High mileage oil?

Ok so i was wondering if high mileage oil is worth it, or if it is just a way for them to charge more for virtually the same product. I have come across threads that argue it both ways, but was wondering if anyone actually is an expert in this area that cares to share their opinion. I use synthetic in my truck, but i am actually wondering for my wifes car. She has 150000 miles on it and it runs well, and I never have to add oil between changes. I always hear that high mileage oil has "extra additives" in it. Does it really, and what do they do?

 

HM oils generally have what is called "seal conditioner" additives. This is usually repeated mistakenly as a "seal swelling" additive. The seal conditioner additive is designed to make the seals more pliable and therefore better able to seal around the bearing surface. There is also more detergent additives to help with clean the varnish and light sludging that may occur also. Should be noted that HM oils are not a cure all if you actually have a torn seal but do help if you have slight weeping around a seal.

I have a high mileage Chevy Cavalier and Kia Sportage in my family of cars that have benefited from the use of HM oils when they started to exhibit weeping around the front main and rear main seals.

My recommendation is to just keep using the same oil if you have not had any problem. Just keep monitoring your engine each oil change and only switch to a HM if need for any slow leaks or weeping.

 

Awesome, thanks.

 

My wife has Hm. Subscribe