How effective are chocks when 4X4 static winching? 

Great video as per your usual. Can't wait to see more. I echo many of the comments.

Thanks Robert. In softer soil I've also used the tyres to dig the holes by reversing gently against the winch rope. FYI my diffs are built and with lockers and I'm gentle so I don't blow the diff.

From my observation, the plastic chocks were 'placed' infront of a locked wheel. Thus not allowing the vehicles weight to load up on top of them, so technically you were just pushing them along the ground. I would like to see it repeated, but this time 'LOADING' the chocks, with th vehicles weight prior to the pull. Also some steel chocks are available and should be pre-loaded with the pull vehicle prior to starting the pull. Please repeat this test, but with these new parameters. - Great work always educational, I appreciate your work. thank you

Brilliant as usual ! Loving the shovel comment. And that scratching your head sufficiently is the key point first

Would be interesting a test using scotch blocks.

So, I wonder if the type of chock make a large difference. I have a set of steel chocks with teeth that will actually dig themselves into the ground, and help anchor the truck. There are also miniature versions of the chocks that are used by our large firetrucks that have very aggressive teeth to them. They are cast aluminum and fold up, very impressive chocks.

if you dig the shallow hole place plastic ones in hole roll up on them then they would push against the edge of hole and you would see a large difference

Very informative thanks Robert.

Good information to know. Thanks!

Another informative video!

Now test some scotch blocks like wreckers use. I might weld up some chain hooks to my bumper to use these. Another thing I've done is nose up to a tree next to my winch.

Idea for a video using your load cell... Work out what the towing force is on different surfaces. Ie. How much force can a vehicle "pull" when in sand, on gravel and on bitumen before the wheels spin. High mount point vs low mount point. Uphill vs downhill vs flat.

Very interesting! I once read an article that said that the vast majority of winch pulls, with the stuck vehicle helping, require less then about 1200 kg of force, even hung up on rocks or deep in mud. Hence, the almost complete lack of safety factor on winch cables compared to their winch ratings. Would love to see a test of this type!

You could try putting the chocks in holes with somewhat vertical dug forward wall, letting the chucks dig in. (Keep street pressures in the tires to prevent them from climbing the chuck too easily.)

One day I was winching (Jeep Wrangler - Warn 5 ton) and had the big 'truck sized' chocks from my Unimog handy....they are steel and have some 'shark teeth' on the bottom which really dig into the ground......I thought to myself...Wow that was about 2 x as effective as without.....So I bought another set of these big 'truck' chocks to keep in My wife's Isuzu D Max. In this case I think 'Size' matters🤣.

Adding a comment from Bob Wohlers which for some reason RU-vid wouldn't let through: Robert, good video; specific to just that style of chock. However, as you point out, not all chocks are “created equally.” Some designs do work better than others. That said, I not found that any style of of tire chocks really helps in restraining the movement of a winching vehicle in compression terrain - sand, snow, mud. They do help a bit more in the rocks and on fairly solid uneven terrain since they can eventually “catch” on the terrain and help restrain the winching vehicle. If I really need to restrain the movement of a winching vehicle on compression terrain, I almost always anchor the vehicle from behind by running a winch line extension from the front bumper under the vehicle to the rear. One more item if I may… IMHO I don’t believe any video or mention of restraining a vehicle while it’s winching should conclude without noting for beginners that they should never leave a static winching vehicle’s automatic transmission in PARK during a pull. I don’t believe I heard that mention in your video; perhaps I missed it. As you know, leaving a winching vehicle in PARK to restrain it is asking for a broken Parking Pawl - a major transmission meltdown in the field. Now you really have a stuck vehicle. Cheers.

You could try using chocks that are properly designed for off-road use. A proper off-road chock is a single piece of Steel bar bent into the shape of a chalk with teeth on each end to dig into the soil. That being said I carry one for use while jacking, but would only use it while winching as a very last resort.

This is great, thanks for doing all these tests with actual measurements! Have you ever tried winching with chocks (maybe on all 4 wheels) without any brakes or parking brake, letting the vehicle roll? I wonder if heavier duty rubber chocks used in that way might provide more traction than the tires alone.

There are vehicle anchors and there are vehicle anchors. The only ones I have seen that actually work were those made by Fairey Winches Ltd. (later Superwinch Ltd.), and used to be sold through Land Rover dealers under Part Number 583590 - sadly now obsolete but very desirable used. Those you actually physically drove on and put a chain over your front bumper. They are also very heavy, bulky and quite cumbersome. Most seem to be glorified wheel chocks which don't work.

I love your stuff, I bought the factor 55 soft shackle after watching your vid, but i have to say on this video you used lightweight, non serious looking chocks. If we look at the Fairey Wheel Chocks, - them are chocks, those are real chocks with a blade to dig into the ground. Your yellow plastic ones, you might as well have put the front wheels on a skateboard. Sorry I dont mean to be mean, apologies. Just that I was looking at the Fairey chocks and then I watched this. All hail the dozer blade.

It worth to test if low tire pressure adds friction.

As always, you try to explain different scenarios in the most scientific way possible. I do not know how many times you have performed the test in each of the chock scenarios; I say this because the images of the plastic chocks test seem to show that it is performed on a footprint from a previous test (3:50). On the other hand, I wonder if the caravan chocks used in the test would do a better job of removing the underneath layer of gravel by allowing their saw claws to dig into the dirt better. Be that as it may, I like the idea contributed by @Sten Torsten Michael Kruse about digging a hole with a vertical wall on which to support the plastic chock (or stone) and thus prevent the chock from sliding. I also wonder what effect it would have if in that hole dug we placed the plastic chock upside down and placed with the approach edge facing forward and digging into the hole as the tire rests and pushes the opposite vertical part of the plastic chock. As if the leading edge turns into a large claw as it digs into the hole. I do not know if I have explained myself correctly so that you can get the idea of ​​what I intend to convey. Regarding the use of stones, it is evident that we have to adapt to those that exist in the environment, trying to use those that are larger, with a flat vertical face on which the tire rests and with another more irregular face that is keyed in the terrain as the car's support on the stone increases. Another option is to use a trunk of a fallen tree, or a piece of a fallen branch, from which other branches come out that can be cut, in such a way that the latter dig into the ground like claws. Editing my comment: I'm sorry. I forgot to thank you for your work, not only for what it contributes in itself, but also for the possibility of contributing ideas and discussing them.

Tyre pressures seems to be the obvious one to test next....this is partly about breaking traction and partly about maintaining resistance (friction) after that initial traction is broken. I would think both footprint and tread would play a large role?

I think you should use different types of tire chocks. Different materials such as rubber chocks will do better.

How about putting the wheel chalks in the hole? Or, turning some branches into stakes and then driving the front wheels up to them? Also, can you damage the parking brake pin by leaving the vehicle in park instead of just using the E brake?

Maybe a length of wood/tree branch across the whole front of the vehicle or two 500mm or longer to increase the frontal area of the resistance?

Little harder to test but what about multi vehicle anchors? And what about trying to reverse power in a winch pull?

another great one. When i am by myself, i find it hard to push the break lever when i am outside with the remote winch control, so the chalks might be better than only the rear wheels (e-brake). Is there a device to apply the breaks on all four wheels without being in the cab? I am planning on puling out some shrubs, and want to see what is going on out of the cab.

you didn't use the plastic ones to their full potential for them to work the vehicle needs to be able to roll up on them to put downward force to make them dig into the ground the way you did it the wheel was just pushing the plastic

✋😁 Question: What's a brain?

The irony… mentioning a brain as a recovery tool… then digging a hole with the shovel and not placing what is dug out to the front of the hole… 🤦‍♂️ why not use what you work for? Free loose dirt to chock a tire with