It wasn't just the 1990 & '91s, we had MASSIVE failures in the early '90s with the E4ODs, to the point that the company bought 100K mile extended warranties on them. Unfortunately, the Ford extended warranty didn't cover commercial use, so they got screwed & had to pay $3500-4000 to rebuild them anyway!! We had a cutaway '93 E-350 with a 14 foot box & liftgate that had the transmission rebuilt THREE TIMES! It was only when they swapped trannys with my '94 E-250 (that they were selling) that had all the updates done & put on a huge external cooler that the problems finally stopped. Ford engineers (hampered by their idjit bean counter superiors) are some of God's special people...