Originally Posted By: 01rangerxl
This type of clamp is designed for quick assembly and to reduce variables in tension that come about with worm clamps. A manufacturer can put these on quickly, and not have to worry about them leaking for the life of the hose. Once the hose needs replacing a decade or so later, it's your problem.
I figured out why the OEMs like these so much when I bought a Motorcraft radiator hose for my truck with these pre-installed. They were glued on at the right places on the hose, and locked in the open position by a tab. Just slip the hose on, release the clamps from the open position with a screwdriver, and you're done. It took literally seconds to put the hose on and clamp it. No question about if the clamps were positioned in the right spot, if they were tight enough, etc.
Here is a hose with one of these clamps pre-installed...noticed it is locked in the open position. All you have to do is take a flat screwdriver, place it between the tabs, then twist...
The problem is, it is hard to find replacement clamps, they are tricky to get off, and without the glue holding them in the right spot, releasing them could be a challenge (you can return them to the locked open position). The OEM doesn't care about this being easy for you at home though, not when they can save a significant amount of time during assembly and avoid potential warranty claims from worm clamps that may not hold tension like they should.
I have mixed feelings about this type of clamp. I like that they hold constant tension regardless of temperature, and that they don't cut into hoses like sharp edged worm clamps can, but they can be frustrating to take off and re-install. When they are pre-installed on a hose, they are great until you have to take it off. I have never had a problem with leaks when reusing these. The only hoses I have ever had leak were secured with worm clamps. I have lost one when it flew out of the pliers and off into some corner, never to be found again.
It would be less of an issue if aftermarket hoses came with these pre-installed like some OEM replacement hoses do. It really is a smart design from an initial assembly standpoint, it just doesn't take into account ease of removal.
I think a good compromise are the wire type hose clamps used in many Japanese vehicles. Less damaging to hoses than traditional worm clamps, but still easy to remove and reinstall. Not sure how they compare with holding tension, but they seem to work well...
I wish this type of clamp was readily available at parts stores. It seems like they wouldn't cost any more to produce than a regular worm clamp, but are likely much better and definitely less damaging to hoses. Not sure why they haven't been used more widely.
I remember the days when the factory (I think it was Ford) used to staple those wire-type clamps to the hose.