rojodiablo said:
They aren't called "STEALERS" for nothing. It is a sevice managers' job to bring in as much service revenue as possible. The better he is at it, the more he makes.
" Gadget's first rule: NEVER let the dealer touch your truck!!" BTW... how do you check for piston slap without looking at a piston, or looking at the cylinder walls? Anyone??? I guess fiber optic camera or something ?? Or just by sound? Doed slight detonation "sound" like piston slap?? Anyone??
First thing, you are entitled to your opinion, but it sterotyping is a sign of ignorance. To insinuate that everyone is corrupt if they make their living by producing revenue for the company they work for is simply wrong. Even Gadget makes more money by producing more revenue, so by your definition he's stealing? I don't think so.
I am not a technician, I am a parts guy. There are several TTORA members who are experienced Toyota Technicians and Service Advisors on the board that can offer a great deal better insight than I can, but they probably wouldn't reply to your question because of your insulting forward.
Your questions about piston slap are valid.
It is not uncommon to see teardowns authorized strictly by sound (I haven't seen it done as a result of the early morning knocking we 2.7l owners are used to).
I am not aware of a Toyota-specific procedure that will result in a diagnosis of this specific issue. Generally speaking, higher than normal levels of wear related materials in oil analysis samples is one sign to the cause, type & severity of damage (if any) being caused. Also, if it is severe enough and goes on long enough vertical piston and cylinder wall scuffing/scratching or scoring on the hammering (noisy) cylinders can be seen upon visual inspection. Tear-down will normally only be authorized if oil analysis has been performed after several other confirming symptoms have occurred (for instance reduced combustion chamber compression on the hammering (noisy) cylinders, increased oil consumption and/or increased exhaust emissions.
Also, generally speaking, these issues are the extreme side for slap/knock that occurs to excess. To my knowledge, the very short, cold start slap inherent in the 2.7 has not produced any long-term issues. This is arguably one of the strongest engines Toyota has ever produced.
Good Luck!