A used car lot had their customers recently purchased 2012 SRT Grand Cherokee brought in that wouldn’t pass a smog test. The variable cam timing monitor wouldn’t run so I had been over night road testing it and running the monitors on each trip. After a few days I noticed the engine temp was lower than I’d expect, @185deg so I put a thermostat in it and now I was getting 203 plus, yet the monitor didn’t run on my next 2 trips, so I contacted tech support. They advised, while they weren’t sure on this engine , the Pentastsr 3.6L needs to run hard and held at high RPM to run. So they advised to use auto stick to hold a lower gear to maintain a higher rpm and drive it hard and do this for 10 minutes...
Left for work early that morning and used auto stick getting familiar with the procedure, but had lots of traffic so couldn’t even do it and had to get off freeway to go another way. After getting off freeway and in more traffic I held 1st gear and tacked the engine @5k for maybe 6 seconds and saw the oil light come on then herd urrrup and the engine stalled and wouldn’t crank, I coasted off onto the shoulder. Electric power was good yet it won’t crank, nothing, just a slight click. Figure at this point It’s either dropped a valve seat, threw a push Rod, broke a rod or broke the timing chain or threw the belt and it’s wrapped around the crank dampener not allowing it to rotate. I checked the belt it was ok so time fir a tow.... I’ve never had this happen in 35 plus years And at this point I feel bad like iam responsible and caused it....
Later I verify the crank in fact won’t turn with a breaker bar so pull all the spark plugs and inspect all the pistons and Cylinders and find no damage. Next I inspect the timing chain with a camera and find its intact and not locking the crank.... now I’am like wtf?
So I come up with a bright idea, drain the engine oil into a clean container and inspect the lower end that way... we’ll it’s full of metal, brass.... so my thought now is it spun a bearing.. its AWD so pan removal is a little difficult... Well low and behold it seized all the main bearings... see how hot the main caps got ?
Thinking further it looks like it had some prior wear and metal debri was partially plugging the oil pump pick up screen and it just coincidentally failed while I was driving it..
Luckily they sold the customer a service contract, so as long as the insurance company is not dicks about it, should cover the failure... it’s got some
Modifications so I could get declined in which case I think the car lot will buy back....
Left for work early that morning and used auto stick getting familiar with the procedure, but had lots of traffic so couldn’t even do it and had to get off freeway to go another way. After getting off freeway and in more traffic I held 1st gear and tacked the engine @5k for maybe 6 seconds and saw the oil light come on then herd urrrup and the engine stalled and wouldn’t crank, I coasted off onto the shoulder. Electric power was good yet it won’t crank, nothing, just a slight click. Figure at this point It’s either dropped a valve seat, threw a push Rod, broke a rod or broke the timing chain or threw the belt and it’s wrapped around the crank dampener not allowing it to rotate. I checked the belt it was ok so time fir a tow.... I’ve never had this happen in 35 plus years And at this point I feel bad like iam responsible and caused it....
Later I verify the crank in fact won’t turn with a breaker bar so pull all the spark plugs and inspect all the pistons and Cylinders and find no damage. Next I inspect the timing chain with a camera and find its intact and not locking the crank.... now I’am like wtf?
So I come up with a bright idea, drain the engine oil into a clean container and inspect the lower end that way... we’ll it’s full of metal, brass.... so my thought now is it spun a bearing.. its AWD so pan removal is a little difficult... Well low and behold it seized all the main bearings... see how hot the main caps got ?
Thinking further it looks like it had some prior wear and metal debri was partially plugging the oil pump pick up screen and it just coincidentally failed while I was driving it..
Luckily they sold the customer a service contract, so as long as the insurance company is not dicks about it, should cover the failure... it’s got some
Modifications so I could get declined in which case I think the car lot will buy back....
