in the back). I currently tow with a 1999 F350 diesel (3 horse slant load GN) and would love to downsize into a small BP as we only have one horse now. Any suggestion on brands of horse trailers to look at for short hauls? The 450 towed the Tag perfectly, never even knew it was back there (once we got the adapter for our LED lights).



