This may be common knowledge to some but if your new to towing. Make sure you only tow in DRIVE, never tow in OD. Especially with a gasser.
I would look at each vehicle on a case by case basis. My old gasser tow pig was made to tow in OD. Fuel injected 454 and 10 mpg loaded or unloaded.
Agree, absolutely case by case, not all created equal. Several HD gassers are made to tow small, medium loads and have suspension, etc to assist.
Just saying most 1500s, F150, V8 SUVs are all gonna want to avoid OD to prolong tranny life. Play it safe. Unless your vehicle is specifically made to do so. They are light duty and usually have light duty trannies equipped.