Hello All,

I am in the market for an awesome family vehicle that tows well. We currently use our '05 CRD Jeep for our towing needs. We have a 19' travel trailer that comes in around 3200. The wheel base is short which can cause for some squirmy towing at times. I know the limit on the GL320 is like 7500 so I am not concerned about the weight, but more about the "feel" of it.

Does anyone else tow a travel trailer/toy hauler with their 320 BlueTech? Should I decide to go this route, a trailer brake will be installed. If you could share your horror stories and successes, that would be greatly appreciated as I look for an upgrade as my family grows.

We do have a large dog, a 1 year old child and talk of #2. So any family success/horror stories would also be greatly appreciated.

Thank you,
Josh

 

havent tried towing, so cant help you there - but we do have a 2 year old and a 3 month old. no issues fitting both car seats in the 2nd row and still have room for an adult to sit in the middle if needed to tend to the kiddos. 3rd row could be folded for dog but my 2 dogs will never see the inside of my 550 - last thing I need is slobber on windows and dog hair matted in the carpet.

 

Now that's just sad.

As for towing, I can tell you from personal experience (of speaking to those who've done it) that the 320 tows like a champ. Put in a brake controller and you can yank all 7000+ pounds without a whimper from the GL. Interior is fantastic for kids - AND dogs! (Big meanie.) And the highway drive is just a dream.

This from someone who's bought what might qualify as a "lemon." I still love the damned beast.

 

I probably would have allowed it (on occasion), until I started reading the Auto care board on this forum and how much damage dog saliva can do to your interior..now I'm paranoid. Besides - would the dogs really be able to tell the difference between riding in the 550 vs my wifes Chrysler 300 company car? lol

 

You can read my experience from about a year ago on this post:

https://mbworld.org/forums/gl-class-...ike-champ.html

As far as sway or squirmy ride, I used a weight distribution/sway control hitch... Rock solid towing 6700 lbs, even with crosswinds.

 

Thank you both for the informative replies and the witty banter. Currently, my '89 Taurus SHO is the dog car of choice, but we do take him on road trips with us. The cloth seats of the CRD will have dog hair stuck in them for the next owner.

Great to know about the towing, I am excited to at least sit in one and perhaps test drive one. So far, all my research has been online. I like the torque of our currently CRD for towing and would like to keep with diesel SUV's if possible. Plus, the fact that you can get 24 MPG HWY with an AWD SUV of this size is pretty impressive.

Thanks again!
Josh

 

Understand that the ESP (electronic stability program) on the truck helps to control trailer sway, too.

 

Well, okay, no, they couldn't. But dog slobber - I mean, that's like saying "my kids will never ride in the thing because boogers eat through the MB-Tex" (which it is my belief they do, if they come out of a kid's nose). It's a badge of honor! Dog snot on the windows! It's to be revered, not feared! Free the snot!

Okay, time for my meds.

 

Right you are Kent. The ESP helps when the sway starts to oscillate worse and worse into an out of control situation.

The sway control that I am using is a friction based device that goes one step further by mechanically controlling the sway...

The ESP combined with the friction based sway control makes for a very stable ride. However, neither one of these cool bits of technology can't make up for improperly loaded or designed trailers... Balancing the load on the trailer is key!

 

I've been towing my race car since day one, and it's a great towing vehicle, with its limitations on towing capacity, but never had any issues climbing, mountain roads, braking, and the mpg is great (last weekend I got 17.4 mpg).
Get a brake controller, the towing package factory installed, and you are good to go.
+1 on balancing the trailer, and proper tire pressure, I've learned from experience how to center my racecars, or atvs, and how much pressure the trailer tires require according to the load and road temperature.
BTW, using the cruise control while towing is a lot better than just pushing on the gas pedal, and downshifting really helps with the braking eventhough the computer senses the trailer and engine brakes by itself, it needs some help.

 

jflem24, you've opened up a can o' worms. The GL320 is a great towing vehicle, but there are a few considerations regarding the 2009 GL320 specifically that I can pass on to you:

-- You need a brake controller. This requires buying a small kit of pins for the brake controller wiring harness (about $15) from the dealer. Also, the rear SAM will need to be replaced ($400) if you didn't buy the factory towing option. Even if you have the factory hitch, you may need to reprogram that SAM, which cost me one hour labor at the dealer, otherwise it won't recognize and properly power the brake controller.

-- You can't mount the brake controller under the dash, because of the new-for-2009 driver's side knee airbag. It can go on top to the left of the console instead.

-- If your trailer has LED lights, it won't be recognized by the computer. You have to fake out the computer in this case. Special cables with resistors built into them are available to solve this problem. UHaul has one for 4-way plugs, eTrailer.com sells a 7-way version. About $35

-- The factory hitch is rated for 7500 lbs, true, but the fine print says only 600 lbs tongue weight. To have proper balance in the trailer (for safety), this effectively limits you to 6000 lbs total towing weight. We broke the factory receiver hitch the first time we used it, in the driveway with a trailer weighing 7300 lbs. I believe that the design of the receiver is entirely inadequate for the stresses of a typical weight distributing hitch. We repaired and reinforced it to take the load. If you tow anything over 3000 lbs I'd recommend taking a long look at the hitch...

-- Keep in mind that you should not exceed Gross Vehicle Weight Rating with the trailer attached, and all passengers/gear in the vehicle. This can be tricky if you have a family and tow a heavy trailer, or even impossible. Look at the numbers before you jump in. If you travel heavy, get a truck.

-- On the 2009 GL320 (Bluetec), you won't have a spare tire. This is a huge consideration when towing. At a minimum, carry a tire plugging kit and a 12v compressor. You don't want to tow on a run-flat that has lost its air. If you get a flat while towing, either reinflate the tire or disconnect the trailer. If this is a deal-breaker, look for a used 2008 or earlier CDI instead, rather than the Bluetec.

Having said all that, I love the GL320 for towing. Tons of power and the 7-speed transmission is perfect. Fuel economy is pretty impressive too. So far I am quite pleased with mine.

More here on my blog

 

Wowzers, thank you! What a huge amount of very good and important information! I do love these forums.

The one thing I would take issue with is "you need a brake controller." If you plan on towing anything of significant weight, you need a brake controller, but even a little bit of weight can be fine with surge brakes on the trailer. I certainly wouldn't use them over, say, 5000lbs (maybe less?), but for small stuff, like most small U-Haul stuff, even loaded up won't need (or even use) a brake controller.

Thank you again for all the really great info - something to think about when someone's buying a GL, whether to go 2009+ or 2007-2008 just because of the new airbag, and for those who don't know about it too!

Great stuff.

STP

 

Great Blog! Looks like you guys are having a lot of fun in that Airstream!

Are you using a weight distribution hitch?

MB had a recall on the 2007 (and I think 2008 as well) hitches on the GL. I took mine in and they re-welded all of the seams just to be safe. I am curious, what did you do to reinforce your hitch... I actually tow more than you and would consider more reinforcement just for safety.

I also stayed within the 600 lb tongue weight... It turns out that in Europe they typically recommend tongue weight be 8% of the trailer weight at minimum... Thus the 600lb tongue weight restriction for a 7500lb trailer weight restriction. With my setup I had around 9% of the trailer weight on the tongue and with the Reese Pro Series SC Weight Distribution / Anti-Sway setup, it is really solid.

 

FWIW, my BMW/Westfalia motorcycle trailer has surge brakes. No brake controller required.

 

Just out of curiosity, what model Airstream do you have? I have a 30' Excella Limited but don't tow it with my MB. I went to your blog but didn't see the camper info.
Thanks

 

We tow with a 2005 Airstream Safari 30 "bunkhouse". It's quite a bit lighter than an Excella 30 Limited, I would guess. As loaded, it weighs about 7300 lbs, which is why I emphasize a brake controller. Certainly for very light loads you can get away with a surge brake, but for any camper over 3000 lbs I'd use a brake controller for superior braking action, and a weight distribution hitch.

Danno4x4, the Reese is a good quality hitch. Normally the recommendation is 10-12% of trailer weight on the tongue, but if you are happy with the handling, that may be the bottom line.

Our hitch was reinforced with gussets and plates to strengthen the connection between receiver box and the main tube. It has performed well for about 3,000 miles of towing so far.

 

What do you do about tow mirrors? It must be nearly impossible to see behind the Airstream with the stock mirrors. Please post if you have found an alternative to stock mirrors.

 

There are good towing mirrors available but I don't personally use them. I agree the standard mirrors on the GL are far too small. Many people swear by the McKesh mirrors sold by Hensley Mfg.

On another subject, I have to sound the alarm again about the 2009 hitch. I just visited a friend who towed his 25 foot Airstream up from Florida with an ML320 (it has the same hitch as the GL320). The factory hitch on his ML320 cracked in the exact same spot as mine, and like mine, it bent left shortly afterward.

If you tow a trailer with your ML or GL, be warned! At the very least I recommend a careful inspection with a flashlight of the entire receiver hitch, especially the two welds which connect the receiver box to the main (round) tube.

 

Josh, attached is a link to a thread I started last year re: our experiences towing with a 2008 GL320CDI. It is consistent with most of what has already been contributed.

https://mbworld.org/forums/gl-class-...iler-long.html

Needless to say we have been more than satisfied with its towing performance. We have covered nearly 7000 miles (mostly Ohio to Sebring & Naples, Fla and back between Jan and March) towing a 24' enclosed Trailex filled with a 3100# VW R32 track car and all the paraphernalia one hauls to the track. We estimate the loaded trailer weights between 5400-5700#s. While towing we average 14-15 mpg which is 50% better than the 2007 Chevy Tahoe it replaced.

And now that ULS diesel is at or below the price of unleaded regular pump gas I look like a genius .

So far the GL320CDI is the best all-round truck or SUV I have ever owned.

 

Be prepared for infamy....

We have been towing a pop-up for a year now with our GL. You would be amazed at the number of people who notice you towing with a Benz, as people always say they have either: seen us on the highway; seen us camping before; heard about us from friends; or remember our trailer from when it was towed by an equally conspicuous Land Rover....

 

I read the thread linked by mxk116. Our experiences are very similar. We're getting 14-15 MPG on diesel, excellent performance, even though our trailer is heavier than his. Our previous tow vehicle got 10.3 MPG most of the time with the same trailer, on gasoline.

It has been recommended to me to try a slightly narrower tire when time comes to replace the stock tires. I'm told this will make the handling on the highway a little crisper and less wallowing, although I'm not unhappy with it the way it is.

"Infamy" has already happened for me. I bought the GL320 because it was the best for our needs, but many people assume I bought it for the nameplate. I get a lot of comments on it.

 

Iridium, Steve - what is a brake controller? I tow about 6,000 lbs - a boat on a double axle trailer with surge disc brakes - and the stop and go can get pretty rough with the surge brakes. Is it possible to convert my trailer to electonic brakes ? Is that what the brake controller does? thx in advance.

 

Electric brakes are not usually used on boat trailers due to being totally submerged while loading and unloading. I think they are water resistant but not waterproof.

 

our towing experience has been wonderful here is link to my experience. Have been towing this boat for 2 years with no problems.

https://mbworld.org/forums/gl-class-...-gl320cdi.html

 

I also posted this question in another thread....

The dealer her is clueless about a brake controller. I took the old service bulletin in and ordered/got the parts to hook a controller up. I have a 09 GL320 with the towing package, so I assume it is ready for the controller.

Will I have to have it reprogrammed after installing a brake controller? Any other considerations?

I also plan to put together a spare tire to carry on longer trips, but don't want to spend the money on an OEM wheel. Any thoughts on aftermarket wheels or sources? Thanks.

Dan, Greenville, SC