In my desire to make my station wagon more efficient I replaced the plugs to NGK iridium spark plugs.. Much better in my opinion than the BOSCH Platinum.
NOW.. I'm determined to SURVEY and re-search if it's worth it for me to put synthetic oil in this old... but very Good engine.. It does not burn any oil and I believe it's still got plenty of power considering that it is 17 year old boxy beauty. . I've replaced old vacuum hoses.. put in a brand new air filter and have just cleaned the air intake and throtle.. . Now the OIL ?
but before I'd like to do some re-search. .I've heard the Chevron DELO 15w-40 Heavy Duty is a very good oil for old Gas and Diesel engines and that it's cualities as a super heavy duty oil are unsurpased and comparable to synthetic oils in its performance.. BUT the price is just as exceptional 1/4 of the price of synthetic at 7.99 for a 1 gallon of oil which is equivalent to 5 quarts.. .If I'm not mistaken.. Please comment on this issue and reply back to me with your advice. Tank You VOLVO much!!