Can I substitute my regular oil change with just a can of oil treatment and a new oil filter?

The lubricative properties of oil will last for thousands of miles beyond the recommended oil change interval. Unfortunately, the additives, such as detergents, anti-oxidants, and so on, which are made specifically to be used up (essentially, they sacrifice themselves to prevent damage to the engine) do not. If the designers of the engine provided guidelines on when to change the oil, I would trust them to know what is best for that engine. They designed that engine around certain viscosity oils, expected contamination (i.e. blow-by) and engine temperature factors, and minimum warranties...so those guidelines have more meaning than "can the oil lubricate the moving parts."

On the other hand, we could just look at the simple math: $30 to $40 to have someone change your oil for you, or $15 to $20 to do it yourself...or $2,000 to $3,000 to have someone replace or rebuild your engine when it fails. Basic maintenance is actually a cheap form of insurance. Oh, BTW, oil isn't the only fluid in your car with a finite life.

Short answer: No.

Long answer: Oil additives only do one thing: Lighten your wallet.

Oil isn't that expensive. Depending on the car, you can go sometimes up to 7500 miles between changes on conventional oil. So when oil was $1/qt, you had to change it every 3000 miles. Now that it's $2.50/qt, you complain about the cost, but you change it every 7500 miles now. Guess what? Same prices for oil, but you actually save money with the longer interval. Why? Less filters bought.

The only cleaning you have to worry about, is done by the filter. If the filter isn't doing its job, then you need to change it. I myself, will double my change intervals with a synthetic because it doesn't break down as easily, so you can go longer time between changes. I will, however, change the filter at the normal oil change interval, because running synthetic doesn't reduce the dirt and carbon that can get in the oil.

In short - no you can't. Look up on Google about oil sheer. Additives do not remove combustion acids, water, fuel or any other contaminants.

Oil is slippery because of its long chain molecules that slide over each other and also give it film strength too to resist mechanical loads. These properties are reduced over time as the oil wears out.

Not changing your oil is a short sighted and false economy that will cost you dear in the end.

dont do it youll cost yourself more money than an oil change replacing a thrown rod or blown heads

This is a bad idea. All of the oil treatments I have seen have harsh chemicals in them, they are designed to be run through the engine for a very short time and the removed as part of an oil change. Further more your oil does break down over time that is why there is a time and distance recommendation on when to replace it.

only 1 way to find out!! experiment!!

check the old oil that comes out of the filter and make sure it isnt gritty, if it isn't you can do what you are suggesting, but will still need to replace the oil quantity that is in the filter. If it is gritty then you really need to replace all of the oil.