RE: what is afterrun oil?
There's no seals inside your nitro engine to ruin. Matter of fact because if it's great cleaning and lubricating properties and the FACT that there are no seals inside your nitro engine to ruine is a GREAT reason to use it. Transmission fluid AND "after RUN" oil are both detergents designed to CLEAN and lubricate. The reason an engine that has had after run oil used on it consistantlly is clean inside is BECAUSE of it's (strange coincidence) cleaning and (another strange coincidence) lubricating properties. If you are running Traxxas fuel I would stronglly recommend useing either Transmission fluid or "after run" oil to help keep the unburnt ignitors in the fuel from building up inside the engine.