Difflock vs Traction control

[MarcR]

Aha....

Actually very surprised that they have discontinued the diff lock on the bakkies, maybe using the same drive train as the Prado now.

Just thinking aloud here...

We tested a VW Touareg in an axle twister on a very well manicured fine lawn... the control is so precise that there was no damage to the lawn at all, only the indentations from the weight of the vehicle... that is a high end system.

We did not attempt the same feat with any other vehicle... I stand to be corrected but we were concerned that the double cabs at hand, both DL and with traction control would get us into trouble^[1]...

The earlier traction control in the double cab type vehicles was pretty rough... the new ones are much finer, approaching the SUV (Prado) levels.

The earliest "offroad" Touaregs (the ones with air suspension option) had diff locks, but now there are none... DL and TC do not work together so I think it is going to be interesting to see how manufacturers see fit to let the simple DL go. I can see how manufacturers would see the DL as just an added problem... the question is how will missing old school DL on the vehicle spec affect buyers now?


1. We have since tried a similar experiment on not such a nice lawn and the results were not so pretty. Not an exact comparison, but even the vehicle with DL "disturbed" the grass.

[JohanMaree]

Just thinking aloud here...



The earliest "offroad" Touaregs (the ones with air suspension option) had diff locks, but now there are none... DL and TC do not work together so I think it is going to be interesting to see how manufacturers see fit to let the simple DL go. I can see how manufacturers would see the DL as just an added problem... the question is how will missing old school DL on the vehicle spec affect buyers now?

My previous Gwagen (1981) had difflocks front and rear. Obviously at that time TC did not exist.

My present Gwagen has both difflocks front and rear AND TC. Interestingly the TC is always on and working until the center diff (CD) is engaged which then switches the TC off. It seems the computer then senses that the driver wants to do serious off-road where TC is not a good idea. The car then carries on without TC whether DL is engaged or not. As yet I could not find fault with this set-up.

I have found that driving at cruising speed on gravel roads with CD engaged is not comfortable. Much better with CD off and TC on. One can sometimes feel how the TC works under you, like in going into a turn a bit faster than one should.

Maybe MB is cleverer than what we stand to believe.

[bertus]

If you dont have difflock you apply the handbrake to force the diff to lock

[AceVentura]

This is one of the things I love about the FJ. In low range, you can enable A-TRAC on all 4 wheels. If you then engage rear diff lock, TC obviously disengages for the rear axle, but A-TRAC stays on the front wheels. Best of both worlds, and turning circle not impacted at all.

But the FJ is permanent 4WD?

[pjf110]

But the FJ is permanent 4WD?

Nope FJ is selectable.

[4x4tripping]

Which one’s AWD system is better in large premium SUV class? You’ll find the answer in this video: Land Cruiser 200, GLS 450, LX 570, QX80, Range Rover, BMW X7, G63 in absolutely stock configuration:


https://www.4x4tripping.com/2021/02/...eiten.html?m=0


Do we still need lockers on newer cars with 4x4 drive? Guess most of us - not...

4x4tripping

[DCTheron]

Which one’s AWD system is better in large premium SUV class? You’ll find the answer in this video: Land Cruiser 200, GLS 450, LX 570, QX80, Range Rover, BMW X7, G63 in absolutely stock configuration:


https://www.4x4tripping.com/2021/02/...eiten.html?m=0


Do we still need lockers on newer cars with 4x4 drive? Guess most of us - not...

4x4tripping

If I have to struggle like those guys I'll go sit in a corner and cry myself to sleep. Buy a proper 4x4 if this is what you want to do

[WernerDL]

I remember the very first time I took the PS off road on an obstacle course. The first obstacle was a nice bit of wheel articulation on a steep uphill. So the trainer guy says to remember to put your difflocks on. First goes a Jimny with HT's and makes it with just a little wheelspin.

My turn, suitably nervous. I forget the put on the difflock and just head up the hill in 4LLc. No problems, no struggle, no wheelspin.

So who knows how necessary a difflock still is these days with all the magical electronic trickery going on beneath you.

[MarcR]

..
Maybe MB is cleverer than what we stand to believe.

It definitely is... and those of the other high end SUV manufacturers... TC systems are built on AI principles^[1] and for the most part are more capable than humans... these vehicles showcase the capabilities of the marque.

The question is how will manufacturers balance the additional cost vs. effectiveness of DL against new buyers perceptions in the much more competitive Double Cab market?

My current vehicle has to come to a stop to engage DL or engage the front wheels by means of a short stick next to the gear lever... it will not be difficult to persuade me to give the DL a miss on my next bakkie.




1. I find this to be a very functional description of AI... https://www.investopedia.com/terms/a...ligence-ai.asp

[antonagel]

have a look at the youtube video to see how good the active traction control on toyota is.

https://youtu.be/GgX_8G3JwjE

[grips]

So yes traction control will be better doing slow stuff like mud and rock crawling then a rear diff lock. As Francois have pointed out in these conditions with a rear locker only you are left with an open front diff that does not mean much traction wise.

Once you need speed and momentum TC becomes pretty much useless like in sand and dune driving. Rear locker will be the better weapon to use.

TC becomes absolute in all conditions when you have a vehicle with front and rear lockers.

[rechardt]

I remember the very first time I took the PS off road on an obstacle course. The first obstacle was a nice bit of wheel articulation on a steep uphill. So the trainer guy says to remember to put your difflocks on. First goes a Jimny with HT's and makes it with just a little wheelspin.

My turn, suitably nervous. I forget the put on the difflock and just head up the hill in 4LLc. No problems, no struggle, no wheelspin.

So who knows how necessary a difflock still is these days with all the magical electronic trickery going on beneath you.

yeah good point.the electronics are beginning to spoil us.

[rechardt]

have a look at the youtube video to see how good the active traction control on toyota is.

https://youtu.be/GgX_8G3JwjE

The fortuner sums it up as far as my Hilux is concerned. good Video

[ChasingSunsets]

So yes traction control will be better doing slow stuff like mud and rock crawling then a rear diff lock. As Francois have pointed out in these conditions with a rear locker only you are left with an open front diff that does not mean much traction wise.

Once you need speed and momentum TC becomes pretty much useless like in sand and dune driving. Rear locker will be the better weapon to use.

TC becomes absolute in all conditions when you have a vehicle with front and rear lockers.

Absolutely, the TC in my Paj eats up just about every type of terrain except very rough sand obstacles that involve articulation and require momentum. The articulation unloads the wheel and allows wheel spin which causes TC to brake the wheel and rob momentum. In these scenarios I wish I had the GLX with the rear-diff lock which completely disengages the TC and would allow me to use the power as needed. As it stands I am going to modify the TC so that I can switch it off completely under certain scenarios. I guess its a case of learning the vehicle and getting used to what works best in that car.

I have seen with my friends older 4.0v6 hilux (no TC) that if the rear diff-lock was removed he would get nowhere on certain obstacles. If he forgets to engage that rear diff in sand he just spins out most of the time. Forget about axle twister type obstacles without the rear diff engaged (yes I know you can left foot brake). With the rear diff engaged he just monsters it all.

[Hooly]

I have watched may videos over the last couple of days as a result of this thread.
What I have derived from best to worst systems is the following.

1. Low range. Full diff lock front, center and rear. This will cost you R2mil plus, only one vehicle I know of, offer this.
2. Low range. Diff lock front and rear. Traction control. This will set you back around R1mil
3. Low range. Diff lock rear in combination with traction control. I have one of these about R800k for a new one.
4. Low range. Diff lock. Most bakkies and bakkie based suv's offer this. From about R500k
5. Low range. Limited slip diff. R400k plus. With or without traction control.
6. Low range. Traction control without diff lock or LSD. (Jimny)R200k
7.Low ratio 1st gear. 4wd lock front and rear together. Traction control.R250k Duster, Subaru, Jeep Renegade Trailhawk, Amarok.
8. 4wd locking front and rear together with no low range or low ratio 1st gear. Traction control. X- Trail.
9. Front biased awd with traction control and a cvt gearbox. (most "4wd" softroaders)

Did I miss anything?

[Francois Theron]

Did I miss anything?

Low range: Diff lock front and rear, no TC ala Land Cruiser 76 and 79. Still the best option IMHO

[Hooly]

Low range: Diff lock front and rear, no TC ala Land Cruiser 76 and 79. Still the best option IMHO

Little to no electronic stuff that can fail on you. Would be my top option to tackle dark Africa.

[HeinrichC]

So much talk and no practical comparison evaluation by forum members, time to put your money where your mouth is

Why not setup a 4X4 Community practical challenge on a 4X4 trail with various obstacles, proper cross axles on a steep hill with lose rocks, sand, etc.

Only one rule - The vehicles entering the challenge must be stock standard i.e. no mods/changes to the engine, suspension or tyres.

I'll enter my Rubicon in the challenge. It has both ie TC and front&rear lockers.

[Hooly]

So much talk and no practical comparison evaluation by forum members, time to put your money where your mouth is

Why not setup a 4X4 Community practical challenge on a 4X4 trail with various obstacles, proper cross axles on a steep hill with lose rocks, sand, etc.

Only one rule - The vehicles entering the challenge must be stock standard i.e. no mods/changes to the engine, suspension or tyres.

I'll enter my Rubicon in the challenge. It has both ie TC and front&rear lockers.

I'm in, I know you will kick ass, but I would like to see what my stock Cherokee Trailhawk can do.

[faniedup]

Little to no electronic stuff that can fail on you. Would be my top option to tackle dark Africa.

Is there data that shows electronics to fail more than mechanicals in a vehicle?

My D4 in just short of 200k km's had a diesel housing failure (crack) that caused false water in diesel warnings, and a faulty water resorvoir failure that gave false low water warnings, a bit hybrid in my opinion. The balance of maintenance related items were all mechanical ie brake disks, suspension bushes, etc. Have not yet replaced a light bulb.

I think the fear of electronics is overrated, we take electronic navigation aids, fridges full of electronics, digital cameras, solar panels with electronic controllers etc etc on our trips, and it survive.

Personally I think electronics are more reliable than mechanics in most cases?