Following what I saw as comment on the subject:
new-transport / still-tax-the-diesel-t12328-60.html
and here:
new-transport / still-tax-the-diesel-t12328-70.html
the unleaded gasoline containing too much aggressive chemical eats all the seal of the engine: that makes that the old engine always turn but fleeing oil everywhere ... and in general it is necessary a complete disassembly too expensive to put them back in state
we need a new engine design with less weak point of sealing, with better accessibility of everything that needs to be changed to make it last
The cars that will make 400 000 km no longer exist on current production lines ...
There are metallizing additives that stop engine wear (anti-friction) and contain seal regenerators, I have been using them for over 20 years on my engines from the small mower engine to the car engine, this additive is remetalising, that is to say that it seals micro cracks in the metal and also contains a gasket regenerator which over time becomes too dry and creates leaks and can stop a leak that has already started, I have used this product as much on new cars than on used ones with high mileage, I have fun to name these products after so many years "of the mechanics in bottle".
I use Wynn's products and this is to advertise but to share my positive experience with their products that could bring your worn-down tacot engines back to a state closer to their youth.
An 350 000 kms engine traveled in town for example gargled with this product was in new condition even at this mileage, no wear and no leakage even the crankshaft seal having been replaced, another 200 000 kms car purchased used bouffant of the oil totally stopped consuming after 2 oil changes with this additive and turned like new.
A stretched oil change at 35 000 kms demonstrates less wear and tear by the transparency of the oil than an ordinary 6000 kms oil.
As I do not know if moderation allows me to advertise, I do not put a link but if you're interested I can do it in MP!
If it's not econological to keep your old crate for a few euros ...