Not sure where you get your info but the tensioners are controlled by oil pressure and are made out of steel. Melting of the tensioner. Good grief. They and the chains do not get too hot. The root cause is from fuel dilution and soot caused by GDI. This is well documented by the manufacturers, oil producers and API. Thus the changes in the new API SP formulation for testing chain wear and protection. I have seen similar post on other forums and it appears you mix a little truth and a whole bunch of hype and nonsense.My 2 cents.....Unfortunately, You might have purchased a traverse that burns oil, and the previous owner drove the traverse with low oil. Burning oil is common in these "small" gdi engines, relative to the heavy weight of the traverse , via the process called LSPI.
A dealership saying getting a new engine could easily be a money making scam for the dealer. Big markup for dealer on a rebuilt or refurb engine, plus all the work to install. Compare prices,shop around, understand what the replacement engine is.. refurbished or remanufacted.
Since the traverse engine is an interference engine, I would think
the pistons and intake valves would have had to crash into each other and cause enough other damage,,, to warrant a new engine. Has the dealership provided evidence of why a new engine is needed?
If we start at the beginning..........
I would say this GDI engine burns oil. Burning oil is root cause of your traverse engine failure.
When you drive with low oil, you get no oil cooling of the timing chain system, resulting in a very HOT timing chain, resulting in wear (MELTING) of the plastic timing chain tensioner, which then does not keep chain tight in between sprockets, and then over time ... will wear the links of the timing chain over time.
The stretched timing chain could eventually cause a crash of the interference intake valves and piston.
I would evaluate the cost of fixing the following....
---->> to fix the burning oil consumption problem, new pistons and rings would be needed.
The cylinder walls should be OK unless interference crash damage, or the previous owner used crc intake valve running engine cleaner since that process will scratch cylinder walls or ? (Need to inspect)
New timing chains system is also needed.
Get the intake valves carbon cleaned off intake valves during this process.
Compare that cost ^ ^^^ of fixing
to the cost of a superior remanufactured engine,
where the Remanufacture has made improvements to the OEM design ( like upgraded piston and rings and ?)
Shop around, the dealer will be the most expensive.