There are two types of band clamps. One is a butt-joint clamp, which is the same diameter over its whole length. It's made to butt two pieces of pipe that are the same diameter together, without having to use an adapter or sleeve.
I guess I did it wrong. I used the non shouldered butt joint type on a normal slip joint and it still tightened down and created it's own shoulder. I can get pics if you all would like.There are two types of band clamps. One is a butt-joint clamp, which is the same diameter over its whole length. It's made to butt two pieces of pipe that are the same diameter together, without having to use an adapter or sleeve. The other is a lap-joint clamp, that is made for connections where the OD of one pipe slips into the ID of the other. The clamp is actually stepped in its diameter to accomodate this.
I don't see the point in putting a sleeve over the butt joint and using two clamps. That just doubles the number of potential leak points. A joint should never support the weight of the exhaust system anyway; even with the old-school U-clamps, you should always use a clamp that is _not_ also holding a joint for attaching a support hanger. You don't have to tighten support clamps down nearly as tightly either, since you're not creating a seal.
I guess I did it wrong. I used the non shouldered butt joint type on a normal slip joint and it still tightened down and created it's own shoulder. I can get pics if you all would like.
Well see what happened was, I planned to cut out the "cat" and muffler on my 94 psd. So I measured the pipe in between the cat and downpipe flange. Okay three inches, good to go. Went and bought a ten foot stick of three inch flexpipe. I was just going to use the flexpipe as delete pipes, until I realized the pipe coming out of the cat was three and a half inches.You did it right, the flat clamps are for slip fit pipe, the step clamps are for flex over hardpipe. I suppose a flat could hold a butt joint together , wont be strong though and could crack the stainless if improperly supported.
And I use a squirt of muffler putty on the joints of the flex on the big trucks to keep the fumes out of the cab. Seems they always leak near the heater inlet.