Purpose and Specifications

STP STP63300 Engine Stop Leak is a 300ml additive designed to stop engine oil leaks in both petrol and diesel engines. It renews and protects worn polymer seals and gaskets, swelling them back to original shape to prevent leaks without harming your engine.

This middle-class STP product weighs just 0.3215kg and fits easily into your maintenance routine. Add one 300ml bottle to 4-5 liters of engine oil at every oil change to keep seals flexible in operating temperatures from -20°C to 150°C. Expect results within 500-1000km of driving, with effects lasting up to your next oil change at 10,000km or 12 months.

• Stops oil leaks fast by conditioning seals
• Works with all engine oils for petrol and diesel vehicles
• Shelf life of 3 years unopened; use within 6 months once opened

When to Use / Replace?

Use STP63300 when you spot oil drips under your car or notice low oil levels between changes, especially on high-mileage engines over 100,000km. Pour it in during your regular oil change every 10,000km or 12 months to maintain seal health and avoid bigger repairs.

Replace the treatment's effects with a fresh dose at each oil change; don't exceed one bottle per 5 liters to keep oil flowing smoothly in cold starts down to -20°C or hot runs up to 150°C.

Frequently Asked Questions

Is STP63300 safe for modern engines? Yes, it's formulated for low-viscosity oils in today's petrol and diesel engines, reducing wear without clogging filters.

How soon does it stop leaks? Seals start swelling within 500km, fully effective by 1000km under normal driving.

Can I use it every oil change? Absolutely, add one bottle per 4-5 liters at every 10,000km or 12-month interval for ongoing protection.