Terrain Response & ATSes explained - Part 1 

More detail on various ATSes: l2sfbc.com/ats/

One of the beauties of the systems on older range rovers (late classics, p38s and early l322s), quadra drive jeeps (wj, wk, commanders) was that you had all of their capaility all of the time (apart from low range of course), so the only thing you had to do to go off road was turn the wheel and venture off road. As a car guy I of course love messing around with levers lockers and switches but there is something elegant about that approach especailly on the jeeps that there is no air suspension either and even more on the wj grand cherokee that it's a fully mechanical system that offers partial locking capability on all 3 diffs.

Super helpful. And to your point, testing out personal vehicles in a controlled environment helps understand how the modes work. I had no idea what Toyotas MTS did until I just went out and tried it over and over again.

This is great information! I really like knowing about these systems, even though my vehicle is from 1995 and much more primitive!

Nice representation. So many modes, I got headache 😄. My car has just a lever low/high speed and a rotary knob for front/rear differential locks, that's all.

2006 manual Hilux diesel - High range or Low range - heaven!

This is by the far the best video on traction I ever found on the tube!!! Thank you for this! 🫶🏻

Been waiting for this vid. Thx!

Grass/Gravel/Snow will also cut the power if too much wheel spin occurs so if you want spin you need to turn off DSC or change to Mud/Ruts. Some Land Rovers also have ATPC and Rock Crawl mode even when they don’t have lockers or low range. So just to clarify Rock Crawl doesn’t require low range (Evoque and Discovery Sport). Also Low Traction Launch is great for sand extraction.

Our Discovery 3 engages HDC in sand mode when low range is selected (and re-engages every time you select an off-road program, regardless of your previous setting - very annoying). The throttle in sand mode is very aggressive too, so I'd imagine the tapered throttle was bought in on later vehicles because it's very easy to spin the wheels in sand mode! Rock crawl defaults to first gear and only changes out of first when absolutely necessary. Also, on grass/gravel/snow, it starts off in third gear in low range and second gear in high. It is a very early 2006MY (actually October 2005 build) though, so I'd imagine it's got a lot more clever since then.

Good evening Robert, you may have already covered this, but have you ever done a video testing the load capabilities of wheels and tyres? And possibly the different combinations of sizes for each? For example, a 16inch wheel with more sidewall compared to an 18inch with less. As always, keep up the great work, this research and testing is really informative and eye opening. Thank you

Fantastic video and very useful info. What mode do you suggest using in water crossing? Usually its small rocks/ gravel underneath- hence do you go with mud ruts? thank you

The Land Rover system differs from some or maybe all,as it does not have a manually controlled center diff lock,which can be a downfall in some cases.Sure one can use "rock crawl",and hope it is electrically activated,but is it at all times?

Got a bit confused with the rough and slippery about ice part: I would think you could encounter icy parts offroad that are basically like a field of rocks that got frozen over. Which if rocks are rough that would be too if i understand it correctly. But you said icy can't be rough: So does rough then mean "hard uneven surface with *a lot of traction* for any wheel that has contact?"

Useful video. I guess AI driven selection of the most appropriate terrain is not far away.

It would be more easy to think soft/slipery/rough of the modes would actually be called that way. I found the names of modes quite confusing. BTW, there is no Rock mode in new Ford Ranger, what is the closest mode to Rock?

Great video, again. Ultimately, these systems need wheel spin to make decisions then use brakes to stop it and cut engine power to limit overload. Those would normally be the enemy of forward progress. Black magic indeed.🫣