Now that’s going deep! 2009 pre-facelift 3.6 TDV8.

If you want to play then the way to check tyre pressures for one off builds, different size tyres etc, is the following...

Guess a baseline PSI, pump all tyres to this when the tyres are cold, best left overnight to ensure they are cold...

Then drive at least 20mins down a motorway at 70mph, pull off and as soon as possible check the pressures...

The pressure should be 4 psi higher than cold...

Adjust the starting temp and try again the next day until you get the 4psi spot on....

Job done...

Yes there are some variables but apparently it works...  Pete

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2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
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Not sure I have the time for that game but good to know! 2009 pre-facelift 3.6 TDV8.

As someone in Canada, I've always been curious about the recommended tire pressures in North American versus Europe.

In North America, the only recommended tire pressure is 36psi front and 42 psi rear. There is no normal load and heavy/full load. It's just one recommendation.

Meanwhile in Europe, you have a recommended pressure for a regular load up to 4 people and then a higher pressure for 5 people + luggage.

I've heard that it's because North Americans are heavier and tend to tow more but does anyone have any insight on the truth to that? I'm genuinely curious why it'd be any different in North America.

For the record, I've used both 33psi front, 36psi rear as well as 36psi front, 42psi rear and it's usually just 1 or 2 people in the vehicle and no luggage or towing. I don't notice much of a fuel economy difference but the ride is definitely softer and smoother on the lower pressure. 2010 RR SC
2007 RR SC

Interesting. Can you imagine the meeting at JLR when they said - You know, we only need one recommendation on the North American sticker *taps belly*…

I am finding 33psi front & 36psi rear fine but would not want to go harder under normal load. Have found that my tyres (scorpion zero, 19”) despite being new-ish don’t hold their pressure as long as I would expect. Is that a Range Rover trait due to the sheer weight?

Will keep checking each month to monitor. 2009 pre-facelift 3.6 TDV8.

I think the NA spec. tyre pressures is due to their peculiar legislation where everything has to be maximum rated all of the time, expecting your average leftpondian to change tyre pressures dependent upon load would probably trigger some sort of class action claim for excessive bending over or queueing at the tyre inflator station....

KitTheRam wrote:

Interesting. Can you imagine the meeting at JLR when they said - You know, we only need one recommendation on the North American sticker *taps belly*…

I am finding 33psi front & 36psi rear fine but would not want to go harder under normal load. Have found that my tyres (scorpion zero, 19”) despite being new-ish don’t hold their pressure as long as I would expect. Is that a Range Rover trait due to the sheer weight?

Will keep checking each month to monitor.

Yes. Just, so far out of the various cars I currently own non loose psi like the RR thus far. 2009 pre-facelift 3.6 TDV8.

Mine don’t loose pressure so maybe worth getting them refitted. 2012 TDV8 Vogue (L322)

Ok thanks. Good to know. 2009 pre-facelift 3.6 TDV8.

So it turns out my £40 Michelin digital air pump has quite an accurate psi measurement as it’s basically the same reading as my new manual draper pressure gauge. Also find I let out a lot of air using the latter, perhaps need to use it more to get the hang of it but not great.

A question I had came from the fact that I needed to turn on the ignition to get power from the 12v socket to start my pump up (both front and back sockets), I thought they maybe permanently live as I believe they are in older L322’s. I was thinking of leaving a belkin usb socket plugged in the glove box at all times if a live feed is ignition based on my car. 2009 pre-facelift 3.6 TDV8.

All tyres lose pressure as rubber is porous to some components of air (hence the fad for nitrogen inflated tyres a few years ago), it's possible that your alloy wheels are corroding and also becoming porous. In the absence of being able to put your wheels in the bath to check for leaks (always leak check with the tyres inflated to their safe maximum) use a soapy spray, not forgetting to check the wheels & valves, not just the tyres and rims.

Also be aware of checking tyre pressures in roughly the same conditions each time, checking them on a hot day or soon after a drive will read artificially high, checking them on days like today (just above freezing) will cause them to read low. I check mine once a month with a calibrated gauge (it's only calibrated because work insist on it, I'm not OCD about it!) and I generally have to put 7-10 kPa in each tyre which is about the same as every LR and other car I've owned.

Thanks. Yes I try to check them once a month when cold but not too cold. 2009 pre-facelift 3.6 TDV8.

You should really be checking pressures every week and visually checking them (for excessive pressure loss) before every trip. 2012 TDV8 Vogue (L322)