Unfortunately at this point the radiator was no longer holding fluids for long. It had lost sealing at the top and bottom tanks and had an especially nasty crack near the lower radiator hose barb - any fluid put in would begin leaking out immediately.



On the other hand, the new Toyota radiator's core is actually wider than the original; it bolts up and fits to the same points while adding cooling capacity, but discards the separate side brackets for mounts directly on the radiator flanges. This is a problem for me as the truck has an aftermarket transmission cooler; the installer routed the hoses around in the gap between the radiator bracket and the opening in the radiator crossmember. There isn't enough space there now to fit the radiator with the hoses in place and there's not enough hose to route it any other way. The hose splicing was also kind of garbage - I'll pick up some new hose splices and hose to get the job done properly today.



For anyone taking a data point, my thermostat turned out to be an original Toyota unit with the jiggle pin at the 12 o'clock position. I replaced it with a new Toyota one, jiggle pin set to 6 o'clock.