I am in need for some gereral information concerning '95 thru '98 F250 diesels. Are the '95 thru '98 powerstroke engines basically the same as say '99 thru 2002? Were there engine modifications made in later years that would suggest I only consider these? Are all powerstroke diesel engines turbo charged? Sorry if I have asked a dumb question.

 

All the PSD are turboed, the last year of the non turbo was 93/early 94. FYI there is no such thing as a 98 F250HD or 350 (only 2 trucks that would have the PSD) since in 98 they were starting to produce the SD line but they were being badged as 99 models so there is a 1 year gap in the badging, but trucks were still being built then. The older 94.5-97 PSD used single shot injectors (except the 97 California edition PSD). This is thought by many people to offer more power than the later split shot design. The other downside is that the mileage isn't quite a good with the split shots but you're talking only a few mpg. Now I have looked alot at the 97 and the 99+ diesels for my next truck. The 94.5-97 are nice, but they're loud, much louder than their newer counterparts. In 99 the PSD was reworked some and was in its second generation. In 99 they got intercoolers, split shot injectors (these with the right chip can be converted to single shots like the older gen), larger HPOP (high pressure oil pump used to run the injectors) starting in the 99.5 SD, more clearance for downpipes, and an updated turbo and housing. There were also computer upgrades as well. Another thing is that in early production for the 01 model year Navistar switched to Powdered metal rods instead of the forged rods they had been using. This is fine for a stock truck, but once you start upping the HP then its much easier to break them. For me I was going to buy a 97 F350 PSD but after driving a 99 I decided to skip the 97 and look for a 99-early 01 truck (built before Nov 16 2000, though thats a rough estimate and it seems that the first engine to come out with PMRs was 1488312). To me the power and speed is much bette with the newer engines, as well as EGT control due to the intercooler. This IMO makes it a better platform than the older generation PSD. The older gen can be upgraded to roughly the same as the gen2 but its alot more expensive.