Head Gasket Paranoia

You can't just change the head gasket You're going to have to take the head off the engine check the piston deck heights at top dead center Make sure they're correct there's a number and all of that and then look at the back of your engine assembly facing the firewall and look for cracks in the girdle and in the center section of the engine noting that the engine is a bunch of aluminum pieces stacked on top of each other The oil pan the girdle the reciprocating mass in the center section the head is bolted atop this

 

Any cracks or funny business or any weirdness in the deck height stop right there none of this can be machined to be fixed you'll be doing something else for sure if anything arises at this point

 

Check Carfax.

Was the coolant changed, spark plugs, engine oil, brake fluid flush, transmission oil, water pump? I'd go there. Overheating is the single most contributor to headgasket failure, not EGR. That said, the headgasket may already be failing.

 

Judging from the miles and symptoms, it might have a stop-leak product in the engine coolant.

Overheating is not normal. Could be a failed water pump, overdue coolant replacment. Lessee, what else?

 

It the winter it's common to get a rattle at start up because of condensation.
Is the coolant level low? If it is, and there are no leaks, it might be a failing head gasket.

Changing the head gasket before it fails would not be a back thing. I had planned on doing
that, but it failed a week or so before i was going to do it.

Check the valves for leaking, seat them ALL in if even one is leaking at all. And of course
new valve stem seals.

And while it's apart, clean the egr cooler, intake ports, and everything else.
Check the impeller for the water pump for cracks. If it show any signs of wear, replace it.

Might as well change the inverter coolant while you are at it.

When filing the coolant, go very slow, about a cup or two a minute. You'll hear it seaking the
lowest point and pushing out the air. Then you won't have any issues with air gaps.
And fill to the "B" line.