Very low oil pressure when hot - a worry?

Hi

I have a willy 3 with around 105k miles on the clock. Now, when the engine is cold the oil pressure is circa 4 bar on idle rising to 5.5 - 6. I was stuck in traffic for about 30 minutes after a drive (not a particularly spirited one!) and the oil pressure gradually fell off the scale. Its still high when cold so I don't think there is a pressure probem per se but obviously when its hot its very very low.

I looked at the oil when it was hot and it was so thin - almost like water. I assume the oil needs to be a bit thicker but not sure what to put in. Does anyone know of a thicker oil that is used and if so what is it? has anyone else had this porblem?

Thanks

Ben

dash gauges are usually crap, they get worse with age

correct oil is 15w-40 semi synth

and if it hasnt blown up yet, its probably okay ;-) if your genuinely worried, get a mechanical test guage on it and check the pressures properly :-)

If there is no oil pressure light coming on it's all good.
Oem dials are really crap, senders too tbh.

Has anyone got any experiance of after market gauges??

Get VDO one. They are very good.