GL450 Pulling a Boat
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Joined: Jun 2007
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2007 GL450
GL450 Pulling a Boat
Trailered a 25 foot pontoon boat about 80 miles today to bring it to the dealer for winterization and some servicing. The weight of the trailer, boat, engine, gas and stuff in the boat was about 4,200 pounds.
The suspension is really neat. When you hook up the trailer it pushes the rear end of the truck down. The when you start the engine the rear suspension pumps up and levels out the truck perfectly. Very cool!
Taking off from a stop, even up grades there is plenty of power.
Most of the driving route was highway at 65 mph.
The truck pulled the load very well. I was using cruise control and I could tell that there was a lot more downshifting as the truck maintained speed while going up hills. But it maintained speed fine.
Just a little sway, I wouldn't considered it bad. That big boat catches a lot of wind. It was a nice day, not too windy, but I had to concentrate on driving especially when I big 18 wheeler would pass.
I could not help but wonder how things would be different with the GL320 CDI? I wondered if there would be less downshifting to maintain speed going up hills while at 65 mph? I wondered if the take off from stops would feel noticably more powerful, because the GL450 seemed to do fine?
Anyway, it was a good experience pulling 4,200 pounds today.
Gordon
The suspension is really neat. When you hook up the trailer it pushes the rear end of the truck down. The when you start the engine the rear suspension pumps up and levels out the truck perfectly. Very cool!
Taking off from a stop, even up grades there is plenty of power.
Most of the driving route was highway at 65 mph.
The truck pulled the load very well. I was using cruise control and I could tell that there was a lot more downshifting as the truck maintained speed while going up hills. But it maintained speed fine.
Just a little sway, I wouldn't considered it bad. That big boat catches a lot of wind. It was a nice day, not too windy, but I had to concentrate on driving especially when I big 18 wheeler would pass.
I could not help but wonder how things would be different with the GL320 CDI? I wondered if there would be less downshifting to maintain speed going up hills while at 65 mph? I wondered if the take off from stops would feel noticably more powerful, because the GL450 seemed to do fine?
Anyway, it was a good experience pulling 4,200 pounds today.
Gordon
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Joined: Apr 2006
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From: Florida, USA
2017 Rolls Royce Wraith, 1999 CLK Cabriolet, 2023 Genesis G90
That's impressive. Does your trailer have electric brakes or those that are actuated by mechanical means? If they're electric, did you install the electronic brake controller on your GL? Inquiring minds want to know.
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From: Spicewood, TX
2008 GL 320, 2007 Silverado LTZ C3500 Duramax Turbo Diesel
That is impressive looking, Although pontoons don't weigh a lot, they are like dragging a parachute. I assume it has surge brakes since electric brakes don't go well with water. I can't tell you how well the GL 320 will do. Even though it has a trailer hitch, the C3500 Duramax will see all the towing duties.
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From: LA LA Land
'07 GL 450, '02 S 80 T6
Originally Posted by Nevada Jack
That second shot is awesome! The boat makes the GL look like a toy but a powerful one...:-)
Glad to hear of your nice experience, Gordon. Did you get a factory hitch or you had one installed aftermarket?
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2007 GL450
oknish,
I had a factory hitch.
The only thing I had to search for was a longer ball mount.
On my Montero Sport the factory hitch sticks out from the bumper by 4 inches and is high off the ground. On the GL450 the factory hitch is deep to the bumper by 4 inches and is low to the ground.
Standand ball mounts that I could find measure 6 inches from the center of the pin hole to the center of the ball hole. If you use one of these the ball mounts on the GL the ball becomes VERY close to the GL bodywork and doesn't leave a lot of room for mistakes when you are backing up to hook up the trailer!
I went to a local RV Center and they had a longer ball mount. It measures 11inches from the center of the pin hole to the center of the ball hole. Then because the GL hitch is so low to the ground you mount the ball with the curve of the ball mount going upwards. Worked well.
Gordon
I had a factory hitch.
The only thing I had to search for was a longer ball mount.
On my Montero Sport the factory hitch sticks out from the bumper by 4 inches and is high off the ground. On the GL450 the factory hitch is deep to the bumper by 4 inches and is low to the ground.
Standand ball mounts that I could find measure 6 inches from the center of the pin hole to the center of the ball hole. If you use one of these the ball mounts on the GL the ball becomes VERY close to the GL bodywork and doesn't leave a lot of room for mistakes when you are backing up to hook up the trailer!
I went to a local RV Center and they had a longer ball mount. It measures 11inches from the center of the pin hole to the center of the ball hole. Then because the GL hitch is so low to the ground you mount the ball with the curve of the ball mount going upwards. Worked well.
Gordon
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Joined: Feb 2007
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From: LA LA Land
'07 GL 450, '02 S 80 T6
Originally Posted by gordongl450
I had a factory hitch.
The only thing I had to search for was a longer ball mount.
On my Montero Sport the factory hitch sticks out from the bumper by 4 inches and is high off the ground. On the GL450 the factory hitch is deep to the bumper by 4 inches and is low to the ground.
Standand ball mounts that I could find measure 6 inches from the center of the pin hole to the center of the ball hole. If you use one of these the ball mounts on the GL the ball becomes VERY close to the GL bodywork and doesn't leave a lot of room for mistakes when you are backing up to hook up the trailer!
I went to a local RV Center and they had a longer ball mount. It measures 11inches from the center of the pin hole to the center of the ball hole. Then because the GL hitch is so low to the ground you mount the ball with the curve of the ball mount going upwards. Worked well.
Gordon
The only thing I had to search for was a longer ball mount.
On my Montero Sport the factory hitch sticks out from the bumper by 4 inches and is high off the ground. On the GL450 the factory hitch is deep to the bumper by 4 inches and is low to the ground.
Standand ball mounts that I could find measure 6 inches from the center of the pin hole to the center of the ball hole. If you use one of these the ball mounts on the GL the ball becomes VERY close to the GL bodywork and doesn't leave a lot of room for mistakes when you are backing up to hook up the trailer!
I went to a local RV Center and they had a longer ball mount. It measures 11inches from the center of the pin hole to the center of the ball hole. Then because the GL hitch is so low to the ground you mount the ball with the curve of the ball mount going upwards. Worked well.
Gordon
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2007 GL450
RaechWest,
Yes, it is a long load and you have to make wide turns.
The GL450 was impressive pulling the boat. It was really smooth. I have to pick the boat up this weekend and bring it home, so I will do the same trip in reverse. I am hoping for clear weather again. We'll see how the return pull goes.
Gordon
Yes, it is a long load and you have to make wide turns.
The GL450 was impressive pulling the boat. It was really smooth. I have to pick the boat up this weekend and bring it home, so I will do the same trip in reverse. I am hoping for clear weather again. We'll see how the return pull goes.
Gordon
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2007 GL450
Hill Assist Works Great!
One thing that I forgot to mention is Hill Assist. It is amazing. I have to pull the pontoon out of the water on a long concrete boat ramp that has quite a pitch to it. Not only the part of the ramp that goes into the water, even after you get out of the water the ramp is still going up hill.
Well, Hill Assist will hold the entire load for you after you put the truck in Drive and then come off the brake and give it gas. There is NO rolling backwards. It's great! My wife loved it because she is the one who is pulling the boat out of the water, because I am in the boat at that point. Rolling backwards on the boat ramp would make her nervous when we used to pull boats out of the water with my Montero.
Gordon
Well, Hill Assist will hold the entire load for you after you put the truck in Drive and then come off the brake and give it gas. There is NO rolling backwards. It's great! My wife loved it because she is the one who is pulling the boat out of the water, because I am in the boat at that point. Rolling backwards on the boat ramp would make her nervous when we used to pull boats out of the water with my Montero.
Gordon
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E320 & GL450
Does any one know what comes with the new GL's with installed factory hitch regards installing a trailer electric brake controller. I was at my MB dealer yesterday and they assured me MB now furnishes a 4 wire pigtail (like all US made tow vehicles) with a connector interface to GL vehicle electronics that can be used to integrate a controller. MY GL is due the second week in November and we still have some tailgates left. My Valley Odyssey controller is on order and has a kit with the four wires ready to go.
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From: Scottsdale, AZ
2004 RX330, 2008 Scion xB, 2001 Honda Insight Hybrid, 2010 Toyot Prius v ATP
I've got something like that for my Excursion, but there's no cable between the two plugs - it's just one plug right into the other.
STP
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E320 & GL450
Thanks. Need the 7 pin for electric trailer brakes. I read so much on this and other forums about the issues that customers had with the early 2006/2007 GLs where MB did not even run the 4 wires you need for electric brakes (gnd, power, brake light circuit and variable voltage from controller) back to the 7 pin receptacle. Apparently they fixed this in December 2006 in profuction. They then issued a TB in March of 2007 covering the issue. My question is trying to verify the statements by my dealer parts folks that MB now issues a pigtail (a connector with 4 wires) that plugs into the receptacle near the fuse box and will allow you to connect the 4 wires to your contrller. Not imperatvie to verify, but it would be nice to know.
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2007 GL450
tm4exec,
Glad to help. That is the extent of my knowledge on the hook ups. I don't know anything about how to use all the pins or anything about electroninc brake controllers.
Good luck. The truck pulls great.
Gordon
Glad to help. That is the extent of my knowledge on the hook ups. I don't know anything about how to use all the pins or anything about electroninc brake controllers.
Good luck. The truck pulls great.
Gordon
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GL450
did you ever get the pigtail?
Thanks. Need the 7 pin for electric trailer brakes. I read so much on this and other forums about the issues that customers had with the early 2006/2007 GLs where MB did not even run the 4 wires you need for electric brakes (gnd, power, brake light circuit and variable voltage from controller) back to the 7 pin receptacle. Apparently they fixed this in December 2006 in profuction. They then issued a TB in March of 2007 covering the issue. My question is trying to verify the statements by my dealer parts folks that MB now issues a pigtail (a connector with 4 wires) that plugs into the receptacle near the fuse box and will allow you to connect the 4 wires to your contrller. Not imperatvie to verify, but it would be nice to know.
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2011 GL350 Bluetec, Irridium over Black Leather
Was just wondering if you ever got the pigtail or did you just figure another way around the issue? I am in the same boat I want to add a electric brake controller but not sure if I need it with the factory 7 pin tow hitch plug. Do you still need a controller to work the brakes on a trailer?
Surge brakes (ie typical boat trailer) - no brake controller required.
Electric brakes (ie typical flatbed or enclosed trailer) - brake controller required.
I like this one:
http://www.tekonsha.com/content/prod...435&part=90250
Mounts to the trailer, not the tow vehicle.
- Mark
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Joined: Sep 2008
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From: Charlotte, NC
'07 GL450, '98 Wrangler
Great looking pic of the GL pulling your boat. I agree with your assessment: pulled our 21" SeaRay many times and never had a problem. But certainly can't beat Scotty's C3500 Duramax Power Diesel - you could probably pull a 35" with that thing ;-)
