Getting a knocking noise

[JohnnyT]

When I start up my truck in the morning, after about 5 sec I get a knocking noise coming from what seems like the inner dash or firewall area. Can't hear it when outside the truck.

I hear it when backing out and then after about 5 minutes of driving it stops seemingly after the engine is warm. This is usually happens on cool mornings or when starting after the truck hasn't been used for a few hours.

Any ideas?

Thanks

 

[03_4x4Runner]

My guess is piston slap. http://www.toyota-4runner.org/4th-gen-t4rs/34246-cold-start-engine-noise.html

 

[JohnnyT]

My guess is piston slap. http://www.toyota-4runner.org/4th-gen-t4rs/34246-cold-start-engine-noise.html

I believe you're right. It's definitely a knock, not a tick.