4.0 lower rad hoses with the spring are still around, but not from aftermarket sources. There are still a few OEM hoses around from the dealer, about $20, at least for the HOs. Don't know if the Renix hoses are the same. With a hi-flow water pump (as I have) I'd never have a lower hose w/o the internal spring. I tried a Goodyear "reinforced" rubber hose for awhile - it eventually collapsed and caused overheating while in hi-heat traffic, so I crap canned and found an OEM w. spring.