IMHO your over towing. With personal belongings and gear your probably in the 6K range. If that's your rig in your avatar it looks to have 35-37" tires plus I'm sure you were running the AC.
With 320K on the clock it was a time bomb waiting to happen. 🤷♂️
Non Lifted stock tires these...
Something doesn't seem right, these usually let go on number 6 cylinder by the firewall and usually the spark plug on the cylinder that let's go is steam cleaned squeaky clean.
Of course there's an exception to every rule.
The bottom end on these are very Stout and your oil burning could easily...