I have a push mower that I got for free that smokes a little and knocks when it runs. What additive would help with both? I was considering either the grey high mileage stop or blue regular bottle stp oil additive since it's super cheap and really thick and has good reviews. Are there any other additives that might be better?
GREY STP High Mileage Oil Treatment + Stop Leak, 15 fl. oz.
http://www.walmart.com/ip/STP-High-Mileage-Oil-Treatment-Stop-Leak-15-fl-oz/19897926
BLUE STP Oil Treatment, 15 fluid ounces, 8262, Oil Additives
http://www.walmart.com/ip/STP-Oil-Treatment-15-fluid-ounces-8262-Oil-Additives/16817398
GREY STP High Mileage Oil Treatment + Stop Leak, 15 fl. oz.
http://www.walmart.com/ip/STP-High-Mileage-Oil-Treatment-Stop-Leak-15-fl-oz/19897926
BLUE STP Oil Treatment, 15 fluid ounces, 8262, Oil Additives
http://www.walmart.com/ip/STP-Oil-Treatment-15-fluid-ounces-8262-Oil-Additives/16817398