Each motor is different and "new" engine designs tend to have teething problems. Ford 6.0 diesel, Toyota 3.0, Subaru 4 cyls, Ford SOHC 4.0, and the list could go on and on. These are all examples of manufacturers changing proven components or complete designs that resulted in seriously damaging their reliability reputations. Most have made efforts to remedy the weaklinks or scrapped the design altogether, while others have just left consumers to their own diligence when it comes to researching before buying. The problem is when a new design debuts there isn't any information to research!
Personally I no longer buy new vehicles, but when I did I NEVER bought a new car during a major component's first couple of years on the market. With the price of vehicles these days I'd expect 300K miles out of every one of them. But check out the Toyota and Subaru headgasket issues. Both of these manufacturers were synonymous with reliability, and still are ---until about the 100-130K mile mark! I won't even get going on the Ford 6.0 diesel fiasco.
I love the new 4 door Wrangler, but IMHO they are sacrificing engine reliability in an ever increasing search for MPGs and HP (the same goes for making every vehicle as "luxurious" as possible). I mean folks are having to sleeve their axle tubes because they are so lightweight. But they've got side airbags, 400w stereos, 8 miles of wiring for all the electronic "aids", power seats, power windows, enough hoses underhood so you can't see the engine, etc, etc. How many of us are such piss poor drivers that we need auto headlights, wipers, HUD readout, information center (computer) in console, heated/cooled cupholders, and all the other gobbledygook in our 4x4s.? They can still offer a nanny-state version for the soccer moms and teenage graduation present recipients who buy insurance intending to crash on a regular basis because they can't be bothered to concentrate on driving.
Build an LJ size Jeep with a Kubota 3.3L mech turbodiesel, AX-15 trans, 44 axles with lockout hubs up front, PS, PB, comfortable seats with adjustable bolstering and lumbar, opt A/C, opt 25-30 gallon fuel tanks, and a CJ-ish plain interior and it should sell like hotcakes. Reliability, longevity, durability, EASY minimal maintenance, simplicity of pull the floor covering and hose out the crud and unheard of economy in a modern Jeep (not counting the CRD Liberty and G. Cherokee) all for one of the lowest prices of a new vehicle offered in this country. NO R&D needed. All components are readily available and proven performers - AND what Jeepers have been begging to have available for decades.
Whew! Sunday Soapbox rant over:coffeedrink: