Tyre pressure for 1,500 mile road trip

[DeejUK]

Should I over-inflate the tyres on my '17 Model X 90D if I want to achieve longer ranges at the expense of comfort?

I've got to drive 1,500 miles back from Norway to the UK, and I'll be trying to waste as little energy as possible (I'll be on range mode, avoiding using heating/aircon if I can). Is it worth bumping up the pressure of the tyres? The sticker on the frame door says they should be at 42psi. I'd never have considered doing anything other than 42psi, were it not for tales of 3s and Ys getting delivered at increased pressures, which at least proves that its safe to do so.

Any thoughts or experience on the topic?

 

[Big Earl]

Should I over-inflate the tyres on my '17 Model X 90D if I want to achieve longer ranges at the expense of comfort?

I've got to drive 1,500 miles back from Norway to the UK, and I'll be trying to waste as little energy as possible (I'll be on range mode, avoiding using heating/aircon if I can). Is it worth bumping up the pressure of the tyres? The sticker on the frame door says they should be at 42psi. I'd never have considered doing anything other than 42psi, were it not for tales of 3s and Ys getting delivered at increased pressures, which at least proves that its safe to do so.

Any thoughts or experience on the topic?

45 is still safe. Once you start going much higher, the center of the tires will start wearing faster than the outsides.

The most impactful thing you can do to save energy is shave a few MPH off of your speed.

 

[Mr H]

The increased pressures of 3's and Y's doesn't show it's safe as they're not going down a motorway getting hot, just sat on a ship avoiding flat spots. Keep yours at 42 and slow down.

 

[SalisburySam]

On my 2018 Model 3 the door jamb sticker cites 45psi/310kpa as the manufacturer-suggested tire pressure. I’ve kept my tires at that pressure throughout the life of my car. Tire wear has been quite even on all four corners as well as across the surface of the treads. The downside is ride harshness supposedly higher than filling at lower pressures; I’ve never tested this as I’m happy with my tire wear and driveability. The Michelin OEM max cold pressure is 50psi/345kpa on my 18” tires.

 

[Big Dunc]

It is true that you will reduce rolling resistance by inflating the tyres rock hard. I used to take part in charity races which involved pushing cars rather than driving them and inflating tyres as high as you dared was all part of the game.
However, you will also have less grip available to you, and as others have said, the centre of the tyre will wear more than the outside edges, resulting in reduced tyre life. If it was me, I would stick to the recommended pressures, which are recommended for a reason.

 

[SalisburySam]

It is true that you will reduce rolling resistance by inflating the tyres rock hard. I used to take part in charity races which involved pushing cars rather than driving them and inflating tyres as high as you dared was all part of the game.
However, you will also have less grip available to you, and as others have said, the centre of the tyre will wear more than the outside edges, resulting in reduced tyre life. If it was me, I would stick to the recommended pressures, which are recommended for a reason.

Which I’ve done. As I mentioned, the manufacturer-recommended pressure on my car is 45psi. No center tread wear greater than outside on any of the four tires.

 

[gangzoom]

I've got to drive 1,500 miles back from Norway to the UK, and I'll be trying to waste as little energy as possible (I'll be on range mode, avoiding using heating/aircon if I can).

Don't you have free charging on the car? Not sure I would bother with any of that, just drive as fast as you can and charge when needed.

I was doing 100mph+ the Autobahn through Germany, but thanks to road works/traffic, my average speed was barely above 50mph, I don't think I ever got to a charger with less than 30%SOC even on the 75D.

 

[Adopado]

Don't forget that any quoted tyre pressure in manual or on stickers is "cold" i.e. before the car has started a trip. Though you may have 42psi at that point this allows room for the tyres to warm up as you drive at motorway speeds ... they'll go up to 45 and above naturally. If you start higher then obviously as they warm with driving they will go even higher still ... perhaps higher than you really want. As others have said, there's more to be gained by knocking off a couple of miles an hour from your speed if you are doing it to maximise range.