"I have owned my 2004 Lariat w/ the 6.0L Deisel since new and love it. I only had a few minor issues under warranty at about 10K, but Ford took care of them. I haul a 35ft Toy Haulr loaded with Quads & bikes and this thing pulls like a champ. I have 81K and have it serviced with Mobil Delvac synthetic every 6K miles with no motor issues at all. Tranny has been rock solid as well. The only minor complaint is intermittent door rattles that come and go like a ghost - can never track them down nor could the dealer. Other than that, it's a workhorse."
"The 6.0 turbo diesel is unreliable, I bouught it new and have been meticulous about care and service intervals.
I was towing a two horse trailer (with horses( and it the engine cut out as I was making a turn. Braking and turning is difficult when you have no engine power. Then I read on the internet that this engine was known to cut out with no warning.HMMMM...seems that could be dangerous, why was there no recall? At the same time it when it would cut out with no warning it would surge forward 8 to 10 feet, at a stop light even with my foot heavy on the brake. It has been in the shop more than 30 days at one time. Until now I have been a loyal Ford fan. I have heard that some owners love this truck and it is never in the shop, and then there are people like me that find it always in the shop and unreliable."
"this has to have been the worst diesel i have ever owned , i have had 7 all from ford and the 6.0 is trash i recomend that ford carries on wit the 7.3 which was in my former truck which i had for 8 years and had 341000 miles on it , this motor has been junk from the start i have replaced the turbo's twice the injectors twice the motor has had to have been rebuilt 2 times in only 80000 miles this is my second trany from new and today i pulled out in front of a lady kicked it down and i felt it slip , come on i am a ford man till the end but this was one thing gone bad"