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View Full Version : New D4 Owner - Happy & Yeagarup Dunes test



StuWA
10th June 2010, 03:29 PM
My first post as a new LR D4 2.7L owner. Great website - which helped with my decison to buy the D4. Had a 1989 Landcruiser HJ60 wagon for 20 years which gave great service for last 17 years - but family pressure and enlarging rust problem forced the upgrade.

I looked pretty closely at most of the other 7 seater 4wds and whilst all had their pros and cons - the D4 had some great features which appealed to me (and the boss / wife). These included the super refined diesel engine - the quietest and smoothest by far that I have driven - with a good balance of torque / power and economy. The 3L version was tempting but the extra $$s and 19inch wheels kept me with the 2.7L. Compared to the old Cruiser it has twice the power, better economy and a quarter of the noise and vibration - so very happy. Highway crusing is a dream and round Perth also easy to drive and OK economy. Although still getting used to driving an auto.

Another area which the D4 was a standout was the seating. It is the only one with COMFORTABLE seating for 3 in the 2nd row and another 2 (adults even) in the 3rd row. For long trips, the alternatives (Prado, LC, Pajero, Pathfinder, Patrol) had vastly less comfortable middle seat in 2nd row and seats in 3rd row. Which is quite important for oft travelling growing families. Also, I love the rear tailgate setup - esp compared to the side opening Prado, Pajero and Patrol.

As a LR newcomer, I was somewhat uncertain about the 4wd ability (despite the awards) but after a testout down at Pemberton over the weekend I am now reasonably happy with this. Its handling and traction on slippery gravel / loamy / muddy tracks (some steep) was excellent in general 4wd mode and the mud/ruts setting, even on the standard 18inch Conti road tyres it has on, albeit the traction control noises do take a bit of getting used to as first reaction was I had a wheel / brake problem. I had no problems whatever on such tracks - albeit will be good to test later on in winter when the paddocks are even soggier.

Then for the big sand test (which I was somewhat worried about on the lower profile 18inch tyres), we took it down to Yeagarup Beach, over the very loose sand of the Yeagarup Dunes and a steep dune to the beach. We took the farm's old LC trayback with us on this trip - which has much less weight and fatter tyres on 15inch rims just in case - but fortunately didn't need it for a pullout. We let the D4's tyres down to around 16psi , switched off the DSC, raised the suspension height and went for it.

First track up into the dunes I didn't have enough momentum and 10m from the top (after easily getting through a right hand bend half way up the hill) the rear sunk in and tyres spun. We had sunk deep enough for the suspension to have started to push against sand - which clearly wasn't helpful. First lesson - trade off between caution and having enough momentum can only be learned by having a go. We let the tyres down slightly to around 14psi (somewhat cautious still - given lower profile and potential for rim damage or rolling tyre off rim) and successfully reversed down to the bottom and hard ground. Indeed, I didn't try it but I think the D4 might actually reverse better up a hill than going forward on it - as it is quite back heavy when on a steep incline due to axle locations and weight distributions - and i think would have bettre weight distribution in reverse. Something to try in emergencies.

With a fair bit more speed (more than needed for the Cruiser) and sticking to previous track marks, I attacked the dune entry hill again and successfully floated all the way to the top (with just a little bit of wheel sinking just before top) - using the sand driving setting - although I am not sure it actually adds too much when you are going OK. Driving around the top of the dune system was relatively easy - with the sand more compacted and slopes much more benign. Track down to the beach was handled well - albeit I was continuously worried we might roll a tyre off rim boucing along the harder sand tracks through vegetated dunes - but fortunately my fears were foundless.

Steep sand descent down to beach was also handled well at slow and steady pace - with traction control working well albeit quite noisily. Beach was beautiful as usual. Drove down to Warren River mouth but stayed 100m or so back and we have seen / heard of many sunk cars getting too close here in winter / spring.

Steep dune out successfully attacked OK first time with PLENTY of momentum and a bit of steering zig zagging near top (as started to slow a bit) - and then the exit from dunes was simple.

So, all in all - not as good on the dunes as the old cruiser - which I put down to 18inch v 15inch tyre footprints - I happily let the cruisers tyres down to close to 10psi - but this is a confidence thing. Also, the rear weight distribution (with 4 passengers mind you) going up hills seemed to put alot of weight on rear end. So just need to be more careful to maintain plenty of momentum going up soft sand hills - but otherwise should be OK. Looking forward to testing in some tougher mud conditions in spring and dunes at peak of summer - when sand is even drier.

I would be interested to hear any other D4 sand driving experiences.

StuWA

rmp
10th June 2010, 07:52 PM
Hi Stu

Welcome to the forum and wow...what a great first post!!!

Couple of things -- all else being equal the contact patch is the same regardless of rim size, but the rim gets closer to the ground with low-profiles. This is an oft-discussed topic so no more on it, please search the numerous recent thread for more where you'll also find many discussions on sand driving.

Re reversing to make it up hills -- don't. The transmission is weaker at the front than the rear, and is also weaker in reverse than going forwards. Drop even 2psi more out of the tyres and that can work very well. If it's dire drop the fronts down to 8 and the rears to 10 (yes even on 18s), dig out ruts so you tramline, remove weight (passengers). Reversing is not the answer. A set of Maxtrax will be useful too. Air up to 16-18 once you're through the hard part.

The comparison with the 60 is interesting. A lighter vehicle, tyres right down to 10 but little power vs a heavier, more powerful car that can't air down that far. In the tight twisty going where the D3 can't use its power the 60 could be a winner.

gghaggis runs training courses and I suspect you could do a lot worse than get out and about with him for practical training.

Celtoid
10th June 2010, 08:54 PM
Hi Stu

Welcome to the forum and wow...what a great first post!!!

Couple of things -- all else being equal the contact patch is the same regardless of rim size, but the rim gets closer to the ground with low-profiles. This is an oft-discussed topic so no more on it, please search the numerous recent thread for more where you'll also find many discussions on sand driving.

Re reversing to make it up hills -- don't. The transmission is weaker at the front than the rear, and is also weaker in reverse than going forwards. Drop even 2psi more out of the tyres and that can work very well. If it's dire drop the fronts down to 8 and the rears to 10 (yes even on 18s), dig out ruts so you tramline, remove weight (passengers). Reversing is not the answer. A set of Maxtrax will be useful too. Air up to 16-18 once you're through the hard part.

The comparison with the 60 is interesting. A lighter vehicle, tyres right down to 10 but little power vs a heavier, more powerful car that can't air down that far. In the tight twisty going where the D3 can't use its power the 60 could be a winner.

gghaggis runs training courses and I suspect you could do a lot worse than get out and about with him for practical training.

Don't want to start another Rim War but 'All else being equal' would there be any point of letting your tyres down if the contact patch remained the same. Surely this would only be true on a very hard surface. Once your tyre sinks (into sand or mud), doesn't the side wall become part of the contact patch? If you reduce pressure and the tyres bulge, doesn't the lower surface of the bulge take part of the overall weight? Isn't that the point of the exercise? Isn't that the core of the many discussions? The larger the tyre wall, the more bulge, the bigger the contact or footprint? As to how much difference that really makes....well I think that's what's being discussed until the cows come home. :)

rmp
10th June 2010, 09:03 PM
"all else being equal" -- contact patch is the same regardless of profile if the vehicle weight, tyre diameter, width, construction are all the same. So 20psi footprint would be the same for both. Just rim gets closer.

As you say this has been covered in great detail elsewhere (those interested please search instead of continuing this particular point and post any follow in a Rim Discussion thread not here) so back to hearing about Stu's experiences with his D4.

Celtoid
10th June 2010, 09:10 PM
"all else being equal" -- contact patch is the same regardless of profile if the vehicle weight, tyre diameter, width, construction are all the same. So 20psi footprint would be the same for both. Just rim gets closer.

As you say this has been covered in great detail elsewhere (those interested please search instead of continuing this particular point and post any follow in a Rim Discussion thread not here) so back to hearing about Stu's experiences with his D4.

Good point, how about you explain your point on the sand driving or rim discussion thread please?

Would love to hear more about Stu's experiences.

StuWA
14th June 2010, 12:37 PM
Thanks for the tips Rmp. The reversing was only a suggestion as a last resort - based on my experience of definite rear tyre sinking issue ascending sand hill due to weight distribution - but good to know about the transmission. I'll try going down to 10psi next time on the soft sand - and see how that goes. Next trip is up north WA so shouldn't have any issues there. Will find rim discussion thread for further comments on rims - though from both observation and simple geometry I disagree on the footprint matter - same diameter tyre on 15inch rims has a larger tyre air volume to surface area ratio than on 18inch rims - and therefor footrpint will be larger as pressure reduced - but difference will not be that material.

tunnelthug
17th June 2010, 12:14 PM
Sounds like a great day out, StuWA!

Interesting observation with regards weight distribution; I wonder how much more of an effect there is when towing a trailer.

About 2 years ago I was driving over on Moreton Island and assisted in de-bogging a D3 towing a boat - he had got stuck on a soft section at one of the entry points onto the main beach on the landward side where there was a tricky tight bend to get round also. I was driving a mate's Prado at the time and almost wept with shame giving the D3 a snatch out - I had previously been extolling their virtues and they have always been my dream car! He had obviously lost momentum with the trailer as he went through the corner and had dug himself in.

The driver didn't own the vehicle and was new to sand driving - I suspect they still had the DSC on and hadn't let enough air out, coupled with the weight of the boat and trailer....that's my excuse on his and the D3's behalf!

Tyre pressures/ rim size - dropping out pressure increases length of contact (increasing contact area - bagging of sidewalls not really a factor so far as I understand) - check out Roothy's Fraser Island DVD from 4WD Action magazine - they go into this in some detail, particularly when towing a trailer on sand - pressures will be different between vehicle and trailer, but what you want to aim for is similar contact length on the ground (so they say...!) Issue with larger rims of course is increased risk of rolling the tyre off at lower pressure, hence nor able to drop out as much air.

Cheers!