4T is very important for 4 strokers as it performs many
functions like
lubricating, cooling, etc
it does not actually burn off like 2T in 2strokers, but i dunno y
sumtimes abit amount of 4T wil be gone.....
for 4 strokers, it is encouraged to use gd quality ones as it will
affect ur engine performance....
whereas for 2 strokers, it doesn affect the performance at all,
only the gear box......but must use gd 2T lar....