Octavia Scout 2008 - Which Haldex

[nidgep]

hi

 

I'm sure that this question must have been asked a dozen times already, but having searched the forums I didnt find a definite answer.

 

I have just bought a 2008 Octavia Scout 2.0 PD (BMM).

 

Can anyone advise, how I can reliably find which Haldex version the car has?

 

I have already noted on this site that there seems to be a bit of ambiguity as to whether is its reactive Haldex 2 or preemptive Haldex 4.

 

cheers

 

 

[drmike]

Pre facelift = gen 2

Post facelift = gen 4

[nidgep]

Thanks for the reply drmike.

 

Short n sweet :-)

 

For some reason I had hoped that my car had Haldex 4 - simply from the point of view that prevention must be better than cure (wheel spin)?

Is the main difference between Haldex 2 and 4 the fact that haldex 4 is anticpating loss of grip rather than reacting to it?

[philbes]

If it is anticipating loss of grip how does it do that?  What parameters are being measuring?

[Nomads]

My (limited) understanding is that Gen 2 isn't a pre-tensioned device but relies on a pump that activates once slippage occurs. Gen 4 is pre-tensioned meaning it reacts AS the wheel slips, not ONCE is occurs.

[nidgep]

My understanding is the same.

For Haldex IV,

• the throttle position,
• engine torque and
• road speed

are used in the decision making process as to when the clutch is pretensioned.

The pretensioning is electronically controlled, activating all wheel drive before the wheel slips.

[trundlenut]

Unless you provoke a significant amount of under steer I have found the gen2 hakdex to be pretty good and progressive. I have a couple of tightish bends I regularly travel round and you can feel the haldex working but smoothly.

Chuck it into a tight bend too quickly and you can feel the power kick in at the rear with a snap which can be a bit disconcerting.

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[London Les]

There is quite a good explanation if you google Haldex 4 @ http://www.awdwiki.com/en/proactive/

 

The system is still somewhat crippled by the back open diff IMO.

[trundlenut]

There is quite a good explanation if you google Haldex 4 @ http://www.awdwiki.com/en/proactive/

The system is still somewhat crippled by the back open diff IMO.

It's great in the winter though. Turn off the traction control and you can displace a significant amount of snow

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[DGW]

If it is anticipating loss of grip how does it do that?  What parameters are being measuring?

The answer may be in the Tiguan Haldex (Gen 4) All-Wheel Drive Self Study Program downloadable via the link below. It certainly makes interesting reading.

http://www.freel2.com/gallery/albums/userpics/11383/tiguan_haldex_gen4.pdf