Thread: Traction Control on 11MY Defenders

There has been some discussion over the last couple of days on the Pommy Defender Forum (Defender2) concerning traction control (TC). I thought AULRO Defender people would be interested. What was particularly interesting was posted by James from Taunton who obviously works for Land Rover. James was saying that in pre11MY Defs TC works across each axle, while in post 11MY Defs it works on all 4 wheels. His explanation follows:

"So i will attempt to explain using my job, this one and last one for 6 years, plus pre production work we completed on 11MY TC systems.

TC will work on all 4 wheels. what i am saying is that it only senses across axles on pre 11MY. so:

CDL unlocked;

front axle left is spinning, TC will brake the front left to divert power to the front Right. regardless of what the rear is doing. the rear axle wheels could be stationary and no TC working. all the power is taking the easy route through the mid diff to the front diff. TC is then splitting that power at the front diff. (power being used as a generic term)

or the rears could say have right hand wheel also spinning, in which case TC will brake rear right and divert power to rear left. TC is working and it is working on all four wheels but it is not sensing the speed differences between front and rear axle wheels.

to continue this same example, therefore, if the front TC interacted and ended up with both front wheels doing say 5mph, the rear could of interacted and ended up with the rears wheels both doing 10mph. there is nothing to (pre 11MY) to make them all do the same speed from a TC perspective. (TC aims to have the wheels turning at the same speed within tolerances, the system obviously allows for turning corners, hence the delay at slow speeds when you loose traction before TC cuts in, you need to exceed the expected turning speed of one wheel for it to be going around a corner at a set engine speed)

The reason the original system was across axle only was the CDL, this should be engaged prior to conditions where you feel you may loose traction. you then get power 50% power front and rear. the TC is still working across each axle, but these are now joined by the CDL will mean all 4 wheels will have TC interaction as required to turn them all at the same speed.

On your loose gravel tracks or wet tarmac you can still get TC working. see the first para example. Go into a corner, loose traction on a front wheel as you apply power and TC will cut in. There is no CDL locked then.

on 11MY defenders the TC senses speed across all 4 wheel stations, such as D2, T5 platform and LR2s. It is therefore more efficient as it does not need the CDL to be locked as it can mimic this, granted from a reactive point of view. Use of the CDL is a preventative measure."

Cheers
KarlB

I agree with Rick and BigJon - you're only supposed to drive at a max 60 km'h with the CDL in anyway. I only use mine if I'm going to lift a wheel or likely actively need TC.