Humorous Story and Question

[Joseph Garcia]

Hi Folks,

I thought that I'd share a humorous story with you, and then ask for your thoughts and perspectives on a question that came out of this story.

Story:

I get a call from, my oldest son asking if my Yukon is available to assist him with a problem. I say sure and ask him what the problem is. He tells me that he's trying to cut down a large maple tree in his yard that is too close to his house. So, in order to ensure that the tree does not fall in the direction of his house, he was going to use his pickup truck as an anchor, and attach ropes from the truck to the tree, prior to taking the chain saw to the tree.

He is in the process of re-leveling and re-landscaping his back yard area for better drainage, and the area was all torn up as part of the re-leveling project. So, it was not going to be an issue driving the truck over that area, to get it in the proper position to serve as an anchor. Or, was it.....




So, I get my tow strap and head over to his house to help him get his truck out of the mud. On the way over, I text my youngest son to tell him what I am doing, and he texts back, "ROFL!! Sending a GM luxury SUV over to pull a fully feature loaded Ford F250 pickup truck out of the mud! Priceless!!"

Anyway, we did get his truck out of the mud, and my oldest son is quite humbled by the experience.


Question:

In our first attempt to rescue my son's truck, we simply put the tow strap on the receiver balls of both trucks, my son puts his truck in 2 wheel (rear) drive and in reverse, and we try to pull the truck out of the mud. His truck's rear tires start to spin, and my truck's rear tires start to spin and dig into the mud, and we realize that this is not going to work.

So for, our second attempt, we dig out the mud from behind his front tires and place long wood planks under the back edge on the front tires, my son puts his truck in 4 wheel drive and in reverse, and we successfully pull his truck out of the mud.

My question here is that on our first and failed attempt, my Yukon's rear tires started to spin and dig into the mud, but there was no evidence of any spinning of my Yukon's front tires. I would have though that with AWD, I would have seen evidence of spinning of all 4 tires. On that attempt, I started with the transmission in manual 1st gear, but then I later switched the transmission to automatic 'D' position. In neither case, did I see any evidence of the front tires spinning.

Is this normal or expected behavior of the Yukon's AWD in this scenario? Is there something that I should have done to force power to all 4 tires in this scenario?

Your thoughts and perspectives are most welcome.

 

[Doubeleive]

the power split is not 50/50, not sure what it is exactly I think it is 60/40 or something of that nature, Could have been traction control taking over if you did not have that disabled. Traction control and driving in mud do not mix well, if you put it up on 4 jack stands and put it in drive all 4 wheels should spin.
I am sure some one else with more knowledge will chime in.

 

[gooffeyguy]

The torque split is 60/40 on the awd transfer case. I think your problem had to do with traction control and Stabilitrak still on

Sent from my SM-G930V using Tapatalk

 

[kbuskill]

Not 100% sure about these trucks but the older trucks used a viscous coupling inside the AWD transfer case and the rear tires would have to spin up to a certain speed/rpm before the viscous coupling would really transfer power to the front wheels. I have heard of guys partially setting the parking brake to put some resistance on the rear wheels in order to transfer power to the front wheels. I seriously doubt this is good for the transfer case or the brakes for that matter.

I know that on the regular 4wd trucks, of this Gen, that in order to get full power to the wheels the ABS has to be disabled by pulling the ABS fuse (#9 if memory serves). If not the Stabilitrac and Traction control will over ride things. Turning the ST and TC off with the buttons doesn't cut it. There are videos on the tube that show this fuse method in action.

 

[avalonandl]

Your first issue is you need extra weight. A 24 pack of Budweiiser

 

[Rocket Man]

Your first issue is you need extra weight. A 24 pack of Budweiiser

Or 2 fat chicks sitting in the third row AND a 24 pack of Budweiser in your gut which makes the fat chicks look hot.

 

[CaptainAmerica1]

Nvm…

 

[adventurenali92]

Not 100% sure about these trucks but the older trucks used a viscous coupling inside the AWD transfer case and the rear tires would have to spin up to a certain speed/rpm before the viscous coupling would really transfer power to the front wheels. I have heard of guys partially setting the parking brake to put some resistance on the rear wheels in order to transfer power to the front wheels. I seriously doubt this is good for the transfer case or the brakes for that matter.

I know that on the regular 4wd trucks, of this Gen, that in order to get full power to the wheels the ABS has to be disabled by pulling the ABS fuse (#9 if memory serves). If not the Stabilitrac and Traction control will over ride things. Turning the ST and TC off with the buttons doesn't cut it. There are videos on the tube that show this fuse method in action.

This is only partially true. The actual pick up trucks in the GMT800 platform that were AWD had a viscous couple in the transfer case, however the AWD SUV variants did not have the viscous coupler transfer case, it’s a different set up.

 

[Rocket Man]

This is only partially true. The actual pick up trucks in the GMT800 platform that were AWD had a viscous couple in the transfer case, however the AWD SUV variants did not have the viscous coupler transfer case, it’s a different set up.

That depends. My NVG149 TC has a viscous coupler.

 

[adventurenali92]

That depends. My NVG149 TC has a viscous coupler.

Well that’s because you have a 2002 lol I think it changed in 2003.