That does not suprise me. I worked with a guy at GM that was let go about 2 years before I was. He had a Dakota with the 3.9V6 and a 318 Transmission. It had over 300,000 miles on it and the transmission. You should have seen the massive home made bumper and trailer set up that farmer had on this thing. The first 100,000 where put on it by the farmer he bought it off of. That farmer if I rember right used M1 10W30 and did some extended oil changes. I think he was useing some type of synthetic inthe transmission as well. When my co-worker bought it he went to dino oil and 3000 miles oil changes and OEM transmission fluid and filters every 50,000 miles. So I know these engines can do it. He neverhad any internal engine or transmission problems just alternators,starter's,water pumps,brakes etc.......I do know he drove about 50-60 miles each way to and from work and it was all HWY. I never saw the inside of the thing so I cannot comment on the insides.
I worked with another guy that bought a F250 off another co worker. The first owner put close to 200,000 miles on it and was an Amsoil Dealer and always used Amsoils products in it. It had a 351 in it. When my co -worker bought it off the other he too switched it over to dino and 3000 miles oil changes and OEM trany fluid and when I left GM he had about 385,000 on it and the transmissiona nd engine had never been toughed internaly just usualy things that are wear items! It still had the OEM tining chain and he was about to replace it!
625K is not a big deal for the engine. Itis a big deal for the transmission. Keep in mind though that it did need a need head so he probably serviced both heads with new guids and seals at the very least when installing a completly new head and new valvces on the one side.It does nto say if the mechanic changed the lifter at the time or the timing chain etc..........
Their is a lot of information that is missing but really I do not see it as that big of a deal when talking abut synthetics and remote filtration.The main reason we do not see more of this is because most people do not put miles onthat fast and most people do not own their vechiles for 10+ years either!She was putting 62,500 miles a year on this things the average American does what 12K to 15K a year?
