:'(At 245,000 miles, the piston cooling tubes plugged, scuffing all the pistons. At the time, I was pulling about 7000 LBs, through the B.C. Rockies, at times in 5th gear, and about 2500RPM. My exhaust probe is post turbo, and temps were getting around the 1000* mark, but I'd done this many, many times before. I still had full power, good oil pressure, normal water temp, and no excessive highway noise. I didn't know there was anything wrong, until I pulled into the toll booth, and it was knocking terribly. #6 was the worst, and got progressively better as you went forward. My understanding is, the oil passage runs from back to front. I change oil faithfully at 7000kms(4300 miles). The oil sample came back normal, just metals from pistons and cylinder walls. I've gotten the shop to save me EVERYTHING, and I'll send the old filter and cooling tubes away to see if they can figure out what happened. But in the meantime, I was hoping somebody out there could give me some ideas, as to what might have caused this. so I can prevent this in the future. ???

 

No it wasn't a Fram. BUT, I was using the LF3349 Fleetguard, which I later found out was the wrong one for my truck. I'd been sold this one since day one, and about 145,000 miles later, realized it was the wrong one. I did as much checking as I could find, couldn't see a find a difference between the two, so figured, everything has been alright for 145,000, should be alright. 100,000 miles later, and I run into this problem. Now, you can call me an idiot if you want to(I already have!), but when the oil analysis came back clean, I'm still debating if that was the cause, although not out of mind, yet. At any rate, just looking for some ideas to look for, before they get it all back together. The block and crank have been dunk tanked, I'm going to assume the oil cooler too, but will check on that. The relief valve in the cooler will also get checked out.

 

Ya! That's the truth! This little episode is gonna set me back about 8 g's CAN :'(. But where does a guy stop? I want to get that many miles out of it again before I move to a different truck, so I want it fixed right. Basically gonna be getting a complete rebuild.

 

DEZLPWR: Ya, I pull RV's for a living, and I'm worried about the same thing. But, I still owe more than I could sell it for. By rights though, the Cummins was the last thing I expected to break, I kinda expected trans., or rearend , or something first. O-well, will get her back, and blast down the highway somemore!!