Reply With Quote
Found itOriginally Posted by letherm
OK, I'll admit stupidity up front
I can't find this in the FAQ. I'd like to look at it. Help !!!
Driving Techniques
Why can't I lock the centre diff?
You don't need to, the computer will send torque to the most appropriate axles in any condition. This works very well and people don't feel the need to manually control it, unlike some of the other electronic systems. There is no risk of windup with these vehicles.
What's Terrain Response?
Land Rover's system for changing the parameters of various car controls such as throttle, traction control sensitivity, auto shift points and more depending on what terrain the vehicle will be driven on.
GRASS/GRAVEL/SNOW Function.
Engine Management System.
More progressive throttle map to make it harder to induce wheel spin when setting off & easier to drive smoothly.
Automatic Gearbox.
Automatically sets off in 2nd gear in high range to make it harder to induce wheel slip when setting off.
Automatically selects 3rd gear in low range to make it harder to induce wheel slip when setting off.
Electronic Centre/Rear Differential.
Higher preload settings to reduce the chance of wheel slip occuring.
Hill Descent Control.
HDC is automatically switched on when in low range.
Traction Control.
Has a more responsive & aggressive tune so that if any wheel slip does occur, then it is controlled quickly.
Message Centre.
If a manual gearbox is fitted then the drive is advised to set off in 3rd gear if in low range when a different gear is selected.
MUD/RUTS Function.
Engine Management System.
More progressive throttle map to make it harder to induce wheel spin when setting off & easier to drive smoothly.
Automatic Gearbox.
Starts off in 1st gear, will remain in 1st if light throttle is applied.
Changes up with heavy throttle inputs. Stays in gear & torque convertor locks up when throttle pedal is released. Changes down gears if no throttle pedal input & speed goes below a set threshold.
Electronic Centre/Rear Differential.
Higher preload settings to reduce the chance of wheel slip occuring.
Dynamic Stability Control.
Dynamic stability thresholds are tuned to induce less engine throttle intervention.
Hill Descent Control.
HDC is automatically switched on.
Traction Control.
Traction controls tune is more responsive & aggressive & induces less throttle intervention to control excessive wheel slip quickly. But it allows higher slip levels so that traction can be generated.
Message Centre.
Recommends that low range be selected.
Recommends that the air suspension be raised to off road height.
Steering inputs are displayed when a 1/4 turn of the steering wheel is acheived.
Warns if off road height has been selected & not yet reached.
Warns if off an off road height has been inhibited due to trailer electrics being detected. (not sure if new programming has altered this).
SAND Function.
Engine Management System.
Soft intial throttle changing to more agressive as throttle becomes heavier.
Automatic Gearbox.
The gearbox changes up gears later & down gears earlier to keep vehicle in maximum torque band.
Dynamic Stability Control.
Dynamic Stability thresholds are tuned to induce less engine throttle intervention.
Traction Control.
Traction Control tune induces less throttle intervention.
Message Centre.
Steering inputs are displayed when a 1/4 turn of the steering wheel is acheived.
Warns if off road height has been selected & not yet reached.
Warns if off an off road height has been inhibited due to trailer electrics being detected. (not sure if new programming has altered this).
ROCK CRAWL Function.
Engine Management System.
More progressive throttle map to minimise wheel slip when setting off.
Automatic Gearbox.
Automatically sets off is 1st gear. Holds onto 1st gear longer & changes down to 1st gear sooner to maximise low speed control.
Transfer Box.
Rock crawl is only available in Low Range.
Electronic Centre/Rear Differential.
Has very high preload setings to reduce the chance of wheel spin occurring.
Hill Descent Control.
HDC is automatically switched on. The minimum target speed is automatically selected & the system is more aggressive so as to control the speed quickly.
Traction Control.
Traction controls tune is more responsive & aggressive so that if any wheel slip is detected it is controlled quickly.
Message Centre.
The Driver is asked to select low range.
Steering inputs are displayed when a 1/4 turn of the steering wheel is acheived.
Warns if off road height has been selected & not yet reached.
Warns if off an off road height has been inhibited due to trailer electrics being detected. (not sure if new programming has altered this).
Normal mode doesn't actually switch any of the system off or disable them, it just doesn't put them into any special mode. Hence, traction control etc is always active.
What's the difference in Terrain Response between the D3 and D4?
The D4 has Rock Pre-Crawl (applies brakes up to 5km/h in first and reverse forcing the wheels to turn against the brake).
Sand mode & Launch control: It uses a motion sensor on the chassis to detect when it is moving. Once moving, it'll then adjust the throttle response to make it more aggressive.
How do I drive in sand?
Select Sand mode in Terrain Response and ensure stability control (DSC) is switched off. Use low or high range depending on speed, and consider manually selecting gears, keeping the revs high in the soft stuff. Don't use HDC to descend in sand, come down on the gears, often 2/3 low or first high. Tyre pressure guide:
Rim size / pressure
17 / 16
18 / 18
19 / 20
20 / 22
you can go 50% lower than this in extremis but reinflate as soon as you can. Other variables for tyre pressure are weight and tyre construction. The tougher the tyre, the more you need to deflate it, and the greater the vehicle weight the less you can deflate.
All of the other sand driving techniques that can be found in many places apply.
Also have a read one of our classic threads -> http://www.aulro.com/afvb/d3-d4-zone...ing-wrong.html
How do I drive in deep snow?
Use anything but Snow Mode which is for slippery surfaces, not deep snow. DSC off, and manually control the gears, either second low or first low. If you can use third it's not really deep! Try Normal, Mud/Ruts or if it's a real slog, Rock Crawl and low range, DSC off. Trick the car into Extended Mode by grounding it and wheelspinning slowly, then go into Super Extended. Use Snow mode for a thin, slippery covering on a hard surface.
Can the centre diff be manually locked? Can the rear locker be manually controlled?
Neither can be driver controlled. The computer decides, not you. It actually does a very good job. Most of the time.
Do I need the e-diff (rear locker)?
Impossible to say. If you are buying a new car you'd be mad not to specify it as it cannot be retrofitted and will greatly improve the desirability of the vehicle to offroad tourers come resale, and of course the extra capability. Onroad it makes no difference, but offroad the e-diff can turn a medium track into an easy, and a hard into a medium. Simply, the car does it easier. However, it really only makes a difference in rocky conditions, or on steep climbs. In sand and mud it doesn't really improve performance. If you are shopping for a secondhand vehicle favour those with the e-diff.
Does the ABS work in low range?
Yes, although it will permit a bit of wheel lockup. Which is good.
I want to use an airbag jack. There are two exhaust outlets. How do I plug one of them?
Use a test plug available from plumbing supplies, e.g. TLS431 Plumboss Aluminium Test Plug 5 from Eagles Plumbing Plus. Or buy an air jack that is inflated by a compressor, not by exhaust, eg the Bushranger model.
Return to the table of contents
Bookmarks