I know that offroad tyres are the bane of a Sport owners existence and I for one am still struggling to get satisfactory mud profile rubber under the guards.

Before I go too much further experimenting, does anyone know just how far you can actually push it when it comes to overall tyre size?

What is the maximum diameter and tyre width you can run?

Thanks in advance

Jimmy

Footnote: When working out the calcs I need to consider that i've just purchased the LLAMS height controller and a set of Johnson lift rods that are both being installed tomorrow so I will have a minimum 2.5 inch (lift. I would however like to use the LLAMS to still be able to lower the car 20mm for shopping centres (i have racks on top so will be approx 2.1m with lift installed. 'Black Betty' Java Black RRS 07 TDV6

Last edited by Jimmy Salsa on Thu May 12 2011 10:28am. Edited 1 time in total

The answer depends on how much modification you're prepared to do, and whether you're talking about a pre-2010 car or 2010/11.

For a pre-2010 with no mods, widest tyre (if you're using it offroad) would be a 285mm. For all years, just under 31" diameter will fit with no mods.

If you're prepared to do a fair bit of cutting of plastic (the inner wheel well liners, + front bib) and bend a few bits of metal, you can squeeze 275/65R18 muddies in (32.5" diameter), but you'll need either the shortened rods or the LLAMS to use them in high-articulation situations.

Note that you should never use the rods + LLAMS together - you'll destroy an inner front CV in short order, and your wheel camber would be ridiculous. Plus there is a limit to how high the airbags can raise the car - if you have both the rods and LLAMS set at +20 or more, the compressor will quickly reach thermal cut-out trying to extend the bags to a non-existent height.

Cheers,

Gordon 2015 RRS SDV6 SE, Santorini Black, GOE 2-way HS rods, Traxide dual battery, 275/55R20 Nitto TerraGraplers

2015 Discovery 4 SDV6 HSE - GOE 3-way HS rods, GOE underbody plates and sliders, 275/65R18 Courgia MT

Hi Gordon

Thanks for the info and many thanks for the time on the phone yesterday.

Just to clarify for me (and for others who may be following this thread), the issue with running the Llams kit and shortened rods is that you can overextend the vehicle height and burn out the compressor.

This would happen when:
You have the vehicle in off-road mode (+50mm with shortened rods + 50mm offroad height = total of 100mm lift) and get into a position where the vehicle senses you cannot proceed and goes into extended mode automatically thereby trying to raise the vehicle past it's total maximum extension.

I'm not sure on the actuating sequence for extended mode but understood that it can only be accessed when already in off-road mode. That is, the vehicle will not automatically go into off-road height (and/or extended mode) if you put it on it's belly and the vehicle detects an obstacle.

If that is the case, my theory is that you cold run both the Llams and the shortened rods in the following way:

Leave the car in road mode at all times
Run the Llams setting at -20mm for on-road use (giving you a +30mm at all times)
Run the Llams in the off setting for general off-road use
Run the Llams at +30 or +50 manually as the terrain requires it.

Your explanation of the extended mode is not quite right.

There are two additional settings above off-road height: 'extended' (around 30mm over off-road) and 'emergency' (or 'super-extended', around 60mm over off-road). 'Extended' can be triggered only by the car (when it thinks it is grounded), and 'emergency' can only be selected (by the driver) once the car is in 'extended'. Therefore neither of these settings are available to the driver unless the car initially thinks it's grounded. But triggering of extended mode can occur whether you are in off-road, normal or access height.

There is no benefit to running with both the LLAMS and the rods. Simply selecting +50 on the LLAMS when in off-road height will place the car at around the old 'extended' height. This still leaves enough in the system for the car to react to grounding by pumping up to the old 'emergency' height. Obviously you cannot go any higher, so you wouldn't then try to select a new 'emergency' height.

Similarly with the shortened rods, you are 50mm above each calibrated setting, so in off-road you are now somewhere between the old 'extended' and 'emergency' heights. Still just enough left in case the car senses it is grounded.

Running with both doesn't give you any more height selection, nor does it allow the car to rise any higher. It will, in fact, cause the compressor to run longer and harder and thermally cut out. In other words, the combination of the LR height settings + LLAMS, or the LR settings + shortened rods, will give you the max height you can get from the EAS.

What you are proposing will fail if the car thinks it's grounded (which CAN happen in on-road height).

Cheers,

Gordon 2015 RRS SDV6 SE, Santorini Black, GOE 2-way HS rods, Traxide dual battery, 275/55R20 Nitto TerraGraplers

2015 Discovery 4 SDV6 HSE - GOE 3-way HS rods, GOE underbody plates and sliders, 275/65R18 Courgia MT

Thanks for clearing that up Gordon.

Was unsure as to how the engagement of extended mode was triggered.

This makes more sense to me now.

As for the 'fail' i was referring to the compressor failing if it tries to extend the suspension past maximum height possible.

From some of the US posts, I understand though that the Rods can come in handy in the event of a suspension fault whereby the vehicle lowers itself to the ground and you can't access the compressor. Would I be correct in assuming that installing the rods should give enough clearance to hopefully nurse the vehicle back to civilisation 'Black Betty' Java Black RRS 07 TDV6

Jimmy - ask Gordon about the new product to get around this issue that he is developing  07MY RRS TDV6
Arctic Frost
Aspen Interior

Jimmy Salsa wrote:

From some of the US posts, I understand though that the Rods can come in handy in the event of a suspension fault whereby the vehicle lowers itself to the ground and you can't access the compressor. Would I be correct in assuming that installing the rods should give enough clearance to hopefully nurse the vehicle back to civilisation

Gordon, JS, a question for a novice here, i have the standard 19' V Offroad Alloys on my TDv6 3 litre, what tyres with more off road bias would fit as standard without the need for any hacking of the liners or potential rubbing. Are there any that meet the load and speed ratings, as none of the tyre company websites or distributors suggest any do.

Thanks Another Pommie Bar Steward down under

MY20 Defender 110 SE P400 Eiger/Ebony
MY10 3.0 RRS TDv6 Fuji/Ebony/Anigre

Hey Zilch,

Hope Sydney is treating you well.

Most of the manufacturers tend to jump from 18 to 20 inch specs.

I think you would be better buying a cheap set of 20 inch steel rims and running something like the Cooper Zeon LTZ.

There have been some good write ups on them in mag testing recently and I've run the 18's through some very rough terrain without any problems. (vids below were all done on Zeon LTZ's)

http://youtu.be/BX5eLPOOe2k

http://youtu.be/Wmjm2mu_7fY

Unless you are going to be doing rougher off-road stuff than this you should be fine.

I only went to mud profile because we were tackling rougher tracks than this most weekends and the A/T's just clogged too quickly.

Cheers

JS
[/url] 'Black Betty' Java Black RRS 07 TDV6

If you're sticking to your 19" rims, you only have two options, the Pirelli ATR or the General Grabber AT. The latter is not available in Oz yet (2 to 3 weeks before the first shipment arrives) and the former can be pricey and difficult to locate. Both will meet the vehicle specs and provide better off-road/touring performance than the std road tyres.

Cheers,

Gordon 2015 RRS SDV6 SE, Santorini Black, GOE 2-way HS rods, Traxide dual battery, 275/55R20 Nitto TerraGraplers

2015 Discovery 4 SDV6 HSE - GOE 3-way HS rods, GOE underbody plates and sliders, 275/65R18 Courgia MT

Gordon, JS, thanks for the advise, i may wait for the GG's to arrive and see how quickly i can swap out the eagles

thanks Another Pommie Bar Steward down under

MY20 Defender 110 SE P400 Eiger/Ebony
MY10 3.0 RRS TDv6 Fuji/Ebony/Anigre

hi zilch

gordon forgot to mention the other option of the goodyear wrangler MTR in 255.55.19. This tyre will give a better result in offroad use but the other two he mentioned will be better for road / mild offroad use.

Best option is to have a set of each to suit various driving terrain. As it happens, I know of a set of 6 MTR's with 10-12mm of tread mounted on 19" Y-spoke alloys available for $1500....if you are interested.

regards.............frank my10D4se3Ltdv6 current
my08RRStdv8 sold
my07RRStdv8 sold

frank, main issue i have is that i have nowhere to store them, my house in Airlie is a holiday let, so no room there and i have an apartment in Sydney with no secure storage (apart from a vehicle space). Hence the reason why i am thinking of the tyre replacement route. I would love a set of the compomotives, but same problem  Another Pommie Bar Steward down under

MY20 Defender 110 SE P400 Eiger/Ebony
MY10 3.0 RRS TDv6 Fuji/Ebony/Anigre

I wonder how much helium is needed in each tyre to get them to float on the ceiling??? LOL my10D4se3Ltdv6 current
my08RRStdv8 sold
my07RRStdv8 sold

Hi Zilch,

Forgot to mention - I have a client with a set of near-new Pirelli ATR's + RRS rims (19") for sale. PM me if you're interested.

Cheers,

Gordon 2015 RRS SDV6 SE, Santorini Black, GOE 2-way HS rods, Traxide dual battery, 275/55R20 Nitto TerraGraplers

2015 Discovery 4 SDV6 HSE - GOE 3-way HS rods, GOE underbody plates and sliders, 275/65R18 Courgia MT