knocking sound upon start up

[ted]

Getting concerned. 2006 V8 with 35K. Cant really blame the winter weather as its garaged.

any thoughts

 

[westwind1124a]

I have had the same noise ever sense I got mine. Asked the dealer and they said it was normal. I also checked the owners manual and it confirmed what they said. Something about a pressure valve if I remember correctly. I know what you are saying though; sometimes it sounds awful!

 

[Dbone]

Think I remember reading somewhere that higher octane gas could help alleviate the problem...

Not sure if it is true but this is what I remember reading...

Cheers

 

[Mark86]

Out of the three vehicles with the 4.7L V8 in my family, the 2005 and 2006 4Runners do not knock. The GX470 knocks on start up. We use the same exact gas in each truck. I don't think it is anything to worry about though.