Thread: 4wd tips

simoncs,

In mud like that there are very few option but to answer your questions.

1. HDC does work in reverse;

2. always best not to simply apply the brakes and slid down as your mate does in the video, as you have absolutely no control. Much better to engage reverse and let it roll backwards in low range using engine braking and with out brakes applied to the point where it is just skidding. Having the wheels moving means you can get some control and traction but this technique is much much harder in practice than in theory as you think you are going more out of control than skidding but you are not.

3. Sometimes simply not going out is the best option. On a surface like that you really have very little control over the vehicle and risk damaging it and the tracks as the get badly chopped up in the wet.

4. FYI the mods will most likely be along soon enough to delete your video due to the use of one expletive, perhaps if you could edit the sound track it would not get deleted due to the G rating of the forum.

Regards,

George

OK, for that section, it sounds like you needed the following:

• Low-Range
• Mud & Ruts
• DSC off

When you're climbing, you need a higher gear as this will increase your speed (momentum) as well as reducing the torque at the wheels. (Torque is the cause of wheel-spin and if you don't have traction, you are going to need momentum.)

As for HDC, turn it on & leave it on, even when climbing hills (it comes on automatically with mud & ruts). HDC works in both forward & reverse gears but you need to have your foot off the brakes as touching the brake peddle overrides HDC.

For a failed hill climb, you need to jump on the brake, pop it into reverse, take your foot off the peddles and let the combination of engine braking & HDC control your descent.

M

Agreed, HDC will work in reverse, but only I think in reverse gear, if you are in a forward gear and sliding backwards it won't do anything. Also agreed that the mud and ruts is the right program.

It can take superhuman self control but for HDC to work properly you must keep your foot off the brakes, once you get on the brakes if it is that slippery it will just lock and slide. But HDC can only do so much if it is very slippery there is a point at which it won't make a lot of difference as it relies on having at least some traction on some wheels, it it has none on any then you are once again just a passenger.

If you are sliding and there are ruts, try and stay in the ruts as they can help guide you like train lines and also slow you a little.

If you have a winch and can get stopped safely and securely on the hill then you might consider winching yourself backwards down it. (Assuming you can't winch up, but only winch up if you know there is a clear route out the other side, otherwise you will have a worse problem if you have to go back down the whole hill again.) If you have a winch and have no choice but to attempt a slippery hill you might want to consider getting your gear out and ready to hook up before you attempt it and position a person in a safe place half way up the hill ready to hook up so the driver can stay in the car with their foot firmly pressed on the brake until the winch is ready to go.

Also agreed that sometimes you just need to accept that you shouldn't be out there and go home, particularly if you don't have mud tyres.

The other thing is, try to resist the urge to put the foot into it, backing off the throttle will increase the Traction controls ability to work better, also if you are following a vehicle up a slippery slope, you won't have the same traction as him if you follow his wheel tracks, his car has broken the surface of the clay down to the really slippery underbelly, it's always the case that the first vehicle will always go up most of the time.

Get some mud tyres, AT's and road type tyres are hopeless on clay, regardless of the fact that the TC is so good, there's no substitute for mud tyres.

Baz.

Uphill on wet, thick clay is generally a no-win situation unless you're running mud tyres. If you _have_ to have a go, then try the following:

Firstly, drop the pressures in the AT's - the tyre will flex quite a bit more, hence throwing off the built-up mud a little easier. I go as low as 18psi, depending on the track (too low and you risk scraping the bottom of the car on the mud, and damage to the tyre). It will make quite a difference to your progress.

If there's a chance of scraping the bottom of the car along the track (which will lose you forward momentum), then if you don't have shortened rods or LLAMS, use the jack trick to raise the vehicle to extended height. This will only work for a few seconds though, so plan everything else first.

You have two choices in your approach: momentum (a fairly fast approach and power on as you climb), or slow and steady (trying not to break traction). The correct choice will be situation-dependent., ie _you_ decide.

If you're taking the fast approach, then use low-range Mud/Ruts, DSC off, HDC on, leave it in auto and try a sensible but reasonably quick approach, rocking the steering from side-to-side as you feel a loss of grip. Never plant the throttle to the floor, just vary the throttle position a little (modulate it) around the half-way mark. Back off a little if traction is restored.

If you need to approach slowly (eg walking pace), then select Rock-Crawl, leave both the DSC and HDC on. Select low 2nd or 3rd and use the same steering/throttle technique as above (athough obviously less throttle as you're travelling slower).


Or you could buy a winch

Cheers,

Gordon

Thanks all for the tips, and sorry mods for the swearing, it wasn't my video to edit.

I think Gordon has the best advice though. I shall have to tell the wife I need a bullbar and winch immediately