My trucks clock is getting close to 400,000 miles. Today it just about killed me when I thought the engine blew. I had a flat at the dump, threw the spare on and headed off. My wife was following me back because she had to bring me the impact and jack which I forgot to put back in the truck. She calls me and says my truck is smoking like a freight train which I somehow didn't notice. Right about the time I pull off I hear a loud knock start on the engine. Get out to find oil covered all on the side of the truck, underneath, and even on my wife's windshield from driving behind me. Oil pressure reading ZERO.
I can't spot the leak visually, it's too hot and dropping oil to get underneath. I pull the dipstick and there isn't a drop in there. I had to have driven it for at least 1 to 1.5 miles like this, because I did suspect I seen a little smoke, but I passed it off from left over dirt that was in the back of the truck. Go grab 5 quarts of oil so I can start it and pull it away from the trailer so I can scoop the trailer and spray rig with the other truck. Have the truck towed back home.
After it's cooled off I discovered the oil cooler line blew straight out of the radiator. Ask me how, I have no idea as the safety clip was still attached. Repaired that, filled it with oil again, no leak, but still have a knock. After about two minutes of idling the knock is completely gone. Restart, no knock.
However, my oil pressure gauge is reading 20 at idle and only moves up to about 30 under hard acceleration. I can't recall what oil pressure I was seeing before, but I almost swear it was 40 pounds under acceleration.
What kind of oil pressure are you guys seeing at idle and acceleration?
It's going to depend on the temp of the engine, oil temp, and oil weight you used. Sometimes as engines wear and tolerances become looser, a thicker oil like 15w40 or 20w50 can help improve oil pressure. The Chevrolet LS motors are great motors, but 400k is typically end of service life for any gas motor and time for replacement / rebuild. But anything over probably 12psi is "sufficient" oil pressure.
At this point just drive it. The knock will either come back or it won't. Another good thing about the LS motor is they're relatively cheap and plentiful. Start hunting a low mileage pull out 5.3/6.0. I have a 5.3 in the corner of my shop just waiting for my 5.7 to give up.
In all seriousness I would run 15-40 in a LS with that many miles on it, especially living in the south. Time will tell how much longer it lasts but it wouldn't surprise me if you were to get a few more years out of it. I wouldn't drive it to Canada or anything though. Posted via Mobile Device
I do not know much. But I would think that the hydraulic lifter was causing the knock not a connecting rod. You might change your oil right away and have it checked for metal ?? This might help rule out damage ?
As long as you only drove it that short distance I would think things are ok.
As for your pressure, you may have opened the journals a bit ? Allowing more oil to slip by and decrease pressure.
If it were me...I would take it to a mechanic and have it checked.
It's going to depend on the temp of the engine, oil temp, and oil weight you used. Sometimes as engines wear and tolerances become looser, a thicker oil like 15w40 or 20w50 can help improve oil pressure. The Chevrolet LS motors are great motors, but 400k is typically end of service life for any gas motor and time for replacement / rebuild. But anything over probably 12psi is "sufficient" oil pressure.
At this point just drive it. The knock will either come back or it won't. Another good thing about the LS motor is they're relatively cheap and plentiful. Start hunting a low mileage pull out 5.3/6.0. I have a 5.3 in the corner of my shop just waiting for my 5.7 to give up.
With those miles... I'd probably be looking at selling that off as a farm truck, before the other shoe drops... although in the south, it might be clean enough to be worth tossing a used engine in when it blows.
I appreciate all the feed back and information posted last night. I'm going to run it for a few hours today and see how she does. My worries is that she will start consuming oil like no other if it possibly got hot. I didn't notice the temperature gauge because I started crapping trying to get her off the road when I looked down and seen the oil pressure at zero.
I drove her for about two hours last night after I fixed the busted line and filled her with oil. Hopefully I didn't mess up, but I wanted to make sure she wasn't over-heating. I'm going to drain out all the oil again today and see what it looks like. I'm scared to put 15w40 in the LS engines as I've heard from tech's about it making the rings stick. However, if it starts consuming more and more oil, that will be my only option.
I'm going to start looking for a back-up engine this year. I'm not interested in a diesel. For many reasons, too costly to repair, and most importantly I can turn wrenches on gas engines. On diesel, I know nothing about them. Not to mention, I don't need a diesel. They make gasoline engines now days that will nearly pull a house down. I'm looking heavily into swapping the 6.0 with an 8.1 big block.
As far as the guy that mentioned replacing the transmission or truck. The transmission is the 4l80 (Heavy Duty) compared to the 4l60. The transmission was completely rebuilt less then 25k ago, along with a shift kit, cooler, and lots of heavy duty parts added. It shifts like a dream, even when under load. The truck has a lot of miles, but the truck doesn't even have one scratch or dent in it. No paint peeling. No rips in the interior. Very clean interior, actually. I rebuilt the front end, new shocks, new brakes and rotors, truck is in excellent shape over-all. And ran perfect up until this incident yesterday. So no need to replace the truck.
I just simply don't understand how the oil cooler line blew out of the bottom of the radiator. I did put a new radiator and hoses on it about two months ago. However, I double checked to make sure them lines were tight, and clipped in with the safety clips good. There was no way they were coming out. It just doesn't make sense to me.
I do not know much. But I would think that the hydraulic lifter was causing the knock not a connecting rod. You might change your oil right away and have it checked for metal ?? This might help rule out damage ?
As long as you only drove it that short distance I would think things are ok.
As for your pressure, you may have opened the journals a bit ? Allowing more oil to slip by and decrease pressure.
If it were me...I would take it to a mechanic and have it checked.
Yeah, a mechanics really not going to be able to check much, short of pulling the pan and bearing caps and plasti-gauging the bearing tolerances. And at 400k the results are nearly guaranteed - due for rebuild. Might as well skip the diag cost and put the money toward another motor.
A used replacement is typically cheaper than a rebuild, so if you're not building it up there's not much reason to spend the time and money. I've bought LS motors with ~150k for $400-$600. The R&R would take a day, maybe a weekend.
Exactly what it was. The horseshoe clips. Put the odd part is, the clip was still in place on the connector. Explainable to me how it came out of there. I ensured when I installed the radiator that the thing was clipped in there good and COULD NOT be removed. I'm always careful about double checking things like that. Absolutely makes no sense to me.
Yeah, a mechanics really not going to be able to check much, short of pulling the pan and bearing caps and plasti-gauging the bearing tolerances. And at 400k the results are nearly guaranteed - due for rebuild. Might as well skip the diag cost and put the money toward another motor.
A used replacement is typically cheaper than a rebuild, so if you're not building it up there's not much reason to spend the time and money. I've bought LS motors with ~150k for $400-$600. The R&R would take a day, maybe a weekend.
When the season starts back up, I'll more than likely BOLO for a good low mileage engine, possibly from LKQ. I'll put it in the back of the shop and run this one until it dies though. When-ever I buy a replacement, in the meantime of driving this one, I'll be sure to replace the rear main seal, oil pan, and valve cover gaskets before it goes on the truck.
I'm not locating any LS engines as low as you. I have seen some 5.3's go pretty cheap. But most of the LQ4 and LQ9 6.0's I see are in the $1,500. range used. A reman engine is in the $2300 - $2900. range. But honestly, I feel I trust a low mileage used pull out engine before I trust many of the reman builder manufactures out there today. I've seen so many horror stories from them.
A local engine builder would be out of the question due to down time. My only option would be a used engine or a reman engine and as I stated REMAN engines can bring me paranoia. I've seen some pictures from these reman companies way back, that had mismatched new and used pistons, specs and tolerances out of wack, things improperly torqued, used parts in them, and so on. At least with a used GM engine for the most part you know you are getting original parts that were built to last several hundred thousand miles.
As I said, I'll probably scour the yards and lkq's inventory over the next few months and wait for the right opportunity for a low mileage one to pop up that's reasonably priced. I'd be willing to pay up to 2k for a good low mileage used engine.
Exactly what it was. The horseshoe clips. Put the odd part is, the clip was still in place on the connector. Explainable to me how it came out of there. I ensured when I installed the radiator that the thing was clipped in there good and COULD NOT be removed. I'm always careful about double checking things like that. Absolutely makes no sense to me.
That's news to me. And your sure on that whiffy? Seems like the clip would go on last, but again that could be why it came out. However, I did all the others the same way and they still seem tight. I put it back together, so I need to pull it back out and push it through the clip? Instead of pushing the line into the adapter and then attaching the half moon clip?
Also for an update, I drained the oil today, found no metal in the oil. And even more better news, the oil pressure problem is resolved. I changed the filter when I drained the oil and my oil pressure went right back to normal. Hopefully she'll be good to go for another 100k.
I'm going to have another engine on stand by in the back of the shop. But honestly, as strong as this engine has been running I could forsee it going 500-600k, along with my 5.3. Both engines still run close to the first day I got them. They've never seen a mile over 3,000 on oil changes and never a mile over 10,000 on air filters.
Gotcha. Thank you very much for passing that along! I'll go out there and re-do it today. You probably saved me from it happening again. I appreciate the help on that one. Now if I can just figure out where the water is slowly disapearing. I'm having to add coolant about once a week. I replaced the radiator and all hoses. Not seeing any drips around the water pump. So I have no idea where it's going unless I have a small headgasket leak.
Could be leaking on the exhaust side see any smoke? Those 6.0s go through water pumps like nothing else. You can probably rent pressure testers at advance - I've never tried. Mine was around $100 Posted via Mobile Device
Could be leaking on the exhaust side see any smoke? Those 6.0s go through water pumps like nothing else. You can probably rent pressure testers at advance - I've never tried. Mine was around $100 Posted via Mobile Device
Believe me, I've been through my fair share of swapping Water Pumps on them. I finally ponied up and started ordering GM Water Pumps off of Amazon for not much more then the part store ones. I've been getting 100k at least out of them.
But I got bad, bad news. I took it on a 30 minute drive today. Started over-heating. I pulled over, blowing water out the tail pipe. We know what's wrong there. Head Gasket. Well, long story short, let it cool off in the parking lot and go home. Go back to pick it up, time I make it back the bottom ends rattling.
Found another engine, 99,000 miles for $1300.00 certified, with a warranty, and 30 minutes from the house. Going to run up there and grab it in the morning and hopefully swap it out Wednesday night.
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