Sunday, Dec 01, 2013 at 11:39
gbc - Hard acceleration, coupled with regular bouts of high speed, is the ultimate
test of any engine. Driving them in that fashion, will find all the weak points in the design.
The durability of the Peugeot designs is pretty reasonable. Remember, Peugeot have a long history of durability, they won numerous Redex trials in the mid-1950's and shocked lots of people when they did.
Virtually no-one had heard of Peugeot before the Redex trials.
I've seen quite a number of Peugeot diesels with very high kms and still performing satisfactorily.
The problems come when the likes of Ford start playing with the design. I'll wager when they built the 5 cyl version of the 4 cyl, they kept the same oil pump - instead of increasing it in size.
Anyone who has had a Ford 7.3L Powerstroke V8 apart, and compared it to the supposedly identical Navistar 7.3L V8 gets a shock when they see the differences.
Navistar are truck builders, just like Isuzu, they don't take shortcuts.
Ford bean counters constantly go through every part in a design to see how they can make it cheaper. In many cases, castings or forgings are replaced by less-durable metal-stampings.
Small steel components are replaced by alloy castings. Bearings are eliminated in the likes of camshafts and the camshaft runs straight in the head metal.
All these things cheapen and weaken a good design, and make it unreliable and with a reduced life.
We used to see this with International Harvester products in the 1960's and 1970's. IH buggered up a lot of their good products by cheap-ar*se, money-saving changes to designs.
If a manufacturer has a good reliable product, they have to learn to leave it alone, because trying to save $5 on a component, will often cost them millions (and their reputation) when it starts to break regularly.
The problem is, as GBC says, one component breaking will nearly always lead to catastrophic destruction of a heap of other components.
FollowupID:
803466