How much can it tow

I tow w my turd gen Prius(s) regularly. Here's the limits and abuses/concerns:

I use a Kuat bike tow hitch and put two bicycles on the back. You won't even notice it except your fuel economy drops to 30mpg. I usually get 35. I have a heavy foot and we have high speed limits here...

I use a 5x8 utility trailer that I removed the tailgate from so that I can improve my fuel economy when towing it. I can put two motorcycles on it and do 79 mph all day long even through the hills of Gainesville, Florida. I will tell you that you will suck the battery down on the uphills in Gainesville and this heats up the battery pack. It's better to not use cruise control in these situations so that you can maintain a steady state on the batteries. This keeps them cooler allowing more. Regen when it comes time to use the brakes and it preserves battery life.

I tow a 4,500 lb boat. When doing so in Florida and temperatures up to 94 Fahrenheit where we have flat terrain I can achieve 65 mph. At this speed. The engine is redline the whole time and eventually the high voltage system goes into a protective limp mode limiting me to 80% power. This happens after about 15 minutes at full throttle. When I get to the boat ramp I can achieve full protective mode where the car stops charging the 12 volt system and then it stops charging the high voltage battery. It throws warning lights all over the dash and I have to shut the car down because there are so many alarms beeping that I think it's going to blow up. One time. I pulled a 4x8 enclosed trailer with around 4,000 lb in it. So the total combined weight was probably 5,000 lb. I got the system so hot. I could smell burning electrical wires but the car has still worked fine for 100,000 mi since then.

So hopefully this helps you understand the limits of what you can do with your car and what the consequences will be. Yes all the Priuses still work and they both have over 250,000 mi. For some reason I haven't destroyed them yet doing this. Don't recommend it though. Drive safely and use at your own risk.

Oh, and by the way, since you're stopping distances will likely be more than doubled if you don't have an engineering degree or work as a mechanic or a CDL truck driver, please don't do this on public roadways. Since you're likely to hit somebody. You cannot appreciate how long your stopping distance will be and you are probably going to be unsafe.

Edit :: I use 0w40 mobile one and have read the oil pressure on the back of the engine. I wouldn't try any of this with 0w20