2009 Yukon Denali - launching boat sliding tires

[fjlarosa59]

Hello, this is my first post on this forum and I hope somebody can help me with my situation. I have a 2009 Yukon Denali that we purchased so we can tow our 24 foot Baja. Including trailer, gas, and supplies, it ways about 6,500 pounds. This vehicle is rated at 8,100. It has the 6 liter, 403 HP, and has AWD along w/ the trailering package. However, I recently launched my boat for the first time, second time, and third time, and much to my surprise, the darn front tires started sliding. It's as if the boat is pulling the vehicle down the ramp, which is probably what's happening. In one case, the ramp was a little wet and in another it wasn't. I used trailering mode, turned off the traction control, called my dealer and nobody knows why it's doing this. The tires are in great shape also.

Has anybody experienced this and if so, what did you do to solve this problem?

Thanks, Frank

 

[Zed 71]

How steep is the ramp? What is the tongue weight with the boat on? The combination of the tongue weight and ramp angle may shift the weight bias to the rear causing the fronts to lose traction.

Also, what kind of tires do you have? I am assuming the truck has AWD (vs 4WD) since it is a Denali.

 

[baron]

Is it pulling it down when you have your foot on the brake? Also, since I haven't backed a boat into the water with mine yet, why are you turning off the traction control? I have seen many a "big, bad" truck slip on a boat ramp because the grade is steep, their is gravel, sand, water, etc.

 

[stevek]

The car is on an incline and it's a lot of resistance to get the boat trailer through and out of the water. Since the center of gravity of the car is towards the rear on an angle like that AND the fact there is a trailer shifting the COG even further back, the front tires are inclined to spin a little bit while the rear tires do all the work

 

[SabrToothSqrl]

leave the traction control on... long as your not spinning the tires around your fine... just give it less gas, gentle! I have a Chris Craft 245 LTD w/a 460 in it...

 

[baron]

Ah, I missed where he said it was just the front tires and I only saw the word sliding... I was imagining his whole ride sliding back on the ramp while holding the brakes, which, like I said, I have seen a number of well equipped trucks do that. If the front wheels are just spinning a bit, that is pretty normal, just like stevek said, you are going to have a lot of rear weight bias. Nothing I would worry about.

 

[fjlarosa59]

Thanks for the replies everybody. I do realize the traction control being off doesn't work, but I was just trying it for the heck of it. I also recognize the center of gravity shifts to based on the weight of the boat. The tires are stock (I don't have the vehicle home and I can't remember) and it is AWD. Yes, it's sliding when I have the front brakes on. BTW, the vehicle does pull the boat out ok, although there has been a little slippage by the front tires. I'm just worried about being pulled into the water and was hoping there was a solution to this out there somewhere. Everybody I talk with about this hasn't seen this before.

 

[stevek]

Thanks for the replies everybody. I do realize the traction control being off doesn't work, but I was just trying it for the heck of it. I also recognize the center of gravity shifts to based on the weight of the boat. The tires are stock (I don't have the vehicle home and I can't remember) and it is AWD. Yes, it's sliding when I have the front brakes on. BTW, the vehicle does pull the boat out ok, although there has been a little slippage by the front tires. I'm just worried about being pulled into the water and was hoping there was a solution to this out there somewhere. Everybody I talk with about this hasn't seen this before.

Wait, it's sliding DOWN the ramp with the brakes on? Are you pulling/launching the boat in park with the E-brake on?

Make sure your tires aren't over-inflated... have them around 30 (the pressure doesn't give me any problems)

 

[BlizzardX23]

I cant help either....


I just launched our boat yesterday in my 03 Denali...with no slipping, on a wet dock..




please explain your launching process from start to finish, with detail... (how many people are helping, whos driving truck, whos on boat doing what...) maybe we can see whats causing this...

 

[fjlarosa59]

Definitely no ebrake on. I thought about the tire pressure also and will reduce it to see if that makes a difference. Can't hurt at this point.

As far the process, simply backing the vehicle and boat down the ramp in reverse, moving very slowly, pacing down the ramp (this is when it starts to slide), until I eventually get it in the water. The boat has people on it, maybe 3 or 4 and only one person in the vehicle.

What about the ball. I have a drop down ball that levels the boat and the vehicle. Would that make a difference if I put a lower drop down on it?