Motor oils are carefully formulated lubricants that perform many important functions, including cooling engine parts, keeping them clean, and protecting them against rust, corrosion, and wear. One of the most important functions of oil is providing lubrication by forming a cushion between moving parts to help them slide more easily. This reduces metal-to-metal contact and friction — a major contributor to heat, wear, and premature aging of engine parts. STP® Oil Treatment fights this metal-to-metal friction by providing a thicker cushion of oil between moving engine parts, thus helping to protect against engine wear.
STP® Oil Treatment can be added at any time. For maximum results, it’s best when added to fresh oil in a warm engine right after an oil change.
There are two separate and distinct STP® Oil Treatment products:
STP® Oil Treatment (in the blue bottle) helps protect against engine wear with a high-viscosity formula, which fights metal-to-metal friction by providing a thicker cushion of oil between moving engine parts. It can be used in all cars, trucks and SUVs.
STP® 4-Cylinder Oil Treatment (in the red bottle) also helps protect against engine wear by increasing oil viscosity, which provides a thicker cushion of oil between moving engine parts and reduces metal-to-metal friction. It counteracts oil thinning and also contains additives to boost motor oil’s anti-wear protection. This product is optimized for 4-cylinder engines.
Sludge is a thick, sticky residue that can form inside your engine through a combination of combustion by-products (oil oxidation residue, carbon and water). Water condenses as a result of a hot engine cooling down. The oil mixes with the resulting water and forms a thick sludge that sticks to the engine parts. Frequent cold starts and short trips contribute to this condition by not allowing the engine oil to heat up enough to vaporize and remove the water. Sludge is detrimental in that it can clog key oil passages such as oil drain-back holes and, in some cases, block the oil pickup screen in the oil pan, causing engine oil starvation (i.e., not enough oil). STP® Oil Additive products contain detergents, which can help suspend sludge in the motor oil and prevent it from accumulating inside your engine.
No. STP® oil additives contain detergents, which can help suspend sludge in the motor oil and prevent it from accumulating inside your engine.
STP® Oil Treatment products can be added at any time and are best added at every oil change. They should, however, only be used once per oil change.
The 15 fl. oz. STP® Oil Treatment products are designed to be mixed with 4—5 quarts of motor oil.
Many car manufacturers state that after-market oil additives are not necessary, even though they sell their own brand of oil additives. Some after-market oil additives contain corrosive chemicals, including chlorine-based lubricating compounds that may be harmful to internal engine parts. STP® products do not contain any corrosive components and are safe for use in all engines.
STP® does not manufacture an oil treatment specifically for winter use. Both the STP® Oil Treatment and STP® 4-Cylinder Oil Treatment can be used year-round. If you prefer a lower-viscosity formula, use STP®4-Cylinder Oil Treatment, which can be used in cars, trucks and SUVs with engines of any size.
STP® Oil Treatment has been used successfully in manual transmissions, gearboxes and differentials at a 10% treat-rate by volume (i.e., 90% oil and 10% Oil Treatment by volume). Do not overfill.
The STP® oil additive products have not been tested and are not recommended for use in two-cycle engines.
The STP® oil additive products are specifically designed for use in four-cycle engines.
We do not recommend using STP® Oil Treatment products in home heating oil.
© 2021 Energizer Auto. STP is a trademark of Energizer Auto.