When did you last need your diff lock?

[soulstyledevon]

Or an old favourite...

Anyone ordering 4motion needs to watch this.
Because, I’m sure it would convince most that the diff-lock is worth having...

 

[Loz]

This is me using the diff lock on our Touareg to carefully negotiate the mountain tracks on Corsica.

 

[B J G]

Unless intending to use in situations suited more to a purpose designed 4x4 vehicle a combination of skilled driving and the 4 Motion will cover the vast majority of situations. After all the majority of Cali owners manage OK with 2WD.

There is also the risk that over use or misuse of the Diff lock can cause mechanical failure of the Diff or drivetrain component.

Basically not a must have but down to personal cost justification.

 

[Kernowboy]

There is also the risk that over use or misuse of the Diff lock can cause mechanical failure of the Diff or drivetrain component.

Or underuse presumably. Loads of posts on diff lock saying nice to have but never used it, not many at all saying it‘s been needed in normal Cali use.

 

[B J G]

I don't have it and not needed it or even nearly needed it.
It could be argued that common sense wouldn't put a Cali into an area that getting bogged down was probably going to be the outcome.

 

[Calimili]

I am not an off-road expert, but it seems clear that a diff lock is needed when a wheel has completely no traction spinning off the ground. It has to be quite a dramatically uneven terrain where a front wheel lifts up and you could only proceed, if you could not carry any momentum, by engaging the diff. lock.
Before I would venture in such terrain, I would personally upgrade suspensions and tyres before thinking about diff lock.

 

[GrannyJen]

I don't have it and not needed it or even nearly needed it.
It could be argued that common sense wouldn't put a Cali into an area that getting bogged down was probably going to be the outcome.

For some people putting a Cali into that situation, and getting out again, is the objective

I picked Albert up in the January (2014), quite desperate to find some snow somewhere to play with the 4motion. Albert did not have a diff-lock. Alfie does. Never had to use it but then my lifestyle has changed.

There are some superb video's on here, @bvddobb being just one owner, who have taken there Cali's to some incredible places. They make great watching, if that's your sort of thing!

 

[Kernowboy]

Also no expert but trying to gain a better understanding before too late to add to my order If justified. From what I can work out it would actually only be needed if a wheel on each axle loses traction, so 2 in the air or otherwise compromised for grip. If just front wheel then drive would transfer to rear, if a rear wheel also lost grip then you’d need to then lock rear diff to go anywhere. Am I on the right track, or missing something?

 

[WelshGas]

I would work on the premise that if you have to ask the question " Do I need a Diff Lock?" then the answer is No.
If you are experienced in off-road driving then you'll know.
Do a 4 wheel drive off road course and you'll see what's needed. Tyres, suspension and ground clearance first.
I used to have a Defender and took it to places I wouldn't contemplate taking my California to without significant modification and a diff lock would have been the last modification.

 

[bvddobb]

It has to be quite a dramatically uneven terrain where a front wheel lifts up and you could only proceed, if you could not carry any momentum, by engaging the diff. lock.

Not completely correct...

If traction is lost/low on one axle, the system transfers traction to the other axle. So, in your example, if one front wheel is off the ground, traction is transferred to the rear axle, and that will enable you to still drive.

Only if traction is lost on both axles (e.g. one rear wheel off the ground, one front wheel off the ground) the Haldex system has an issue potentially, but then the 'electronic diff lock' kicks in, braking the spinning wheels through ABS, so that traction is transferred to the wheels still on the ground.

Believe me, we've been there several times! See e.g. some of the videos we posted on this forum from the Seikel 4M off-road trainings, you will see several examples of 'wheels off the ground' while the van still rolls along happily... We have been there in most of our travels as well.

 

[Tarquers]

Also no expert but trying to gain a better understanding before too late to add to my order If justified. From what I can work out it would actually only be needed if a wheel on each axle loses traction, so 2 in the air or otherwise compromised for grip. If just front wheel then drive would transfer to rear, if a rear wheel also lost grip then you’d need to then lock rear diff to go anywhere. Am I on the right track, or missing something?

Afraid that is not the case, because there is no centre diff lock so any wheel spinning takes all the power so on its own (without EDC) it is no better that 2WD apart from in on road situations. (ready for the flood of abuse here!). One wheel in the air, or even on wet grass, is enough to put the 4motion to make it necessary to use excessive speed to get out of a sticky situation.

4motion is designed for on road scenarios, so in the instance where there is a loss of traction on the front wheels causes spin, power is sent to the rear through the haldex clutch and reduces spin. Same scenario in towing where the front wheels are light, more power goes automatically to the rear to aid traction.

When you get into a scenario when one wheel lifts, the system will try to use the brakes to stop power being lost through the spinning wheel (6:23 in the video in post 24). You will get a lot of wheel spin before the system kicks in, and it will start and stop again each time you change throttle position.

The advantage of the diff lock is that it firstly splits power between the front wheels and the rear wheels 50/50 whilst locking the rear axle together ensuring that the rear wheels will turn together (you may see slight spin after engagement). This allows a much slower speed to be used and maintained which is important to prevent damage to a vehicle not designed for full off road, and in the most part, speed is what damages off road.

I am not advocating the need for diff lock or indeed 4motion, my FWD golf has been all over the snowy mountains this winter pretty well, but if you have 4motion on the basis that you feel you may want it for that occasional off road trail, then get the diff lock as without it you might as well be FWD. Also there is a premium for vans with diff lock in the second hand market so could be worth the small additional cost. talking to the dealers here in Central Europe, 90% of the Californias they sell are 4motion with diff lock.

 

[Jandy61]

I ordered a 4motion to give Better traction on the road when wet, cold and snowy. for most U.K. owners there’s not much ground you can legally drive onto that requires a diff lock, I’d rather spend 750 quid on second set of wheels and tyres.
Also what I don’t understand is why there is no electronic centre diff?
We have a 2015 skoda Octavia estate all wheel drive, there’s a button on the dash you can press and it optimises the all wheel drive drivetrain even more, by splitting drive, to the front and rear, reduces the throttle response and adjusts the abs system, etc, the max speed is 30 kph for all this to work.
Odd the 4Motion hasn’t got this type of system

 

[Tarquers]

I ordered a 4motion to give Better traction on the road when wet, cold and snowy. for most U.K. owners there’s not much ground you can legally drive onto that requires a diff lock, I’d rather spend 750 quid on second set of wheels and tyres.
Also what I don’t understand is why there is no electronic centre diff?
We have a 2015 skoda Octavia estate all wheel drive, there’s a button on the dash you can press and it optimises the all wheel drive drivetrain even more, by splitting drive, to the front and rear, reduces the throttle response and adjusts the abs system, etc, the max speed is 30 kph for all this to work.
Odd the 4Motion hasn’t got this type of system

there is no centre diff because of the haldex on the rear and the fact that all 4motion vehicles are primarily FWD. Centre diff is typical for RWD vehicles with an option to make them FWD through an additional driveshaft. The Skoda system you describe is a haldex on the rear axle being partially engaged. Cars like the golf R use a partial engagement of the haldex to provide something closer to 50/50 bias. Equally changing the throttle response limits the chance of wheelspin to provide control electronically.

 

[bvddobb]

One wheel in the air, or even on wet grass, is enough to put the 4motion to make it necessary to use excessive speed to get out of a sticky situation.

4motion is designed for on road scenarios, so in the instance where there is a loss of traction on the front wheels causes spin, power is sent to the rear through the haldex clutch and reduces spin. Same scenario in towing where the front wheels are light, more power goes automatically to the rear to aid traction.

When you get into a scenario when one wheel lifts, the system will try to use the brakes to stop power being lost through the spinning wheel (6:23 in the video in post 24). You will get a lot of wheel spin before the system kicks in, and it will start and stop again each time you change throttle position.

Switch off ESP when in a difficult situation, so all the on-road scenario's in the software don't kick in (so it won't think you are aquaplaning or spinning on a wet and slippery road or something, and reduce traction when you actually want it, etc), and you'll be surprised...

That's the first thing they teach you in a 4M off-road training: switch off ESP!

 

[Jandy61]

Switch off ESP when in a difficult situation, so all the on-road scenario's in the software don't kick in (so it won't think you are aquaplaning or spinning on a wet and slippery road or something, and reduce traction when you actually want it, etc), and you'll be surprised...

That's the first thing they teach you in a 4M off-road training: switch off ESP!

And that goes for 2 wheel drive also

 

[WelshGas]

there is no centre diff because of the haldex on the rear and the fact that all 4motion vehicles are primarily FWD. Centre diff is typical for RWD vehicles with an option to make them FWD through an additional driveshaft. The Skoda system you describe is a haldex on the rear axle being partially engaged. Cars like the golf R use a partial engagement of the haldex to provide something closer to 50/50 bias. Equally changing the throttle response limits the chance of wheelspin to provide control electronically.

Not quit correct. 4Motion is predominantly RWD at start up.

Permanent 4MOTION

All-wheel drive is engaged whether you’re on or off-road. In normal circumstances, the Torsen differential distributes power 40:60 between the front and rear wheels, but when off-road, the system automatically distributes power to the wheels with the most grip. When combined with other systems such as Hill Start and Hill Descent Control, you’ll find your vehicle virtually unstoppable.

4MOTION All-Wheel-Drive Technology | VW Vans

Explore the Volkswagen’s 4MOTION technology, designed to maintain traction while off-road with improved road holding and safety in poor surface conditions

www.volkswagen-vans.co.uk

 

[briwy]

See our avatar. Used it then and it's been used a couple of times of very muddy campsites.
I've posted this video before but didn't need to use the diff lock then. Not a good idea on bends anyway.

 

[Tarquers]

Not quit correct. 4Motion is predominantly RWD at start up.

Permanent 4MOTION

All-wheel drive is engaged whether you’re on or off-road. In normal circumstances, the Torsen differential distributes power 40:60 between the front and rear wheels, but when off-road, the system automatically distributes power to the wheels with the most grip. When combined with other systems such as Hill Start and Hill Descent Control, you’ll find your vehicle virtually unstoppable.

4MOTION All-Wheel-Drive Technology | VW Vans

Explore the Volkswagen’s 4MOTION technology, designed to maintain traction while off-road with improved road holding and safety in poor surface conditions

www.volkswagen-vans.co.uk

It’s not a Torsen it’s Haldex. That reads like a description of the Touareg centre diff (Torsen).

Edit: checked the link it is for the Amorok.

 

[Tarquers]

Not quit correct. 4Motion is predominantly RWD at start up.

Permanent 4MOTION

All-wheel drive is engaged whether you’re on or off-road. In normal circumstances, the Torsen differential distributes power 40:60 between the front and rear wheels, but when off-road, the system automatically distributes power to the wheels with the most grip. When combined with other systems such as Hill Start and Hill Descent Control, you’ll find your vehicle virtually unstoppable.

4MOTION All-Wheel-Drive Technology | VW Vans

Explore the Volkswagen’s 4MOTION technology, designed to maintain traction while off-road with improved road holding and safety in poor surface conditions

www.volkswagen-vans.co.uk

This explains it from VW. Front wheel drive except when it isn’t.

 

[California4x4]

California models are called Beach, Coast, Ocean. Not Sahara, Serengeti, Safari or Rainforest. Could that be a hint ?

Having lived in Africa, I’d take my 4Motion Ocean (with diff-lock) to the Sahara or Serengeti before I’d put it on most beaches or in the ocean

 

[California4x4]

I am not an off-road expert, but it seems clear that a diff lock is needed when a wheel has completely no traction spinning off the ground. It has to be quite a dramatically uneven terrain where a front wheel lifts up and you could only proceed, if you could not carry any momentum, by engaging the diff. lock.
Before I would venture in such terrain, I would personally upgrade suspensions and tyres before thinking about diff lock.

The problem is, you can’t upgrade from no diff lock to a diff lock. So if specifying from new and you have any intention of going off the beaten track, it makes sense to me to go for a diff lock. As you say, there are lots of options for lifting suspension and protecting the vulnerable underbelly and fitting suitable tyres after purchase if you need them.

 

[Kernowboy]

Afraid that is not the case, because there is no centre diff lock so any wheel spinning takes all the power so on its own (without EDC) it is no better that 2WD apart from in on road situations. (ready for the flood of abuse here!). One wheel in the air, or even on wet grass, is enough to put the 4motion to make it necessary to use excessive speed to get out of a sticky situation.

Useful thanks, seems to be plenty of different understandings on how 4Mo works, but I still don’t get this statement. If a front wheel slips (within 45 degrees of rotation), drive goes at least partially to the rear so as long as both rear wheels have grip then you would have drive. EDL kicks in to brake a wheel (or both spinning wheels if a rear also loses grip) down the line.
This is the best reference I can find on it, which is pretty clear. It’s old but still seems to cover current 4Mo set up.

 

[B J G]

The Diff Lock only locks the rear axle ie the 2 rear wheels turn at the same rate continuously, this relies on one wheel being on a surface which has traction, no benefit if both wheels have no traction, on sheet ice as an extreme example.
It has no action on the front axle or the transfer of power between front and rear axles.
The 4M does all other actions.

 

[Tarquers]

Useful thanks, seems to be plenty of different understandings on how 4Mo works, but I still don’t get this statement. If a front wheel slips (within 45 degrees of rotation), drive goes at least partially to the rear so as long as both rear wheels have grip then you would have drive. EDL kicks in to brake a wheel (or both spinning wheels if a rear also loses grip) down the line.
This is the best reference I can find on it, which is pretty clear. It’s old but still seems to cover current 4Mo set up.

I like that attachment! great explanation, will be stealing a copy of that for future reference.

It's the ABS sensors that detect wheel spin and trigger the haldex to engage to maintain drive and EDL tries to stop the spinning wheel using the brakes. without the EDL you would loose all drive to the front axle but would have drive at the rear, unless of course you have a spinning rear wheel too then you loose all drive, hence the need for electronic nannies to help out.

Diff lock ignores the electronic nannies by turning them off, and simply locks the rear wheels together and locks the haldex to send 50% of the power to each pair of wheels. A front wheel can still spin, but drive is achieved via the rear axle. I believe that even though esp is off when the diff lock is engaged, EDL still works on the front wheels, i.e., the van will use brakes to stop a spinning front wheel.

 

[Tarquers]

The Diff Lock only locks the rear axle ie the 2 rear wheels turn at the same rate continuously, this relies on one wheel being on a surface which has traction, no benefit if both wheels have no traction, on sheet ice as an extreme example.
It has no action on the front axle or the transfer of power between front and rear axles.
The 4M does all other actions.

yes, but diff lock also forces a power split 50/50 front to rear when engaged (albeit through the electrics).