Attention: TDR Forum Junkies 
I'm wondering if something is dying on my truck.
After prolonged driving times of about 4 hours constant driving without any engine shut down the problem occurs. This is the second time I have noticed it. Usually the trucks comp says 23mpg at 63mph cruising basically unloaded. egts run about 650. Then I notice its getting about 14mpg, egts climb to about 900 and it sounds like its working harder, like climbing a steep grade. Even going down hill it will only hit like 19mpg. I knock it out of gear and let it idle down to curb idle and if that doesn't make it go away I rev it up to about 3000 and then it goes away.
I haven't noticed if it does it at once or over the course of a few minutes goes from good to bad.
Almost seems like 1 or 2 holes have stopped firing. But it only sounds like an added load from climbing a hill.
After prolonged driving times of about 4 hours constant driving without any engine shut down the problem occurs. This is the second time I have noticed it. Usually the trucks comp says 23mpg at 63mph cruising basically unloaded. egts run about 650. Then I notice its getting about 14mpg, egts climb to about 900 and it sounds like its working harder, like climbing a steep grade. Even going down hill it will only hit like 19mpg. I knock it out of gear and let it idle down to curb idle and if that doesn't make it go away I rev it up to about 3000 and then it goes away.
I haven't noticed if it does it at once or over the course of a few minutes goes from good to bad.
Almost seems like 1 or 2 holes have stopped firing. But it only sounds like an added load from climbing a hill.
