If you have a stuck compression ring, you can use Berryman B-12 Chemtool Fuel System Cleaner (part #0116) for combustion chamber cleaning if want to perform a cylinder soak. That is accomplished by pulling the plugs, putting 0116 in each cylinder (or at least the cylinder you know to be a problem), letting the product dissolve the carbon, and then removing the mixture from the cylinder(s). If you have a V-configured motor, then it may take nearly a full bottle of 0116 per cylinder to ensure that you cover the entire compression ring, especially if that ring is stuck and allows some of the B-12 Chemtool to migrate toward or into the crankcase. However, if you don’t mind soaking one side at a time, you may be able to jack up one side of the vehicle to flatten that bank of cylinders a bit and thereby cut the amount of product required. You can also buy Berryman B-12 Chemtool Fuel System Cleaner in a 1-gallon size. That part number is 0101. If you have a stuck oil ring, you can use #0116 for the removal of gum, sludge, and other crankcase deposits. However, it should only be applied immediately before an oil and filter change due to the potential overloading of the oil with dissolved sludge and deposits