I had SN95 heater tubes leaking right at the 2 piece joint that screws into the intake manifold. Leaking like a water hose with a thumb over it! I was asking around, trying to find a new set of tubes, or find out if these could be fixed... I couldn't find any replacement tubes for an SN95, and everyone told me they were not serviceable. Since the set I had was leaking, and I figured I couldn't make it worse, I decided to take them apart and see if I could repair them. I took off the lower threaded portion of the joint, and found 2 grooves on the inner portion that appear to have had o-rings in them. So I cleaned them up, installed some o-rings, lubed it up, put the lower portion back on, and used a punch with increasing diameter to expand the bottom swedge back into place. I put 17# on the system, and it held fine. Then I drove it today with the 13# cap, and it didn't leak a drop. So if you were wondering, the heater tubes are serviceable at the spinning joint.