I have all new:
-Radiator (oem equiv from parts store, plastic end tanks)
-Water pump (bosch)
-Upper and lower hoses (gates)
-Heater hoses (goodyear bulk hose)

No matter how much I tighten the screw style hose clamps, I will get a drip coming from the radiator connection on the upper rad hose and a drip on the lower rad hose at the water pump connection.

Are people having better luck with spring clamps? Where can I get them + what sizes?

 

I had the same problem brought a new clamps... that where not made in china... and this cured the trick.... for me the bolt on the clamp was loosening as I was driving... now another thing you can try is if you have any left over hose cut a piece of hose and put it over the hose where the clamp is placed making the hose big make it big to clamp it down tighter..... do I make sense?

 

It is always recommended to get oe spring clamps from the dealer for the very reasons you are having issues with. They arent much so it worth it in the long run

 

I had a hunch, so I changed the rad cap that I had just picked up along with the water pump (Stant OEM equivalent, silver in color) to my cap that I took off. The older cap is only about a year old, also made by Stant but re-branded by Prestone (yellow sticker on top).

Now I get 0 leaks from the hose connections, Jeep runs the same. Could the new cap have been over-pressurizing the system?

 

" Could the new cap have been over-pressurizing the system?"

Maybe. Sounds like you fixed it, though.

 

Be careful not to overtighten the screw/band/wormgear type clamps.

Get em snug and then stop.

Over-tightening those type of clamps can damage the coolant hose.

 

Yeah everything seems to be OK now. Never ran into this before, strange really with all new components.