Mud terrain success!!!! 285/50 R20

[Wheelan]

Hi all. As with most others, Discos and tyres have been doing my head in for years. Last Disco tried the GOE wheels with and AT Toyo 2 285/60/18, ok but not as aggressive as I would have liked for a second set of wheels. And on that, the range of 18 inch aggressive, high load tyres that will fit is limited to the BFG.
Current Disco (2015 HSE)has 20s, and while I wasn't happy that it was coming with 20s when purchasing the car, after some research came across a heap of versatile tyres in 265/50/20 and 285/50/20 which several have fitted with great success. When I came across the Atturo in the 285 size with a load rating of 119 I thought I would give them a go. So do they fit?? Yes with success. Dropped it to the bump stops and had only minor rubbing in the right rear front liner, which as you will see from the photos will cause no harm. Everything above this height was clear.
SO, now you can have your second set of mud wheels, with legal wheels, legal size, great load rating for cheap. BTW picked the set of RRS 20 x 9.5 53 offset for $400 on ebay and the tyres were $290 each fitted!! I know everyone that has spent the $$$ on the 18s will say "my sidewall is bigger, and will have a bigger footprint", and yes you are correct, but for the most of us that just want a solid set of aggressive tyres, this ticks the box, and so what if I ding the rims up a bit, I bought them scratched anyway.

And before you ask......yes they are noisier than the standard tyres!!!.....funny that!

See link for pics Shared album - Paul Maguire - Google Photos (https://photos.app.goo.gl/EFpMU9sTdjTVHhto1) note I removed the rear liner and refitted wheel for clearance pics

[Tombie]

Hello and excellent report...

Sorry to sadden you though... those wheels aren’t load rated to the Disco.... you can’t run RRS wheels on a D4...

If you are going to run that size tyre the HydroBushes and sidewall flex will likely see them rubbing everywhere from your photos... so continue to observe....

And you will need an emergency EAS kit - otherwise when it drops you will be stuck hard.

[Graeme]

The taller rear bump-stops from MY12 on-wards stop most over-size tyres from wreaking the havoc they do on earlier D4s when air is lost.

[Crofty]

The taller rear bump-stops from MY12 on-wards stop most over-size tyres from wreaking the havoc they do on earlier D4s when air is lost.

That’s interesting Graeme, I’ve been too chicken to drop mine to bump stops as a test. MY15 with 265/65/R18 Cooper STMaxx’s.

[Wheelan]

Thanks for the constructive criticism Tombie. Was not aware of the load ratings of the RRS though compared to the D4. SO from what I could tell gross vehicle axle load at the rear is 1855kg for a D4, which would make the wheels I have (900KG) just short. YOu know what, I can live with that. These wheels will prob be on the car 3 times max per year for weekend jaunts to the high country, and never at GVM. Yes not entirely legal....... .
The photos are the car [B]on the bump stops (via the Gap tool) and I drove it on the bump stops to see where it was rubbing, which was the liner in the rear, slightly.Yes you will get a bit of flex from the bushes, sidewall but I can live with this. As I said those pics were at full articulation. As discussed I did run the 285/60 R18 at 799mm and now running the 285/50R20 at 793mm, so slightly smaller. I never really had a drama with the larger tyre, some paint missing on the chassis rails and some scuff marks on the liner.

[Owen]

I have been looking at the 18's as an option for the D4 but after Fraser Island, may go up to 20's. Reason? Well the sand that was stirred up when driving in ruts sat inside the rims and chewed the brakes out super fast.

Had a super loud horrible sound one from the front when driving to lake Mackenzie one day. Nursed it back to camp and had a mate bring some new pads over and did a swap on the island.

On inspection, the sand sitting in the brakes had got in, got hot and turned to glass inside the inner pads on both sides .

Hence I am thinking a 20 inch rim may give better free space for crap to fall out when driving.

I did 9500 Kms for the trip, up to the Cape and back via Fraser Island and have to say I have come away surprisingly impressed with the Hankooks. Kids asked me best part of the trip.....Not getting any punctures was one.

Will keep my eyes out for a nice black set of D4 rims

[Wheelan]

That’s interesting Graeme, I’ve been too chicken to drop mine to bump stops as a test. MY15 with 265/65/R18 Cooper STMaxx’s.
You may surprise yourself, I actually heated up the liner at the rear, folded a towel 4 times and placed it on top of the tyre where is was touching then dropped it down to the stops to press the liner in place. This was not exactly successful though as it split the liner! Will replace it when selling.

[Graeme]

That’s interesting Graeme, I’ve been too chicken to drop mine to bump stops as a test. MY15 with 265/65/R18 Cooper STMaxx’s.
This was discovered after having fitted new MY12 shocks to my MY10.

[Russrobe]

Thanks for the constructive criticism Tombie. Was not aware of the load ratings of the RRS though compared to the D4. SO from what I could tell gross vehicle axle load at the rear is 1855kg for a D4, which would make the wheels I have (900KG) just short. YOu know what, I can live with that. These wheels will prob be on the car 3 times max per year for weekend jaunts to the high country, and never at GVM. Yes not entirely legal....... .
The photos are the car [B]on the bump stops (via the Gap tool) and I drove it on the bump stops to see where it was rubbing, which was the liner in the rear, slightly.Yes you will get a bit of flex from the bushes, sidewall but I can live with this. As I said those pics were at full articulation. As discussed I did run the 285/60 R18 at 799mm and now running the 285/50R20 at 793mm, so slightly smaller. I never really had a drama with the larger tyre, some paint missing on the chassis rails and some scuff marks on the liner.

FYI, I checked my wheel aligned report after noticing some scuffing on the chassis horn too (right side was rubbing not left), I stayed within the manufacturers specs and increased the castor (moved wheel forward), have never had a problem since. I now have zero rubbing up front with the 285 60 18s and only that spot at the rear where that tab is behind the guard that I was too lazy to bend back[bighmmm]. Obvs need to have a wheel alignment machine to do this so not a diy job, but can be requested. . .

A lot of the techs won't adjust your castor to precisely where it needs to be as it doesn't affect tyre wear by being out a little bit and still within tolerance. Only problem is now the chassis horns turned orange from the lack of frequent polishing it was getting[bigrolf].

[Wheelan]

Only problem is now the chassis horns turned orange from the lack of frequent polishing it was getting[bigrolf].
Bit of WD a day keeps the orange away!! That is funny. You running the 285/60s full time?

[Tombie]

So does a 1 second hit with some Rustguard [emoji41]

[Turtle60]

So does a 1 second hit with some Rustguard [emoji41]

As a new (to me) 2014 discovery owner of 4 weeks I just love this thing. However with already a week on Fraser Island I am a little let down by the tyres. I am pleased that some light truck rated tyres are possible. Well done Wheelan. While I have general grabbers that look and drive well, they are, at the end they day a 111 load rated tyre ( 1090kg) that offers little in sidewall protection. The Atturo as mentioned are 119 rated (1360 kg) and has three ply rated LT sidewall.
To put some maths to this if one was to load your Discovery to the 1855 kg rear axle rating then at 40 psi the GG’s ( or ANY current 19” tyres on offer) can carry 2180kg which means these non Lt rated tyres are working (carrying) at 85% capacity. Under the same conditions the Arturo is working a mere 66% capacity and could no doubt handle a decent lower pressure. The GG’s at 27psi we’re significantly deflated looking and would, in my opinion, be at significant risk outback. I am sure many of you fellow Landy lovers will have an opinion. I get the rim load rating issue and will look out for some 20inch rims which I think would be legal provided you DONT load over their combined rating which may be some 100 kg under the axle load rating.
Hopefully by mid next year Atturo or someone may develop an AT variant.

Wheelan a question for you is the noise “acceptable” and do u run a 5th 20” 285 spare under the rear. And also what did u do with you GOE rims?

I will post my mods soon but already have dual battery, three plug socket in rear, icom radio, rock sliders, snorkel and in prep for Fraser removed the very seats and fitted a fridge slide above a false floor. Get storage there.

[chuck]

That’s interesting Graeme, I’ve been too chicken to drop mine to bump stops as a test. MY15 with 265/65/R18 Cooper STMaxx’s.

Graeme

Does that mean fitting 275 55 20 BFG KO2's would not be too problematic on a MY16 D4.

They are 47mm increased diameter so should still be legal.

Cheers

[Tombie]

Do NOT run rims below the axle rating... remember, you’re not always sitting on both sides of the axle! So you want a decent rating to take those shock loads - there’s a factor built in that needs to be maintained!

There’s every potential your full 1800+kg load will be sitting on one corner quite regularly.

[Graeme]

Does that mean fitting 275 55 20 BFG KO2's would not be too problematic on a MY16 D4.

I understand that several people are running this size on their later D4, including at least one person who imported 275/55R20 Duratracs for his D4.

I'm interested in options in this size as my KO2s are too noisy for me on my L322.

[Wheelan]

[QUOTE

Wheelan a question for you is the noise “acceptable” and do u run a 5th 20” 285 spare under the rear. And also what did u do with you GOE rims?

I will post my mods soon but already have dual battery, three plug socket in rear, icom radio, rock sliders, snorkel and in prep for Fraser removed the very seats and fitted a fridge slide above a false floor. Get storage there.[/QUOTE]

Sorry for the delayed response. Sold the GOE rims 2 years ago, I do run a 5th, will load on the roof for those trips away and just keep the original spare underneath. One thing that used to **** me off with the GOE wheels was fitting that spare with the 285/60/18 on. Its definitely doable, just a PITA. I dont do enough trips away now, and I pack light so no probs keeping wheel on roof.