Not sure how to best word the title, but here's my issue.

A few weeks ago my 2010 Suburban LT 4x4 (VIN3) went in for a head gasket repair. When it came back it developed a wonderful lifter tick. Shop replaced the lifters on one side, yet the tick is still there. However after a few minutes of idling the noise would go away and truck ran like a top, until it was shut off and sat. Then same problem. They said they'd replace the lifters on the other side. So one day while driving (after letting it warm), I got off the interstate and oil pressure just went to near zero. Warning light came on. However, the motor wasn't ticking, or knocking or seemed to be in any bad shape otherwise. I only live about a mile away so I figured if no bad noise coming I can make it. Thought it'd just be a bad sending unit (I've had that before). Go out to start the next day, oil pressure is not at zero, but not where it usually is and of course the noise is bad. Take it to the shop (literally right down the street) and they drop the pan and there is oil sludge like you wouldn't believe. Pickup screen is caked in sludge, oil is as black as night. Supposedly the oil was changed after the head gasket was replaced. Total mileage driven between head gasket and this other issue is maybe 500 miles. The engine has never knocked, just ticked until warm. When they took the oil pan off they saw some metal shavings and the connecting bearings (I think that's right, semi-circle with a flange) does have some scoring on it. Not like deep scores, but definitely scored. They're saying I need a new motor. I don't totally disagree. Truck has 255K on it and runs non-stop up and down the interstate and state highways. I am religious about oil changes and maintenance and if it needs something it gets it right then.

My issue is a new motor ain't cheap and I'm not exceptionally keen on putting in a junk yard motor, either. My thought is this: Since it's only been ticking (and zero knocking), and the ticking goes away when the truck gets warm, in my mind it means that the oil is warming up and thinning out to get past the globs in the pick up screen/tube/oil pump. After it warms up the motor runs like a dream. Is it worth putting a new oil pump and pickup tube in (and replacing any bearings that are easily gotten to) or should I just bite the bullet and drop a motor in it? Their thoughts is I have a 50/50 chance on this. Either it works and will work for a long time, or won't at all.

 

I would say if there is no severe damage to the lifters or valves, don't replace the engine. only replace the parts you would need.

 

255k and metal. Put repair money of a tired motor into a new one if the rest of the truck is in good shape and rust free. Your motor is well beyond a junk yard motor. It's not just new bearings, crank has to be resurfaced for new bearings. Bearings do not get ''hurt'' without crank damage.
Pan sludge takes a lot of miles of neglect to form, no way in only 500 miles.

 

I doubt a new oil pump will resurrect a worn out motor. How long did it run with a bad head gasket? Obvious coolant in the oil??