Correct Psi

Hi i have these tyres fitted on my 1987 defender 300tdi, what is the correct PSI please
MAXXIS WORM-DRIVE A/T
ALL TERRAIN, ALL SEASON TYRES
265 75 16
The fitter put in 30 psi all round
But back driver tyre wearing on outside, thank you

It would change with load carried and whether you’re off-road so pressures would be quite low
Has that fear tyre moved from front poor tracking wears tyres on edges

No they have only done 2500 miles no off road and loaded sometimes only

Dunno if this helps i run mine fornt/rear at 36 PSI when just using onroad.

have you done your tracking? sounds more like tracking issue.

He says it has been on the rear since new I think.
If it has been on the rear the whole time then there is an issue. Have you checked the pressure in that tyre recently? Wearing on the outer edge can be a sign of running at low pressure.

tottot said:

He says it has been on the rear since new I think.
If it has been on the rear the whole time then there is an issue. Have you checked the pressure in that tyre recently? Wearing on the outer edge can be a sign of running at low pressure.

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This is why im asking about pressure as ive read that on road can be up to 38, so thought someone may know

But have you checked the pressure now? 30 is a good compromise. If heavy loaded [and hairing around left hand roundabouts ] 38 but ride comfort would suffer. Is the other rear ok ?

Do you mean just one outer edge on the tyre or both?
If it's both then it's pressure, if one then it's geometry

tottot said:

But have you checked the pressure now? 30 is a good compromise. If heavy loaded [and hairing around left hand roundabouts ] 38 but ride comfort would suffer. Is the other rear ok ?

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Its 31 all way round, the other rear is wearing quicker than the front but not as bad as drivers side, don't hair anywhere not heavy loaded only occasionally

kermit_rr said:

Do you mean just one outer edge on the tyre or both?
If it's both then it's pressure, if one then it's geometry

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The drivers side is on outside worse, both tyres wearing quicker than front

if its tracking there isnt "adjustment" on the rear - will more likley be your stub axel is worn and the bearings are not running as they should so your Castor is out.

tyre pro or similar will do free tracking check's so you can rule this out.

shaynecm said:

if its tracking there isnt "adjustment" on the rear - will more likley be your stub axel is worn and the bearings are not running as they should so your Castor is out.

tyre pro or similar will do free tracking check's so you can rule this out.

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Camber. Bent axle or stub axle maybe. You will need to get it measured.

as mentione dyou cannot adjust the tracking on the rear so it si replacing damages parts, bearings, stub axles, bushes etc. If you are unsure if it si pressure or a tracking issue you could try the old fashioned chalk method. Rube a thick line of chalk across the tread in a couple of places and go for short a drive. The chalk will rub off on the centre if over inflated, the edges (leaving the centre) if under inflated, and just one edge if there is a tracking issue. if it rubs off evenly all is good OR your test drive was too long!

As every one has said there is no tracking adjustment on the rear axle. There is no camber, there is no trail, its a solid bar with a wheel on each end.
The axle pivots on the A frame which is attached to the chassis and allows it to flex like a see saw.
To stop it moving backwards and forwards there are two, fixed length, rear radius arms which are bushed at the axle end near the outer ends, and forwards to the middle(ish) ot the chassis.
These allow the axle to move vertically on an arc

If the A frame pivot wears it would allow some rotational movement fore and aft and you hear this as a loudish clunk when changing from accelleration to braking.
The radius arm bushes can also wear and this allows some lateral rotation which is also noticable, but less so than the A frame.
The rear wheels are driven by half shafts that sit in hub stubs, which support bearing mounted wheels.

There is no opportunity for the rear wheels to develop camber unless a wheel bearing has failed which is more self evident than a worn tyre...

I run 35 to 40psi on road with my D90 and 15 to 20 off-road.
Occasionally I forget to pump-up.
It makes little difference to my tyre wear of mpg to be honest, but I am only going shortish distances and never on dual-carriage ways or at motorway speeds.

As above with the tyre wear.
I run my 110 at 36 ish all round, but heavily loaded or towing up to about 48 at the back, though at max the book says 65.