2005 Cadillac Escalade ESV 155K AWD 6.0L Vortec Engine, no mods, all stock.
The truck was driven with zero oil pressure for a few minutes and started up a couple of times during subsequent diagnosis. I've asked my questions up front and put the detailed symptoms, event details, and background below. Thank you for any insight or advice anyone can give. Just trying to save money and plan next steps.
Question 1: If I have it towed to a reputable shop, what is the risk of them further damaging the engine by starting up the car to drive it into a bay, or starting their diagnosis steps from ground zero? How would a good shop go about their initial first steps to ensure they don't damage the engine beyond what it already suffered, or do most shops doing even think in those terms in this type of circumstance? Am I worrying about nothing here?
Question 2: What are the odds that this event has put the 155k engine past the point of it making sense to move forward with simply the oil pump replacement? Every write-up or video I've found about similar engines is about symptoms building over time and the owner recognizing it up front and nipping the problem in the bud after seeing the gauge bounce and hearing a few ticks. I haven't come across anyone that has had it fail outright and then accidentally driven on it for a few minutes. It seems like we won't have any real way of anticipating the viability of the engine until *after* this very expensive oil pump repair. I've having bad visions of replacing the oil pump for $1300 (at least that much since front diff needs to be dropped to drop the oil pan) and then having it throw a rod a week later.
Failure Event: Two days ago, my wife started it up in a parking lot and the low oil pressure alarm sounded. The wife ignored it for a few moments while she drove it across a busy parking lot, probably 3-4 minutes of stop and go driving before she realized the seriousness and parked it. I arrived, checked the oil that had about 4500 miles since the last change. I have a slight pan gasket or drain plug leak, so it was about a half quart low. I added a half quart and started it up for about 20 seconds. The engine was very loud, making various unusual noises, getting worse over the 20 seconds I ran it as the half quart made its way down to the pan. Obviously not a sensor or gauge problem, you could tell from the sound that the engine was not being lubricated. I had it towed home.
After I got it home I changed the oil and filter. Oil looked/smelled fine for used oil. I did not notice any metallic flakes or sludge or anything else weird about the oil itself. I started the truck up again for about 15 seconds to see if the oil change had any effect. Same super loud engine, same dry noises/ticks, almost sounded like a muffled exhaust leak coming from inside the engine if that makes any sense, just to give an idea of what the noise was like. No loud bangs, just not healthy sounding at all.
Background: I'm a DIYer and rarely bring my car to the shop unless expensive tools or major engine repair is needed, so as a result I don't have a trusted mechanic/shop. This car has run without any engine issues of any consequence for the last two years since purchased, during which I've put about 35K miles on it. Light to medium towing in the summer. I've always changed the oil around 5K miles with Mobile 1 full synthetic. Recently diagnosed/fixed an intermittent CEL with conflicting emission codes a few months ago. Turned out the K&N air filter was a little too wet and it ruined the MAF. That took me almost a year of driving and diagnosis to finally find the culprit since the CEL was so intermittent. I think this is unrelated, but lately she has been just a little tiny bit underpowered but still running super smooth. I've driven several of these vehicles for the past 15 years and I'm pretty in tune with how these rigs feel when they are running optimal or sub-optimal. It just seemed a little more gas pedal was needed and there was a little more engine noise even at lower RPMs to get the same getup and go. I was planning after the holidays on replacing plugs/wires and checking compression as a first step to diagnose that before this event happened.
Thank you -
The truck was driven with zero oil pressure for a few minutes and started up a couple of times during subsequent diagnosis. I've asked my questions up front and put the detailed symptoms, event details, and background below. Thank you for any insight or advice anyone can give. Just trying to save money and plan next steps.
Question 1: If I have it towed to a reputable shop, what is the risk of them further damaging the engine by starting up the car to drive it into a bay, or starting their diagnosis steps from ground zero? How would a good shop go about their initial first steps to ensure they don't damage the engine beyond what it already suffered, or do most shops doing even think in those terms in this type of circumstance? Am I worrying about nothing here?
Question 2: What are the odds that this event has put the 155k engine past the point of it making sense to move forward with simply the oil pump replacement? Every write-up or video I've found about similar engines is about symptoms building over time and the owner recognizing it up front and nipping the problem in the bud after seeing the gauge bounce and hearing a few ticks. I haven't come across anyone that has had it fail outright and then accidentally driven on it for a few minutes. It seems like we won't have any real way of anticipating the viability of the engine until *after* this very expensive oil pump repair. I've having bad visions of replacing the oil pump for $1300 (at least that much since front diff needs to be dropped to drop the oil pan) and then having it throw a rod a week later.
Failure Event: Two days ago, my wife started it up in a parking lot and the low oil pressure alarm sounded. The wife ignored it for a few moments while she drove it across a busy parking lot, probably 3-4 minutes of stop and go driving before she realized the seriousness and parked it. I arrived, checked the oil that had about 4500 miles since the last change. I have a slight pan gasket or drain plug leak, so it was about a half quart low. I added a half quart and started it up for about 20 seconds. The engine was very loud, making various unusual noises, getting worse over the 20 seconds I ran it as the half quart made its way down to the pan. Obviously not a sensor or gauge problem, you could tell from the sound that the engine was not being lubricated. I had it towed home.
After I got it home I changed the oil and filter. Oil looked/smelled fine for used oil. I did not notice any metallic flakes or sludge or anything else weird about the oil itself. I started the truck up again for about 15 seconds to see if the oil change had any effect. Same super loud engine, same dry noises/ticks, almost sounded like a muffled exhaust leak coming from inside the engine if that makes any sense, just to give an idea of what the noise was like. No loud bangs, just not healthy sounding at all.
Background: I'm a DIYer and rarely bring my car to the shop unless expensive tools or major engine repair is needed, so as a result I don't have a trusted mechanic/shop. This car has run without any engine issues of any consequence for the last two years since purchased, during which I've put about 35K miles on it. Light to medium towing in the summer. I've always changed the oil around 5K miles with Mobile 1 full synthetic. Recently diagnosed/fixed an intermittent CEL with conflicting emission codes a few months ago. Turned out the K&N air filter was a little too wet and it ruined the MAF. That took me almost a year of driving and diagnosis to finally find the culprit since the CEL was so intermittent. I think this is unrelated, but lately she has been just a little tiny bit underpowered but still running super smooth. I've driven several of these vehicles for the past 15 years and I'm pretty in tune with how these rigs feel when they are running optimal or sub-optimal. It just seemed a little more gas pedal was needed and there was a little more engine noise even at lower RPMs to get the same getup and go. I was planning after the holidays on replacing plugs/wires and checking compression as a first step to diagnose that before this event happened.
Thank you -
