Mercedes GLK 250 Towing Experience

A while back I wrote about what it’s like to use a Mercedes GLK 250 as a tow vehicle, and promised that I would do a follow-up once I’d finished a big trip I’d planned that would involve me towing a big camper trailer around the country.

Well, that trip has come and gone, so it’s time to give my final thoughts on the towing experience when using a Mercedes GLK 250.

For reference, my vehicle is a 2014 Mercedes-Benz GLK 250 Bluetec – meaning it has a diesel engine, a 2.1 liter twin-turbo diesel engine to be specific. It doesn’t have a huge amount of horsepower, but it has gobs of torque (as you’d expect from a diesel).

The big road trip I mentioned in that original post was quite an adventure, and although we ended up taking a different route than originally planned (and so I didn’t get to test towing up any mountain passes), we did cover a lot of miles, all while towing a roughly 3,000 lbs “teardrop” style trailer.

Throughout the entire trip, the GLK performed flawlessly. We tackled big highway stretches where the speed limit was 75 MPH, and it had no trouble at all reaching that speed and holding it for hours and hours on end. Even at these high speeds the engine was not over-revving (thanks to the 7-speed automatic gearbox), and all coolant and oil temperatures were right where they should be. As far as handling, it was perfectly stable, even out in the plains where the wind can be a problem for high-profile vehicles (the trailer we were pulling may have been teardrop shaped, but it was quite tall – taller than the GLK by about a foot or so). We never had any issue with trailer sway either (I am always very careful to load my trailers – no matter what type – properly to avoid this problem.)

Later in the trip we wound our way up some back-roads up into the Blue Ridge mountains – and some of those roads were both fairly steep and very twisty – and once again we had no trouble at all. The little diesel engine always had plenty of torque to help get us moving, and because we weren’t very long we had no trouble managing the tight curves.

Parking and maneuvering with the trailer attached was also very easy – even though the trailer was so tall I couldn’t see over it (something I’m used to being able to do with the utility trailers I usually pull). I had to back into a number of camping spots, and with a little help from my wife as a spotter I had no trouble getting the trailer where I wanted it to be. The side mirrors on the GLK aren’t huge, but they aren’t small either and I could see what I needed to when backing up. The good visibility out the rear windows also helped.

Really the only thing that wasn’t ideal was the brakes – the GLK doesn’t have any built-in capability for connecting a trailer brake module (you could maybe hack one in, but it’s not designed for it – despite having a 7-pin connector). We had a Bluetooth trailer brake module on the camper trailer, so we did have assistance with braking, but it was not that great – adjusting how much braking force it was applying wasn’t easy, and more than once we had the trailer brakes set too high for the type of braking we were doing, and the brakes locked up on us – not a fun experience. Managing this wasn’t easy – you almost needed a passenger to help manage it for you (which is what we did – whoever wasn’t driving would adjust the trailer brakes as needed). A hard-wired proportional brake controller would’ve been much better – but again, as I said the GLK isn’t wired for it from the factory (even with the factory tow hitch). Maybe with a better or newer Bluetooth brake controller the experience would’ve been better, but that’s how it went for us with the one that came with the trailer.

Still, this was really the only downside – and if I owned a big trailer like this and used it frequently, I’d find a way to get a better brake controller. But for our purpose – just the one trip – we managed OK with the Bluetooth one and the app.

Since that big road trip I’ve also gotten a trailer of my own – not a camper trailer, mind you, but a small utility trailer. So I’ve spent a lot of time towing things with it – it is a very useful thing to have around!

I’ve pulled trailer loads of mulch and dirt with it, as well as lighter things like taking a large load of recycling to the recycling center in town, or picking up lumber & supplies from the local hardware store. Nothing I’ve towed has come close to being as heavy as that camper trailer we used on the road trip, but I’ve pulled some decently heavy loads – and once again, the GLK has proven to be a very capable tow vehicle.

Overall, the GLK works very well as a tow vehicle – though for heavier trailers it’s not as great due to the brake controller stuff I mentioned. Likewise, it’s great when pulling shorter trailers (16 to 18 feet long); but longer trailers would probably start to get a bit troublesome due to the shorter wheelbase of the GLK itself. But within those small limitations, I wouldn’t hesitate to recommend using the GLK as a tow vehicle.