Hi folks

I've just had a set of 275/45R20 Michelin Crossclimates fitted, I've not done too many miles yet but the feel so far is good. I previously had a mixed set of Michelin on the front and Continentals on the rear which I know a mixed set is never best, but these made the car twitch at any road surface change.
I regularly checked and set to the LR recommended pressures as per the door post sticker, 33psi front and 36psi rears for light/normal load but the centres were wearing slightly more (garage forecourt type inflator which came with calibration cert. and checked out good against another pencil type and digital guage), so recommended pressures were slightly high.

So with the 45 profile being higher than the standard 40 profile I'm thinking the pressure should be lower still, going by the usual theory of low profile tyre needing higher pressures (all to do with air volumes etc.).

Anybody having fitted 275/45R20's to the l320, wheat pressures do you run at run at for normal light load, and do you find the wear even (assuming correctly tracked etc.)? 13MY Range Rover Sport Autobiography SDV6 - mine
14MY Range Rover Evoque Dynamic SD4 Black Pack - wife's
99MY Defender 90 TD5, Soft Top Conversion - my toy, and bairns favourite

I use 35 front and 38 psi at the rear with cold tires. a 40 or 45 tire does not make any difference. Tire wear is very even. A good wheel alignment is pivotal though and make sure that your measurement (gauge) is sound.
33 en 36 is normally on the low side, which would rather show side wall wear RRS 3.0 SDV6 HSE Lux
RRS 3.0 TDV6 gone
LR 3 HSE V8 gone
DiscoveryII V8 Gone
Discovery 1 V8 Gone
Mustang Shelby
Alfa Guilia (classic)

Hi,
we used to use a calculation using the max load and max pressure that is stamped into the side of the tyre and from memory the weight of the car, this was when greenlaning with a loaded D2 running 235/85/16 tyres so well from standard

will try to find it but a search may prove fruit full? it then uses the Actual tyres your running and takes into account any mods you have done (or not)

 Porsche Cayenne 2022
gone Porsche Cayenne 2020
gone Corris Grey HSE Dynamic 2016
gone Ipanema HSE lux 2010
gone Rimini HSE 2005
!!

36 rear & 33 front are OK for the Pirelli All Season tyres as they have stiff sidewalls, however for your Michelins I would use as already suggested 38 rear & 35 front.

Dave 2010 3.6 TDV8 HSE (Gone)
2011 Discovery 4 Commercial SDV6 (Gone)
1980 OBLIC 4.0ltr Range Rover (went a long time ago)

Thanks folks,

This is quite the opposite thoughts to what I was expecting, especially since I'd already noted that the recommended 33/36psi was too high indicated by the centres wearing more than edges. If I were to go higher pressure for the same loading then the centre wear would only be worse. The continentals on the rear had the usual tread loss on the edges but those treads cannot be used in measurement as they were not cut to the same depth as the centre line treads (an often unknown law, measured treads must be the same as the deepest cut treads - I've discussed this with a police relative who didn't know this and admitted most of his colleagues also probably didn't, until I brought up the MOT tyre advice site as evidence ).
But that was different tyres which I hadn't considered, although they were Michelin and Continentals rather than Pirelli Scorpions. The profile, being only 5% of the width more than 40 isn't probably a lot but I thought it important when I was considering dropping the pressure anyway to try and even out the centre wear.

I might just set to standard and just monitor regularly to see how it's going. 13MY Range Rover Sport Autobiography SDV6 - mine
14MY Range Rover Evoque Dynamic SD4 Black Pack - wife's
99MY Defender 90 TD5, Soft Top Conversion - my toy, and bairns favourite

The truth is, the same pressure applies to tyres whatever the aspect ratio, it is pressure after all, not volume.

The pressure also helps the tyre retain its shape, reducing this will only lead the tyres to flex more, so increasing wear on the shoulders.

Continentals are famous for wearing out on the shoulders, even their truck tyres do this, so for yours to do this at the pressures you have been running them seems rather odd to me.


Dave 2010 3.6 TDV8 HSE (Gone)
2011 Discovery 4 Commercial SDV6 (Gone)
1980 OBLIC 4.0ltr Range Rover (went a long time ago)

Does the 36/33 setting apply the same for the TDV8 as it’s heavier? I’m sure mine is 38/36 at the moment on Pirelli all season, so may need to adjust them, it does feel a little harsh at times Lee
—————-
3.6 TDV8 2010 (facelift) HSE Stornaway Grey
3.0 TD6 2018 Discovery HSE Luxury Indus Silver Dynamic Packs 1 & 2 - Sold due to COVID budget cuts at home 😢
Mini Countryman 2.0 Cooper SD All4 - White, black wheels, black decals - Great little car and so much fun!

Always ran both my old TDV8 and 5.0L S/C at 33 front 36 rear with 45 profile Pirelli all season on both 20 & 21" rims, personally found ride and handling fine with no undue wear.

Cheers
Col

Lee

Yes to 36/33 for the TDV8, that's what I use, have no experience of the RRS with the V6.

Dave 2010 3.6 TDV8 HSE (Gone)
2011 Discovery 4 Commercial SDV6 (Gone)
1980 OBLIC 4.0ltr Range Rover (went a long time ago)

Excellent Thanks Dave and Col Lee
—————-
3.6 TDV8 2010 (facelift) HSE Stornaway Grey
3.0 TD6 2018 Discovery HSE Luxury Indus Silver Dynamic Packs 1 & 2 - Sold due to COVID budget cuts at home 😢
Mini Countryman 2.0 Cooper SD All4 - White, black wheels, black decals - Great little car and so much fun!

I use 40psi all round 255/55/20 :/ RRS TDV6 2010