D2 traction control VS CDL being locked

[Fivespddisco]

There's always a lot of questions when you talk about the center diff lock. Especially on the discovery 2. To make matters worse there is a lot of crazy information on the web. I hope this quick video will help clear up some of the confusion and miss-information. Enjoy.

http://www.youtube.com/watch?v=yAuxGyU3uSQ&list=UUUnCLXtAqip_9qd-T1NenbA&index=2

 

[Ronct110]

Thanks for posting.

My wife and I are planning a trip to our local vehicle recreation area in Hollister, CA; she wants more practise and will be driving our D2, and I will be in a Range Rover Classic on the obstacle course in Hollister. I was explaining to her CDL and traction control on our DII, and your video helped w/the visuals; thanks!

 

[LR Max]

Was that CDL and TC working together? I think that is the best setup overall, both working together.

 

[BirchHill]

It appears he is having a problem with his traction control. There was no indication whatsoever that it is functioning. Even if it cant climb the obstacle you still will see the power shift around to the other wheels. When the braking system is in working order it would have no problem clamping down on the one wheel spinning and you would see this in the power hopping around to some of the other wheels.

 

[Fivespddisco]

It appears he is having a problem with his traction control.

It was working fine.

There was no indication whatsoever that it is functioning.

At about 1:45 you can see the tires spinning faster and slower as the brakes engage.

Even if it cant climb the obstacle you still will see the power shift around to the other wheels.

That's why I stopped and took the time to film at that particular obstacle. It was the perfect set up. The Disco had great traction on all three tires but due the one tire off the ground it could not overcome the incline. With all the traction available for the other three tires this made the front brakes the weakest point in the traction link. Another way to put it is. It was easier for the motor to spin the front tire with the brakes on than it was to push the 5000 pound truck up the hill.

 

[BirchHill]

This doesnt jive with what my experience has been with the traction control, I have found it effective in situations with lifted tires and cross axle like in ledge climbs but it seems to struggle in loose hill climbs or mud where there really is no tire with a better grip then the others. But, as they say your results may vary.

 

[ExploringNH]

My experience has been exactly what happened in the video. The traction control pulses the brakes and in situations like this one never applies enough pressure for long enough to get the truck up and over. If it were to lock the spinning tire with enough force to effectively transfer power to the tires with traction, then it would be no problem. Unfortunately, the force it takes to get the rear tires, especially the one with the most traction, spinning is greater than the force that the traction controlled brakes are able to apply. With a little momentum, this can be overcome but that is not always possible or wise.

Mine is an 04, for what it is worth.

 

[BirchHill]

Tc is only as good as your brake system. Cheap pads and poorly lubed caliper slides gets you the kind of performance shown in the video.

Here is a video of a properly working tc system vs a cdl equiped jeep. https://www.youtube.com/watch?v=jLBg4-dI05A

 

[bmxer06pa]

Tc is only as good as your brake system. Cheap pads and poorly lubed caliper slides gets you the kind of performance shown in the video.

Here is a video of a properly working tc system vs a cdl equiped jeep. https://www.youtube.com/watch?v=jLBg4-dI05A

That video you keep posting of that tiny hill next to a road doesn't prove anything. If you have ever filmed off road you would know that the video never truly shows the steepness of a hill or the size of an obstacle. The difference a locked cdl makes over just traction control is night and day. There is a reason so many off road vehicle come with a lockable transfer case from the factory. Perhaps you should put one in your truck and then you can experience it for yourself.

 

[Fivespddisco]

Tc is only as good as your brake system. Cheap pads and poorly lubed caliper slides gets you the kind of performance shown in the video.

There was nothing wrong with the braking system on the truck in our video. The truck had been off-road for three consecutive days but I wouldn't consider this a problem with the braking system.

When the braking system is in working order it would have no problem clamping down on the one wheel spinning and you would see this in the power hopping around to some of the other wheels.

Like I stated earlier the engine has more power to spin a tire then the brakes do to stop it.
If you don't believe me. Put your truck in low put your foot on the break and step on the gas at the same time. I'm guaranteeing you the truck will drive away with your foot on the brakes and you will be using all 4 pads.

In your video look at 1:20 to 1:27. The disco does not move forward until the tire comes back down and touches the ground.

On a sidenote this isn't really a fair comparison between the two trucks. The disco has a longer wheelbase then the jeep. This gives the Disco the advantage for this particular obstacle. You'll notice the rear tires stay almost on the pavement until the front tire has already cleared the upper obstacle.

 

[BirchHill]

That video you keep posting of that tiny hill next to a road doesn't prove anything. If you have ever filmed off road you would know that the video never truly shows the steepness of a hill or the size of an obstacle. The difference a locked cdl makes over just traction control is night and day. There is a reason so many off road vehicle come with a lockable transfer case from the factory. Perhaps you should put one in your truck and then you can experience it for yourself.

As you said the video of the small hill by the road does not show well in the video. I have cdl equipped vehicles so i am aware of the comparisons. I also know the tc works better then shown.

 

[BirchHill]

There was nothing wrong with the braking system on the truck in our video. The truck had been off-road for three consecutive days but I wouldn't consider this a problem with the braking system.




Like I stated earlier the engine has more power to spin a tire then the brakes do to stop it.
If you don't believe me. Put your truck in low put your foot on the break and step on the gas at the same time. I'm guaranteeing you the truck will drive away with your foot on the brakes and you will be using all 4 pads.

In your video look at 1:20 to 1:27. The disco does not move forward until the tire comes back down and touches the ground.

On a sidenote this isn't really a fair comparison between the two trucks. The disco has a longer wheelbase then the jeep. This gives the Disco the advantage for this particular obstacle. You'll notice the rear tires stay almost on the pavement until the front tire has already cleared the upper obstacle.

That is not an accurate description with standing on brakes and flooring. The traction control just has to brake until the resistance on the spinning tire is greater then the resistance of the tires with traction. It is well with in the capabilities of the braking system when function properly to do this. That is in no way similar to braking a full throttle truck in low gear.

 

[Fivespddisco]

That is in no way similar to braking a full throttle truck in low gear.

Eli's truck was in Low so it is the same.

The traction control just has to brake until the resistance on the spinning tire is greater then the resistance of the tires with traction. It is well with in the capabilities of the braking system when function properly to do this.

Okay I understand your point but try this test.

Take your truck on a very steep incline and see how much throttle it takes to drive up.

Now use that same amount of throttle with your foot on the brakes the truck will still move.

The end result is your asking one brake to transfer enough horsepower to move a 5000lb truck up a steep incline. It cant do it, Im sorry

 

[BirchHill]

Your missing a key point, the goal of the tc is limited slip, it is not to stop the wheel cold dead. Your description with holding the brakes and hitting the throttle does not take this into account. The goal is not to stop the wheel but, to increase the resistance enough on the spinning wheel to overcome the resistance of the non moving wheels with traction. If the traction control was locking up wheels that would be useless, fighting against itself and any forward motion would cease to exist. Im not saying tc is some super thing, its messy, noisy tears up the ground and is disabled by the 3 amigos or a damaged wire way too easy, but i have seen it perform much better then your video showed. Will i put a cdl on mine? probably going to have to drop the t case down to replace input seal so i might as well why its out on the bench.

 

[ZG]

Birchhill, I'm not going to lie, the DII's TC system is kind of a joke. It's nothing like the LR3/LR4. There's a reason I just spent gobs of money to put a new T-case and ashcroft CDL in my Disco, the CDL is incredibly important.

On a side note to Justin, on LRForums someone mentioned that their mechanic said using TC and CDL would blow their t-case up. I have never heard such a thing, have you witnessed this?