Help Low oil Pressure Jackaroo 92 3.1TDI

Oil pressure is a good indication to how hard your engine is working. And how well it is cooling. Have got a VDO oil pressure gauge on my hilux and oil pressure always drops before the temp gauge moves. I would check out your cooling system. If this passes all tests fit an after market oil cooler.

Sparky - oil pressure is related to engine temprature you stated when you go down hill the engine temp drops but the oil pressure stays the same keep in mind when you go down a hill you have air to cool the water through the raditor and the oil takes longer to cool also when the oil gets hot it thins out and if you have excess clearance in you bearing thoughout the motor you will not have any resistance to the oil therefore the oil will flow quicker through the bearing being thinner due to it being hot. check to see if the oil is correct for that engine - this is a reference taken out of a manual If the oil pump or relief valve are faulty. low pressure will be indicated with the engine both hot and cold. However, if the bearings are at fault a fairly high oil pressure will be indicated when the engine is cold but a marked fall in pressure will be noted when the engine is hot. I would first try changing the oil then if that does not work I would check to make sure that the oil is being cooled successfully if that fails I would try having the oil pump reconditioned I hope that is of some help

Regards Geoff

Sparky.
You dont mention how many ks the jack has done. if it is more than 200k the motor is probably a bit worn, but still ok, if you use a multigrade oil it will be good for many more ks. If the pressure drop bothers you drop the sump and fit a new set of bearings, the bearings should be under $100,from a engine parts specialist. Cheaper than the other options.
Eric.