5th Gen oil change frequency and strange engine sound

[tlars]

I am a new 5th Gen owner of a Trail 4Runner and Toyota says change the synthetic oil every 10,000 miles. I have never done that. I was thinking every 5,000 miles. Any thoughts?
Also, I get a strange sound from the front of the engine compartment when I shut the engine down. It appears to come from a strange looking device on the passenger side. It makes a moan when I shut the engine off (Kinda like a diesel turbo when shifting a manual transmission). The dealers says this is a release of the vacuum systems. Does anyone have this soumd?
Thanks.

 

[G.I.G.]

I can't speak to the moan, as I am a 4th gen owner. However, regarding the oil change intervals, I would follow Toyota's recommendation and change with synthetic at 10k intervals. 5k intervals would be overkill with synthetic oil and Toyota wouldn't recommend anything that could potentially harm the engine.

 

[hearno]

Strange looking device on the passenger side? You've got a UXB in your motor. It's gonna blow.

 

[Friggin Idiot]

I didn't like the look of my oil at 10kmi oil changes, so I do every 5kmi.
http://www.toyota-4runner.org/4th-gen-t4rs/116457-brief-whirring-revving-noise-startup.html

 

[Whiplash Willy]

I am a new 5th Gen owner of a Trail 4Runner and Toyota says change the synthetic oil every 10,000 miles. I have never done that. I was thinking every 5,000 miles. Any thoughts?
Also, I get a strange sound from the front of the engine compartment when I shut the engine down. It appears to come from a strange looking device on the passenger side. It makes a moan when I shut the engine off (Kinda like a diesel turbo when shifting a manual transmission). The dealers says this is a release of the vacuum systems. Does anyone have this soumd?
Thanks.

That noise is the Air Injection Pump. It runs the first min or so when you start the car for emissions. When you shut off your engine, the pump does a reverse spin, to attempt to remove any moisture from the pump, for longevity reasons.

For more info, read my thread:
http://www.toyota-4runner.org/5th-gen-t4rs/144685-air-injection-pump.html

10k mile oil changes with the 0w-20 Synthetic oil is fine. Users have sent oil samples to Blackstone for Analysis, and their labs show the oil still has some life left in it.

 

[thzpcs]

I go off what the manual says. Time and time again people talk about doing 5k oil changes, and every time it's sent off to an oil analysis place, they said it would have been fine for 10k. Unless I'm racing it, I go off whatever the manual says. Modern oils are very durable and last a lot longer than they used to.