Water pump replacement or just a kit

I have a 99 with 270K miles that is overheating. I suspect it's the water pump. Should I just replace the entire WP or should I just use a kit to rebuild? I do hear a whining sound at startup for a moment. Could be bearings from WP? Thoughts?

 

When was the T-Belt replaced? Was the water pump replaced then? 3.4L?

Regardless, You probably need to get a T-Belt kit that includes an AISIN water pump and plan to do a T-Belt and water pump replacement. Make sure you get TOYOTA or TOYOTA Supplier parts. You need the T-Stat too. And its rubber gasket. Plan on replacing the radiator. They don't last. Mine was shot at 125k miles. This will also prevent the pink milkshake.

Water pumps are not rebuildable...never heard of that one.

 

Kits are the way to go. New pulleys, belt, etc. I bought my 4Runner with 300k and did the radiator. Decided to just throw a water pump and belt on for general maintenance. "Pretty easy" and nice insurance.

 

I suspect the whining at startup is the fan. Overheating could be due to fan not working as it should, thermostat needing a replacement, radiator needing a flush or water pump needing a replacement. Worst case scenario, there may be a crack in the head but you'll notice it by seeing white smoke in the exhaust and loss of coolant. Assuming that we're not talking worst case scenario, when was the timing belt replaced and was the water pump replaced at that time or not? If it has been more than 120K miles since this was done, you should consider doing it all. There are kits that come complete with everything. It is not an easy task.