What does a bad/collapsed lifter sound like?

[Randee of the Redwoods]

I know what a dry lifter sounds like on a gas engine, I just don't know if it would sound different on a diesel seeing as how the ambient noises are different as well. I have a funny howl noise in there too while I'm at speed so you're guess is as good as mine on that one.
So far, so good. I'm 300 miles and counting since I bought the truck. Been driving it everyday to work. When the key switch won't engage the starter, my universal starter button setup will.

[rjschoolcraft]

I can't say that I've heard a collapsed lifter on a diesel, but I don't see how it could sound much different than on a gasser.

Your howling sound...I don't know, but...

Around 1993 or 1994, I overhauled a 6.2 in an 85 GMC 2wd 3/4 ton pick-up. He used the truck to tow utility trailers carrying Skid-steer loaders for his rental equipment business. He brought the truck to me because he thought it had blown head gaskets.

Long story short...I didn't drive the truck or hear it run much before pulling it into my garage. It was a mess inside. The engine had come from a junkyard and was installed by previous owner. Cylinders were pitted...it looked like it had been sitting with water in the cylinders. Also, four of the lifters had failed roller followers. The rollers had locked up, skidded and worn clear through. The needle roller bearings had all dumped into the pan and were in the oil pump pick up screen. The wear on the roller followers was so severe that at least .100 in lift was lost. The owner hadn't complained of any misfires or lack of power.

The point...I don't know what those skidding rollers would have sounded like, but I could imagine a howling sound. Don't mean to scare you, but I thought I would share that with you.

After overhaul, the owner was really impressed with its power and how it handled the skid steers. He said he liked it better than his 6.9 Ford diesel that he used for the same thing. After 30,000 miles, one of his employees over revved it and tagged a valve...ventilated the block. Sad.

[GARY PAGE]

My guess is the vacuum pump. If it sounds like bee bees a rolling or an exhaust leak that probably it.

[MartyB]

Having had a lifter in my 6.5 go out, it has a "pist" sound when firing in that cylinder. Mine was the #8, back passenger side.

Marty