not sure about that motor, but have you at least tried taking the valve covers off and pullin' on the rockers by hand? if one is looser than the others that I'd hazard a bet that that's where your problem lies..easy way to confirm or dispel the notion that it's a valve adjustment problem <img src="/forums/images/graemlins/kewl.gif" alt="" />

I dont think it has rockers, the cam rides directly on top of the shims, which from what I read I need to check with a feeler guage and compare to factory specs.

Ahh my mistake, either way, seems like a simple check, go pick up some feeler gauges and pull those valve covers off. I guarantee if you take her in for a valve adjustment when it really doesn't need it, they'll charge you anyway heh, might save yourself some $$$

Where is this "write up" of Roger's? <img src="/forums/images/graemlins/wink.gif" alt="" />

Heh, my bad, Roger's writeup is for the 22RE, I didn't catch on to the fact that you have a 3.0 until it was too late.

The adjustment really is not that bad. Get a feeler gauge and check the clearences. If you find out one is out of adjustment you can buy a shim kit from toyota. One thing is to remember and put all the cam bearing caps back in the same direction and place as you took them off. When the cam is ground the bearing caps are ground along with and fit perfectly where they are. I belive the torque specs are 22 ft.lbs. for the caps but double check. Once you dig into it I think you'll find that as long as your measurments are true and everything goes back into place, you will be just fine. P.S. Do not forget to have the engine cold when making your measuments.

I may be incorrect on some of this, so feel free to point it out, but i'll put in my .02 worth. My experience with tappet style valves is only with motorcycles, but the same principles should apply. The way i understand it, on a head that uses the bucket/shim system can't get "looser" (with respect to the cam anyway) with wear. If the valve is wearing, the clearance should actually get tighter, basicially, the valve seat is wearing thinner and since the cam rest directly above the valve the valve spring pushes the valve closer to the cam. If this is the case then that means that a valve wearing down is actually likely to make less noise(from less slop), but make the truck run worse since the valves are no longer closing all the way. One indicator on my bike was hard starting, especially when cold, once again due to the non sealing valves, which of course means lower compression. The noise would seem to indicate a valve sticking in the seal and then "popping" back up to seal when the piston started it's compression stroke.
One other thing, I had a 90 that i had a new v6, straight from the toyota factory, and it had a little ticking noise too. Never could figure it out, and the toyota tech said every engine he's ever installed from toyota sounded like that. Anyway, thats my thought for the night.