2008 Toyota Prado Pricing and Specs

Toyota did have a spate of diesel engine failures some years ago when it was discovered that the fuel injector seals were leaking and letting fuel into the oil stream.

Sludge would build up on the oil pickup and eventually it be blocked and the engine would lose oil pressure. As you say the pickup can be inspected through the oil drain hole, so you should be able to see if there is a problem there. It is worthwhile changing the injector seals every 45,000 km.

It sounds as if it has been running lean for some reason, and the obvious place to start is with the injectors. You say the dealer checked them and they were found to be ok, so the next step should be to go through the fuel system, the pump and the filters looking for something that has affected the fuel flow. I doubt that it is caused by dirty fuel as you have been told. While you are checking inspect the oil pickup in the sump as there have been problems with fuel leaking into the oil past the injector seals causing deposits to build up in the oil and eventually blocking the oil pickup. It's a long shot because it usually happens at very high kilometres, not 100,000km like yours, but it's worth eliminating as a cause.

There have been a few issues with the tow bar on Prados and Toyota has been checking and replacing the attaching bolts and replacing the hitch with a genuine Toyota one where the vehicle is fitted with an aftermarket one. The Toyota hitches are rated to handle the weight the Prado is approved to tow.