Hey guys, I have a problem with a 5.3 Vortec in a 2000 K1500 Silverado. (61000 miles)

I was told everything was fine with the truck, driving down the road, then all of a sudden, without warning, it just lost all oil pressure.
I was also told that it was stopped "immediately" after seeing the warning light come on and the gauge reading zero.
I started it for a few seconds, and yes, no oil pressure.

It's hammered.

It sounds like it's ready to spin a bearing, (if it hasn't already) and has the expected valvetrain noises too.
Oil level is a little high on the dipstick, looks clean, and it has an AC Delco filter on it.
Before I tear into it, has anybody else heard of such a sudden failure with the 5.3?
If it was an older small or big block, I'd have a clue, but I know nothing about these other than what I've heard about the piston slap issues that have been reported.

Thanks.

Oil pump drive is lost. Keep us informed.

Don,
Have not heard of very many problems with those engines. I found no bulletins having to do with oil pressure in my AERA www.aera.org (http://www.aera.org) software. I wonder if you are getting the entire story ?? If the oil looks "too" clean, you have to wonder if it was run empty and then filled up after the fact. If you need any technical info on the engine, let me know.

Everett, yeah, that was the first thing that crossed my mind too, we'll see.

Bill, the oil does look suspiciously clean. There are no obvious leaks.

I'm going to get some more info and get to the bottom of this. As you know, some people are reluctant to admit mistakes.

Thank you both.

Edit:
I just talked to the guy that was driving it when it happened. He is the owner of a lot that is one of our major accounts, and I trust him.

He bought the truck from another dealer, that just had the truck serviced, and was "ready" for sale. He drove it for 4 miles...and said he heard "lifter noise", but it carried 40 lbs of oil pressure...then boom.....suddenly had zero.

He drove it about a block and a half in that condition.

Bill, if you could refer me to some tech info, it would be greatly appreciated. I don't even know how the oil pump gets driven. :rolleyes:

[ 02-10-2005, 09:58 AM: Message edited by: ZZ430DropTop67RS ]

I believe the oil pump is driven by a "distributor plug" in the normal old school configuration of SBC design. Correct me if I'm wrong.

For what it's worth...

I know that 1999-2000 F-body LS1's have been known to have oil pump failures (which is why 2001-2002 F-bods have a revised oil pump IIRC) and maybe it has something to do with that.

Just a WAG.

Thanks, I'll check the LS1 boards.

ZZ-

Here's what I found:

http://www.ls1tech.com/forums/archive/index.php/t-154396.html

WildBillyT, that's exactly the way this one happened, just driving down the road.

I see that even very low mileage motors have had the pump fail.

Of course the 5.3 uses an iron block, but many of the LS1 parts interchange. (I'm on a steep learning curve here)

I really thank you for the info.

Don,
The oil pump is in the front of the engine, driven by the crankshaft like most Japanese engines have been for years. If you are planning to get into the engine, get a factory service manual. It is much more precise and complicated compared to the old V-8s. Most of the bolts use the torque angle method of tightening an most bolts cannot be reused. The main bolt torque sequence is about a 50 step deal ! Head bolts must be replaced for wsure, along with the "side" main bolts. You have to follow the torque specs and procedures exactly or the crank will lock up. Even though it only has 60 k miles, yo may be better off in the long run with a factory reman or new engine. If he just bought the truck from a dealer, I would think it should be under some sort of warranty, unless it was sold "as is".

Thanks Bill.

Maybe I will just plug in a new motor and call it good. I've always been trained to repair if possible, but it sounds like special tools and procedures will be needed. Besides that, I need to get back to the comfort zone of a 69 Camaro I'm doing.

It was sold as is, from an independent dealer. But maybe if I make some noise at the Chevy dealer I might get a break.

I appreciate the advice.