‘07 Denali XL, should I invest?

[dictum]

$2200 is a pretty good deal. Even with some rust and high miles. My Tahoe with 5.3L and 4L60 kept going strong at almost 270,000 miles. The mileage does not mean much. Change all the fluids, change parts and you can easily make it to 350K miles.

some of the big trucks on the road make it to far higher miles than this.

 

[dictum]

Tune the engine meaning the PCM with DiabloSport tune, I did that to a Tahoe and it became a totaly different vehicle. Canned mid-Octane tune. Very nice. Feed it only midgrade stuff or premium.

 

[dictum]

I would recommend installing new heater hoses and the plastic fittings at the firewall. Those can be a frequent failure on higher mileage vehicles. Our 07 Tahoe with 145K miles burst the hose at the firewall just as we were returning home, spewing coolant. If this would have happened in Dallas traffic it would require a tow. I was able to purchase both GM hoses and fittings from Rock Auto for about $100.

This exact thing happened to my 2008 Tahoe as well at around 180K IIRC. I was able to cool it off, patch it make it home late at night but you don't want it.