'97 stock d3500 12 valver cummins 248,000km, no leaks and no blue cloud following me.
_I have lost a gallon of oil twice now within 80km's with no evidence of where it is going. It first happened to me a week ago and then again today, I usually am just putting along country roads between 50-80km/h and have no oil usage. If I get on the highway like I did today it took about 80km's to use 4 litres, the whole front end was done not to long ago up at Marks and does not leak, I was constantly looking in the mirror and there wasn't a cloud following me. Got home pulled dipstick and way down, so I pulled the closest to the turbo intercooler hose off and it was dry in there, then pulled the fresh air off, is a little sooty but not oily, wiggled the turbine no excessive play in it. There is a film of oil on the bottom of the fuel tank from the crankcase vent, but it's not dripping off or anything. I pulled the rad cap and no oil floatin in there.
_Any internet diagnosis you can deliver?

hey been away a iitle bit last couple weeks, drew told me about this.

really odd for sure. cause thats alot of oil to be going somewhere. did it happen all of a sudden? or has been gradual?

maybe lost some rings or failed piston. so you might be burning some and pushing some out the vent......I'll have to think on that a bit. maybe add bad valve seals on top of that......

compression test, hydrometer to the crankcase vent

Oh one other thing check your oil feed line to the injection pump for leakage. actually check the injection pump itself too for a missing plug.

and while your there check your gear case and cover, maybe got bit by the killer dowel pin.

soooooo.........whad up wit dat now?

Well, seein that this truck already has me kinda unhappy at it, I haven't done anything yet, but next chance I get I'm going to get a compression test done. I need 2 trucks, I was going to get another truck, cuz the ol Ford is pretty tired, the seventhree gots 800k on her so it had to retire, die or head in for a makeover. Bein that I hear nothin but complaints from peeps with they newer trucks, and seein it wouldn't die. I resorted to the latter, tryin to stick a 169k 99 seventhree in, not exactly a straight swap. Not to mention a bit of a lift and a 60 in the front, when thats done then I fix the dodge. It's fukkin wierd tho, I did 250km's on my usual run this week mostly the 60-80km/h range, hitting 100km/h every now and then fer a bit, and no oil usage. ????