Toyota: Engine Oil for Motor Car, jeep cj7, second hand car

Question
I am new driver with a second hand car.  I wish to know whether different brands of engine oil can be mixed in the container?  I am not sure what kind of engine oil is using but was advised to add more engine oil while checking the oil level in the petrol station.  

Answer
Hi Jacky,

Its usually ok to mix brands of oil short-term but not types.  If you had synthetic oil, then you should stay with synthetic.  If you had old-fashioned dinosaur juice, you should avoid adding synthetic oils.

When I buy a used vehicle, I usually have the entire engine flushed, filter changed out, and choose a brand of oil that I'll use in it for as long as I own it.  I have had extremely good performance doing this.  My 1974 Luv truck kept running well from 1986 to 1995 when I sold it.  My 1976 Celica GT ran well from 1986 to 1996 when I sold it.  And now my 1976 Jeep CJ7 is still going :-).  I use Castrol GT 20/50 in my older vehicles and Valvoline (whatever weight is recommended) for my newish vehicles (1998 Tacoma that I bought new in 1998, and 1996 Tercel bought repossessed in 1996).

Hope this helps,
SherryB