CJBROWN

My CURT hitch is due any day. I did get the wiring module and installed it. I was glad I did some research on what is involved as these cars have an unusual electrical setup for the stop/turn/park lights. And since everything is computer controlled most owners and in fact most shops will not touch them.

You can't just tap into the lighting wires like most cars as the stop and park lights are on one circuit. They call it a PULSE MODULATION SYSTEM so you need a converter to output seperate stop and park lamp lighting for your trailer lights. The CURT product is powered so there is no draw on your light circuit in the car. No heavy duty flasher required. The unit just uses the car's lighting circuit for a signal, then it supplies the power for the trailer lights from it's own 12V power lead.

Their product number 56200 described here: http://www.curtmfg.com/index.cfm?eve...&categoryid=57


You can get them for $60 at rockauto.com

The GLK has a 12V power socket in the cargo area and it's switched with the iginition, so this works out perfectly. Tap into the power lead with the supplied scotch-loc. The socket has a threaded ring retainer on the back of it so it can be pulled out for easy access to the wiring. Don't forget to run your modules power lead throught the retaining ring before you connect it - don't ask me how I know. I ended up extending the power lead so I had enough length to route it nicely back there and ziptie it to the power socket's wiring harness. You may want some extra wire and a butt-connector and crimper. Most DIY'ers have an electrical connector and crimp plier tool pack on hand.



The switching module can be mounted in the compartment where the power socket is. And there's a grounding stud on the wheelwell in there making it easy to attach the ground wire for the module. I ziptied the module to the foam tool tray portion that looks like a can-holder inside there. If you remove the left taillight cover door everything is easy to get to.



The top wire of the taillight connector is the stop/park circuit. The second wire down is the left turn signal. The module has a long wire for the right signal that is easily run across the back of the spare tire compartment alongside the other wireing harness for the righthand lamp set. The second wire from the top of the right hand lamp assembly is the right hand turn signal lead.

The 4-pin trailer connector can be run under the sill where the right hand signal lead goes. At the back of the spare tire compartment on the right hand side is a rubber plug. Removing it lets you route the trailer connector down the inside of the rear valence and out the back of the car. The rubber plug can be split, the wiring run through it, reinserted and sealed with a dab of silicone sealer. Tie everything down with zip-ties, and you're good to go. Total cost - $65 with shipping for the module.



The part that took the longest was figuring out what to connect to. The actual install then took just minutes. And it works perfectly!!

I'll get some pics and post here, and then an update when the hitch gets installed. I found the CURT model 33059 hitch for the GLK on Amazon for $193 shipped. It's enroute.

So much for the $2500 trailer hitch install from a dealer - forget that!!

Spooner

Great post! I am just trying to track down the right glk and most don't have the oem hitch so I really needed this info. How do you like hitch, does it look ok?

CJBROWN

The hitch arrived today. It's very heavy duty, precisely made, and with a high-gloss powder coat finish. Very nice. It bolts to the main bumper braces and a crossmember in front of the spare tire well. Shouldn't be too hard to install. All in I'll have about $260 in the setup. Pics coming.

My utility trailer has a spring-over axle setup for offroad, it normally tows behind a 32 motorhome with a 3" drop hitch. For the benz I have a ball mount insert with a 6" drop that I will turn over to raise it to about 19 inches off the deck so my trailer will run level. Can't wait to have a replacement for the pickup truck I sold (Duramax). At least I can haul my motorcycles and get to depot for building materials or whatever. Always tinkering.

EDIT: BTW, I just noticed your user data and your bikes. I ride a Kawasaki 650 Versys on the street and a KTM 250XCFW offroad. My son has a new WRF250F. And I just sold my 03 Duramax Diesel. You have great taste in motive power! The little benzo drives fantastic. It's so quiet you can't feel or hear it running. And it's just heavy duty enough to be a versatile SUV. It has to be one of the nicest cars I've owned.

Spooner

Haha, yep my Duramax goes to it's new owner in the morning. I will REALLY miss the truck and if I could justify keeping it just for throwing the bike in the bed I would keep it but my house will start looking like a used car lot and I wouldn't really drive it all that much. I am still nervous to tow with the GLK though. After towing with a Diesel Excursion and the Chevy you really get spoiled! Looking forward to the pics of your setup.

CJBROWN

I was in the same boat, so to speak. Sold our Grady White last year and the truck was a fifth vehicle, sitting on the street, making a $400 payment. So that didn't make sense. Told wifey if I'm gonna make a payment on a car it may as well be something I want to drive. The truck was an LT, was basically a Cadillac inside, but they ride like a buckboard and too big to park at the store. Oh well. The only thing I miss are the heated seats. I got $23G for mine, was cherry. No more injectors to have to worry about!

The GLK will do fine up to a couple of thousand pounds. I figure two bikes on the trailer is about 1200-1300. Will be perfect. The downside is you can make 75 with the bikes in the truck box, might get a ticket for that with a trailer in tow.

Okay, back to our regular programming.

KenNinBC

Thanks for the wiring info ... I'll probably get the same kit sometime down the road. I've already installed the Hidden Hitch - mostly as a bike carrier so no need to install wiring at the moment.

Pix here:

https://mbworld.org/forums/glk-class...nally-got.html

I chose Hidden Hitch over the Curt mostly because no drilling needed. The Curt installation is very similar to HH, but a couple of holes need to be drilled larger.

Kn.

iewoals

yes, please add more pics of the hitch once installed. I'm considering adding a hitch at some point so the images would be greatly appreciated.

fragil

What a pity that in the States you have always such an ugly tow hitch at your cars. I was a couple of months in Miami and there I saw several beautiful cars with all that same type op tow hitch (square pipe). Here in Europe we can order an original tow hitch from the factory and this is completely unvisible on the car. The socket folds away and the towing bracket itself is kept in the luggage compartment under the floor (see photo).

Spooner

CJ-can you post up a pic of what the Curt looks like? I am going to need to order something pretty quick so I can go riding!

NYCGLK

Do you have pics of that option? Your pic is just a pic of an empty trunk. I have OEM hitch from the factory but it's visible. I had the same reaction to it at first, but now I don't really care.

GLKKa2H

As fragil has yet not replied, I'll attach three pictures, assuming your request still is valid.

You'll see the trunk on fragils picture really is not empty, as the lid of the box storing the hitch is pulled off to show the "uninstalled" hitch (to the right).

slk55er

Is it necessary to order this from the factory at the time the vehicle is ordered so that it is included in the build, or can it be ordered as an added "part" to be installed after the vehicle is completed? If the latter, can we find a way to order that in the USA? Thanks much.

KenNinBC

That system would make mounting up a bike rack pretty difficult.



Kn.

GLKKa2H

Maybe - or maybe not. "Over here" you can buy bike racks which are locked to a tow hitch, from what I've seen in adds. However, being a non-biker have I not paid attention to the make, nor how they are attached/fixed. An issue which from time to time is emphasized, is the requirement for an "light plank" at the back of the bike rack, to ensure the backlights e.g. for brakes etc. are visible.

Happy biking!

allanX204

The European system is different. The bike carrier hooks (is clamped) on to the ball and is not pushed into the tube.

Just to give you a basic idea check these links:
- http://az-carstyling.de/bilder/produ...oss/2111_1.jpg
- http://de.academic.ru/pictures/dewik...r_kupplung.jpg

two movies from Thule's website:
1) http://thule.basilicon.se/#/?guid=19_euro_classic_g5_v2
2) http://thule.basilicon.se/#/?guid=18_bike_euroway_g2_v2

MarkC

I'm under the impression that the OEM system interacts with a special ABS/Stability control algorithms when connected to a trailer. Without this interaction, the vehicle's ABS/Stabilty system would not take into account you are towing a trailer. Front to rear brake bias and anti-sway control features would not match when towing, especially heavy loads like boats and campers etc.

Spooner

I don't know about the other guys, but no way in hell am I going to tow a camper haha. I just have a small utility trailer and a dirt bike so maybe 1,000 lbs max. All the fancy stability electronics is just for people who don't know how to tow...

NYCGLK

i see now thanks. Yea this is a more elegant option. Not sure how much weight that thing can support tho.

GLKKa2H

Our GLK is certified, by the National Traffic Authority, to tow 2000 kg (approx. 4410 lb) with the factory installed tow hitch.

Spooner

Just ordered up the hitch and harness. I will post up some pics when I get it put on.

CJBROWN

Okay, hitch install pics....sorry for the delay, been busy with other projects. I see some fresh posts here that I was not aware of, seems I'm not getting email notices from the site.

The Curt hitch comes in a couple of different model numbers depending on which distribution network you get it from. I got the 13059 from Amazon, it also shows up on Ebay. They are about $200 shipped.

Very nice finish, fairly easy install, I couldn't be happier. Their design has a nice curved main bar and only the center section shows from the back of the car. Some of the others had the hang-brackets exposed and are a bit clunky.

The hardest part was getting the rubber donuts off the muffler hangers, finally ended up using an old jack-handle tire wrench. I removed the stainless exhaust tips so I could pry against the tailpipe. A little WD and they finally came off. Four on the rear and two mid-pipe.

With the exhaust hanging down and out of the way it's easy to get a 1/2" drill and ream out the holes that are already there in the main bumper beams. The second hardest thing was fishing the carriage bolt through the left (drivers side) beam. Curt supplies these really cool fish-wires that screw onto the end of the bolts. I ended up removing it and running it through the beam and then re-attach and finally got it pulled through. The right side is cake because you can fish through the tow-hook port.

Then it's just a matter of raising it up and putting all the bolts and nuts on. Install time was about 2 hours, just like the instructions said.

Looks great and works like a champ!

iewoals

That looks great. Thanks for the update and the pics.

Spooner

I just got mine in on Friday and will probably put it on tomorrow. The exhaust part was worrying me a bit, I hope mine comes off easy!

Spooner

Installed the hitch today. Kind of a PITA but it's a solid product for sure. You were right, the exhaust part was a real pain but once I figured out the right pry bar to use it wasn't too bad. Putting them back on was harder as I was doing it myself. Still need to do the wiring so I might do that tomorrow night.

Spooner

Just did the wiring and it was pretty easy. Hardest thing was just finding the way to get the wiring to the right side. Had to extend the right side wiring a bit too. And yeah, I didn't route the power wire through the lock ring the first time either haha!

With a little luck the weather will hold out this weekend and I can see how she tows the dirt bike to a race.