The cooling system on these are difficult to purge the air from. Try using a “spill free funnel” and parking facing uphill to get the air bubbles out of the engine. You’ll also want to turn your heat and rear heat (if equipped) on as well.
This is the spill free funnel that I use: Lisle 24780 Spill Free Funnel with Standard/GM/VW/Ford Adapters
https://a.co/d/hwSliuB
EDIT and slight rant: Why are people assuming it’s the head gasket? Isn’t it much more likely that there’s air pockets in the cooling system from having to drain the system to replace the radiator?
Where has diagnostic reasoning gone? Ever since I did “X” then “Y” has happened. THAT’S BECAUSE “X” CAUSED “Y”!!! “Ever since I pulled this fuse my radio stopped working, could it be the battery?” NO!!! IT’S THE MISSING FUSE!!! “Ever since I replaced my valve cover gaskets I got a P0171 lean code, could it be my injectors or my air/fuel sensor?” NO, AGAIN! IT’S THE VACUUM LEAK YOU CAUSED BECAUSE YOU DIDN’T PUT THAT VACUUM HOSE ON OR DIDN’T PUT THAT INTAKE GASKET BACK! See where I’m going with this?…
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2000 SR5 V6 Manual 4WD
https://www.toyota-4runner.org/3rd-g...biography.html
2000 Limited V6 Auto E-Locker Sold 3/2022