Mechanic says the noise my engine is making is from the Timing Chain. Is my mechanic right? Can the timing chain really be off track to cause the rattling noise I'm hearing?

The growling noise that you are hearing when you accelerate is likely caused by a problem with your timing chain. The timing chain is a critical component in the engine that helps to synchronize the movement of the pistons and the camshafts. If the timing chain is loose or damaged, it can cause a growling or rattling noise, especially when the engine is under load. This can be a serious issue because a faulty timing chain can cause the engine to misfire or even fail. If you are hearing this noise, it is recommended that you have your vehicle checked by a mechanic as soon as possible to diagnose and repair the problem.

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When I read --mechanic suggest a rebuild / replacement --I always suggest to find a trained mechanic for a second opinion
The book shows that it is a 5.7 L engine EZD, EZH(vin8 =T) 2009-12 manufacture
It has a timing chain and has 1 spring loaded chain adjuster and one fixed chain guide
I suspect that the guide surfaces are worn to metal - screeching-- and the knocking is a badly worn chain just about ready to break
Get an opinion from an accredited service center that has experience on jeep products

Have they check the power steering pump?

Get a second opinion ! I don't know what actuator was replaced, but a starter or anything in the start circuit will not set off a check engine light.
The very first thing a mechanic would do is to plug in a hand held scanner to the computer and see why the light is on. There is a trouble code stored for why the light was turned on. The computer has no way of defining a bad timing chain, no sensors there. Ask the mechanic what codes were present.. If you don't like his answer, go somewhere else for a second opinion. Timing chain failure is pretty rare. It can happen, like if a sprocket gets too worn and the chain may jump a tooth, throwing off the engine timing and causing a rough running condition, but it is still rare.
Your mechanic has the advantage of being there and knowing the symptoms at hand. You have shed no light on symptoms or what the problem is, so I feel disadvantaged when giving advice. I will say this, though. You cannot really tell if the chain is the problem, and neither can he, until the front of the engine is stripped down and checked . And that's a pretty pricey option right there. So I see it as a judgment call: Is he honest and forthcoming, do you trust him? I would be inclined to get another opinion if I had the least doubt.

Tow guy probably correct
If it has a chain and you have not been paying attention to regular services, it is possible for a badly worn chain to wear through the timing cover and let oil escape
The mechanic you took it to was probably not properly qualified as he should have seen the oil spray , found the problem and gave you a report on what he found

The timing chain tensioner is self adjusting.....Here is some info you can read...

I recently purchased a 2004 Ascender with the 4.2l in-line six cylinder motor, and under the 60 day warranty, the fan clutch and water pump had to be replaced. The mechanic told me that the fan clutch wears out causing an out-of-balance condition which puts extra strain on the water pump, which was leaking. Another issue may be that the timing chain needs to be looked at, because the tension wheel/gear for the chain wears out, making the timing chain sloppy. Then the chain flops around inside the housing, making a similar noise to the one you describe. Have your mechanic/technician check it out.

It definately has the miles to need a timing chain. but yhe steering problem has nothing to do with it. Mechanics are like Dr.s Get a second opinionfrom someone that is more for you than the buck.

yes i would for sure ! it will save you money later./