high millage oil question

[exprunner11]

i was thinking of switching from Valvoline max-life synthetic to just normal Valvoline synthetic motor oil but would doing this cause the seals to leak due to the swelling of the seals also it doesn't leak now or before i did switch it to the high mileage oil.

 

[R1dd1cK]

Well if it didn't leak before you should have never switched. Switching away from the high mileage will more then likely make it leak.

 

[exprunner11]

ya that's what im thinking but the reason is swithched at the time was the timing chains were stating to rattle

 

[swshawaii]

4. How is MaxLife Synthetic motor oil different from SynPower Synthetic motor oil?

MaxLife Synthetic motor oils contain stop leak additives to help with oil consumption and extra detergents to help with the cleaning of an older engine.

http://www.valvoline.com/faqs/motor-oil/high-mileage-motor-oil/

 

[my98nnj]

As per the above post, switching after you've introduced sealing additives isn't a good idea. You need to continue to use the same stuff for the life of the engine.

 

[AP9]

Folks at BITOG tend to think it's fine:

http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2463279
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2971046

The synthetic oils of today are much better than the synthetic oils of 20 years ago.

Now granted, the seals may eventually de-swell and start slowly leaking again after awhile, but I don't see why a good modern SN-rated synthetic like Valvoline should cause a sudden problem.