Thanks again for all the info! I checked out the Tacoma site and they agree it is piston slap and not a problem. Evidently Mobil 1 synth and an oil filter with an anti-drain valve will help, as the noise is annoying to me.
My '97 4 cylinder (man. trans., 140K) has a loud, hollow, metallic knocking sound on cold startup. It dissapears in a minute or two, doesn't happen in summer and gets worse as temps drop in winter. Anyone know what it is?
Thanks
