Proper Technique?

[RoverMack]

Unless you have someone with more skills than you that allows you to tag-along, IMHO you are opening yourself up to bad habits.

Canada isn't that far from some of his Eastern locales...

I was fortunate to hook up with some very experienced drivers, Marc Olivares, Steve Rupp and Rob Davison who have taught me everything I know. Although I would still like to take a proper class from Bill Burke, if not for the experience, for the fundamentals that sometimes get passed up in real world events.

Best $ spent on improving my RR's trail ability was with Bill and his driver training, photos; see 4 wheeling America album at http://spaces.msn.com/conalmack
The trick is learning from the "right" people.

 

[Scott Brady]

Bill Burke is a class act. A great trainer and world-class spotter. It will be money well spent.

 

[Alaska Mike]

I'm not sure there is a "proper technique". What worked for me in the Paciic Northwest didn't in the Southeast, and what worked there was different from what did the trick in Alaska. "Mud" or "rock" are very different things in different areas. There's no substitute for stick time and a lot of trial and error.

However, there are some techniques that work in a variety of circumstances. I have yet to buy a video that I get much driving technique from. I learn much more from being there and having someone show me firsthand how to do something. It doesn't have to be formal training, as long as the people doing the demonstrating are better drivers than I am (isn't hard for me to find).

 

[ntsqd]

Bill Burke is a class act. A great trainer and world-class spotter. It will be money well spent.

Exactly my experience with him on the Dusy-Irshim in the snow.

 

[madizell]

The internet is the wrong place to be asking about techniques...

I pretty much agree with that, and with the thought that watching video doesn't teach much either. Field work is the only way to learn driving technique, and even then you will need a mentor you trust and whose suggestions you will at least try several times. I have known folks that could not cross muddy areas to save their souls, in spite of constant tutoring, only to have them one fine day listen for the first time, try what was being suggested, and pop right through an obstacle that stopped them every time before. The look on the face was precious, like -- hey! It worked! No kidding...

Not to mention that for any given obstacle there are more than one way to overcome it, and that no one technique works every single time even on the same obstacle. On the net, at best you will get generalities. Timing, momentum, choice of line and the affect it has on progress, are all things that you need to experience to grasp correctly.

As for tire pressure, if you have a means of airing tires and reseating beads on the trail, drop your pressures far lower than you are using now. 20psi is still in the street pressure range. The most obvious problem with dropping pressure is unseating the tire, not slashing the sidewall. If you don't spin up the tires in sharp rocks, the chances of cutting the tire are lower than you think. Width of rim versus profile of tire has a profound impact on how well the tire stays on the rim. Here, narrow rims work better than wide rims, and with 33x12.5x15's I have covered miles of difficult trails with only 8 pounds of air and no lost beads because I was using relatively narrow 8 inch wheels instead of the recommended 10 inch. Nevertheless, if you are constantly unseating a tire due to low air, raise the pressure, but until you get down to the point where having the tire come off the rim is a problem, you are not low enough. If you can not reseat a bead on the trail, you will have to learn how to drive rocks with hard tires.

 

[R_Lefebvre]

I'm not sure there is a "proper technique". What worked for me in the Paciic Northwest didn't in the Southeast, and what worked there was different from what did the trick in Alaska. "Mud" or "rock" are very different things in different areas. There's no substitute for stick time and a lot of trial and error.

That's kinda what I thought. It's the same with high performance driving. I never found an instructor who could teach me as well I as could teach myself with just seat time. I have never crashed, never broken the car, and have had very few "offs", and yet I'm pretty quick. I'm kind of approaching this the same way.

So, in this regard, I just wanted to make sure I'm on the right track here. I will pick up the "feel", I just need some details on some technical bits.

I also taught myself to TIG weld without instruction. Just read some good texts and had at it. It's just the way I work.

Here's a picture of the rear tires with 15psi. What do you think? Seems to me like any rock with a sharp pointy bit facing up is going to be a problem.

 

[madizell]

Here's a picture of the rear tires with 15psi. What do you think? Seems to me like any rock with a sharp pointy bit facing up is going to be a problem.

Have some faith in your tires. Certainly you don't want to abuse the sidewalls, but there is no way to air down without a sidewall bulge no matter whose tires you use. Some brands and builds are more susceptible to cuts than others, and if sharp rocks and low pressure is something you do a lot, you will need to find a tire that can take that and survive, which is why I like bias tires for hard off road work. Still, I don't see an issue with the bulge. Keep your tires on top of larger rocks, stay away from areas that will wedge the tire between rocks, and go easy on the gas. Monitor the sidewalls until you are comfortable with the fact that they can take scuffing without getting deeply cut. If you get into a jam, use your winch to get out rather than smoking the tires. Carry a spare.

Besides, with low pressure in the tire, even if something pointy contacts the sidewall, it won't have a lot of resistance to offer and will give instead of puncture. Usually. It is easier to cut a hard tire than a soft one.

 

[sinuhexavier]

Besides, with low pressure in the tire, even if something pointy contacts the sidewall, it won't have a lot of resistance to offer and will give instead of puncture. Usually. It is easier to cut a hard tire than a soft one.

Good point, like popping a totally full water balloon as opposed to a half full water balloon.

 

[R_Lefebvre]

I see. Thanks.

I had been thinking about the just winching over difficult stuff idea. Wasn't sure if that's just being a wuss, or smart.

The stick/slip I was talking about on the wet rocks, it wasn't severe for sure. Very light. In fact, I had the same thing happen doing a very steep sand climb. I had run out of momentum at the top and stopped moving forward. The tires were clawing down and then I got the stick/slip vibration going on. Is that really damaging/risky? Or is it fine? This is the type of thing that's hard to describe and I know is better having an expert with you.

Being a mechanical engineer, I have good mechanical sympathy. And it didn't seem like that big a deal. Just wondering if some low level is ok, as long as it doesn't get out of hand, or is it always bad?

I'm just paranoid about the whole axle snapping business.

 

[TeriAnn]

I see. Thanks.

I had been thinking about the just winching over difficult stuff idea. Wasn't sure if that's just being a wuss, or smart.

Do whatever feels right for you and your vehicle. Feel free to tell people you are looking for excuses to practice your winching technique. Winching is a specialized skill that is easy to loose if you don't practice it on occasion.

Land Rovers have full floating axles, so breaking them is no big deal as long as you know what you need to do to keep going in 2WD.

 

[R_Lefebvre]

That was my next question!

I've been meaning to ask that here. I've heard that about the floating axles, then I've also heard my D2 no longer has floating axles? What exactly does floating axles mean?

I get the part about removing the offending driveshaft, and locking the center diff to go in 2wd. But I don't know if/how you have to remove the broken axle shaft.

 

[Redline]

Agree. Most of the time I like 15-psi for slow off-highway work, usually with 255/85R16. Of course the tire size and weight of the rig matter. If you are running that Cooper ST in something like a 265/75, close enough, 15-18-psi seems like a good starting point.

With your mechanical background and vehicle sympathy skills, I bet you can drive lots of places without breakage once you develop and are confident with your feel.

James

Have some faith in your tires. Certainly you don't want to abuse the sidewalls, but there is no way to air down without a sidewall bulge no matter whose tires you use. Some brands and builds are more susceptible to cuts than others, and if sharp rocks and low pressure is something you do a lot, you will need to find a tire that can take that and survive, which is why I like bias tires for hard off road work. Still, I don't see an issue with the bulge. Keep your tires on top of larger rocks, stay away from areas that will wedge the tire between rocks, and go easy on the gas. Monitor the sidewalls until you are comfortable with the fact that they can take scuffing without getting deeply cut. If you get into a jam, use your winch to get out rather than smoking the tires. Carry a spare.

Besides, with low pressure in the tire, even if something pointy contacts the sidewall, it won't have a lot of resistance to offer and will give instead of puncture. Usually. It is easier to cut a hard tire than a soft one.

 

[ntsqd]

Besides, with low pressure in the tire, even if something pointy contacts the sidewall, it won't have a lot of resistance to offer and will give instead of puncture. Usually. It is easier to cut a hard tire than a soft one.

In my experience in desert racing quite the contrary is true when higher speeds are involved. A hard tire moves either the vehicle or the rock or both. A soft tire distorts to failure. Given that I would say that there is no hard and fast rule about tire pressures, ideal pressure completely depends on what you're doing.

I've been meaning to ask that here. I've heard that about the floating axles, then I've also heard my D2 no longer has floating axles? What exactly does floating axles mean?

I've no idea whether a D2 has or doesn't have a floating rear axle or not, I'm no help there.
The distinction between semi-floating and "full" floating axles is whether or not the differential case side bearings carry any of the weight of the vehicle.
In the common to passenger car semi-floating axle design there is one outer wheel bearing that carries the bulk of the vehicle weight, but some is transmitted down the axle shaft to the differential.
The full floating axle is common to 3/4 ton & higher rated North American trucks (& other special cases) has two wheel bearings at the wheel. The axle shaft only transmits torque, there is no vehicle weight applied to it (unless the axle housing is bent). Full floating axles are easy to spot due to their large center hub protruding through the wheel with a ring of bolts or studs & nuts on the end. Removing those fasteners allows the axle shaft to be withdrawn, even if the tire is still load bearing.

 

[Michael Slade]

I had been thinking about the just winching over difficult stuff idea. Wasn't sure if that's just being a wuss, or smart.

When I was doing a lot of location photography for WARN, we would go on a lot of group trail runs. There is a corporate mentality there that is pretty interesting.

If you were on a group run and were the one that had to use the winch, you were basically ridiculed for the rest of the trip.

Trust me, it was all about learning how to drive correctly and negotiate the obstacle with driver skill and technique. Using the winch was *always* the last resort when nothing else would work.

Going to the winch first is lazy and generally a bad idea IMO. You are right, 'seat-time' will cure most of your driving education needs.

 

[R_Lefebvre]

I've no idea whether a D2 has or doesn't have a floating rear axle or not, I'm no help there.
The distinction between semi-floating and "full" floating axles is whether or not the differential case side bearings carry any of the weight of the vehicle.
In the common to passenger car semi-floating axle design there is one outer wheel bearing that carries the bulk of the vehicle weight, but some is transmitted down the axle shaft to the differential.
The full floating axle is common to 3/4 ton & higher rated North American trucks (& other special cases) has two wheel bearings at the wheel. The axle shaft only transmits torque, there is no vehicle weight applied to it (unless the axle housing is bent). Full floating axles are easy to spot due to their large center hub protruding through the wheel with a ring of bolts or studs & nuts on the end. Removing those fasteners allows the axle shaft to be withdrawn, even if the tire is still load bearing.

Ok, that's what I thought with the bearings. And now I know what I've seen on the large trucks.

Ok, so what am I looking for on my Disco to know if it's full-floating or not? This is definitely something I want to learn ASAP. How to remove them if something should happen.