Which tyre pressure for on-road?

[Nicool]

Hi guys,
with previous cars i’ve always followed the instructions on the plate inside the door when deciding on tyre pressure.
now that i own a 4wd (disco3) i got to purchase a new set of tyres (opted for HANKOOK 265/60R18) d and got a mobile installer to change them at home.
to my surprise, all 4 tyres were reading between 44 and 47 psi on my portable ARB gauge, and same thing at the local servo.
i went at the servo as i started doubting my ARB gauge, given that the plate on D3 gives me 33 psi front and 36 psi back (back increases to 42 if max load).
I’ve asked the installer who said they put 40psi in all 4 tyres, clearly i told him his gauge was probably off, but even so, why putting 40 psi instead of following Land rover recommendations for bitumen driving?

so i did lower the pressure to 33 & 36 psi, but now i am finding that my tyres look a bit bumpy, like fattish on the bottom.
so wondering if those specific tyres require extra pressure? I surely didn’t read so.

i did search aulro for answers but found mostly pressure advice for sand/mud driving, so hoping i could get advice with this new post.

cheers
Nico

[DiscoMick]

The placard is for original tyres, which were probably road biased. Heavier tyres may require higher pressures and bulge if too low. Experiment a bit. Tyre guys usually stick in 40.

[loanrangie]

Placarded pressures are a balance for comfort,stability and wear.
I run 38f and 40r which seems good for my mostly freeway commute.

[Tombie]

Placarded pressures are a balance for comfort,stability and wear.
I run 38f and 40r which seems good for my mostly freeway commute.

Good pressure choice. Rides nice and handles well at those pressures.

[DiscoMick]

My Defender is running 36 front and 48 rear on ATs, which seems to work well on the road. Defenders require much higher pressure at the rear than the front. Each vehicle is different.

[Eric SDV6SE]

MAXXIS 980AT's all round at 45psi cold, run at 48 hot on Highway driving. great mileage and a bit more road noise, but turn the radio up and all is good. Wear is nice and even, rotate every 5000km or including spare. I find 32-34 just too soft.

Off road adjust pressures to suit conditions of course.

[Nicool]

Thanks guys very helpful! I ll try 38/40

[DiscoMick]

Thanks guys very helpful! I ll try 38/40

Check if the placard recommends different pressures front to rear, then include that difference in the pressures you adopt.