This has been a very tough communication to debate on who is to blame here and the problems. Here are the REAL facts and stories from Ford. Before 2007, there was the 3.0L V6 Duratec. This was the most powerful and last Ford FWD transverse-engine with external belt-driven water pump, and it was last installed in 2012 Fusion and Escape. This engine had won numerous awards on reliability, and during 2007-2009, Ford Fusion V6 was ALWAYS rated more-reliable than Toyota Camry and Honda Accord by Consumer Reports, which shocked the auto industry at one time. Consumer Reports praised Ford as the only Detroit automaker with "world-class reliability" that almost all vehicles (thanks to the Duratec engines) were just as reliable as any Toyota and Honda vehicles.
Consumer Reports 2009 Annual Car Reliability Survey – Who’s up and who’s down
Then 3.5L came out in 2007 to replace 3.0L for more power, and 3.7L in 2008 to replace old 4.2L OHV. Both were based on 3.0L's engine-block design. These new engines were jointly-designed with Mazda together in Japan.
I'm not sure at all and still investigating, but the internal water pump design (which later ends up disastrous) could be a Japanese-design from Mazda. Mazda was the first to release 3.5L in 2007 CX-9 on March 2006 launch-date, five months earlier than Ford. Same internal water pump design, could be Japanese.
Mazda of Japan believed that if Ford can find and install a lifetime-warranty internal water pump driven by timing chain, these new Duratec V6s are technically bulletproof and reliable for up to 300,000 miles (as well as up to 1,000,000 quality-testing miles with original water pump). Unfortunately, Ford failed to comply Mazda's Japan technical requirements, skimped on parts quality, and then the water pumps failed as low as 50,000 miles. The Mazda CX-9s built in Japan with same 3.7L engine lasted a little longer for up to 200,000 miles. I do understand that internal water pump is never a smart idea since it's a wear and tear part, and maybe the Japanese engineers at Mazda headquarter regretted later on. But Mazda Japan prefers to blame on Ford instead for skimping on parts quality.
Despite all the negative reviews you read, these Ford Duratec V6 engines do have an excellent reputation on reliability if designed everything correctly from scratch. When they run, Consumer Reports still rates Ford Duratec V6s more-reliable than General Motor's High Feature V6 and Chrysler's Pentastar V6 (see Engine Major, nearly all straight green dots very close to Toyota) in latest April 2018 magazine, assuming the original water pump hasn't failed yet. Either Ford or Mazda (I don't know who to blame) accidentally missed one part of design here that screwed us all up. I'll let you debate...
If Ford sticks only to Duratec engines (and Ecoboost turbos don't exist yet), and all use belt-driven water pumps, Ford's original-root from 2008 being Detroit's most-reliable automaker still exists 10 years later today in some areas (Ford Fusion & Escape w/ 2.5L).