400 Isl Radiator Overflow Tank Leak!

[Lucchese1]

My radiator overflow tank Has been leaking on every trip and I see it is leaking from the upper cap on the top left. It will leak a gallon of fluid about every 1500 miles or so. Is the cap defective or maybe the tank? I have tighten and checked everything many times and it just still leaks. Any one with same problem or any advise?

Thanks Ben!

[Lucchese1]

My radiator overflow tank Has been leaking on every trip and I see it is leaking from the upper cap on the top left. It will leak a gallon of fluid about every 1500 miles or so. Is the cap defective or maybe the tank? I have tighten and checked everything many times and it just still leaks. Any one with same problem or any advise?

Thanks Ben!

[Cruzer]

On my 2004 Allegro Bus (Freightliner) my first tank went out within 6 months and the second one went out at 2-1/2 years. All were replaced under warranty. It really is a weak design. Both times my tank leaked right where the neck is pressed and heat welded into the main body. The heat weld just doesn't hold. My Freightliner dealer said this is a common failure on Freightliner XC chassis with the side radiator.