Engine Mechanical
Piston Ring Set
Piston rings seal combustion pressure above the piston and scrape excess oil off the cylinder walls. We carry 32 piston ring sets from $22 to $240 by Sealed Power, DNJ Rock, VR Gaskets, Mahle and Beck Arnley, with most fitments for Dodge Dakota and Ram 1500 engines plus Mini Cooper, Toyota and Porsche 944.
Shop piston ring set by vehicle
Signs of worn piston rings
Worn rings let oil reach the combustion chamber and let combustion gases slip into the crankcase. Common signs include blue smoke from the exhaust, steady oil consumption with no visible leak, low or uneven compression and heavy blow-by from the oil filler or PCV system.
Worn valve guides and seals can also burn oil. A compression test followed by a wet test or a leak-down test helps show whether the rings or the valves are the problem.
Choosing the right ring set
Ring sets are matched to bore size, piston design and ring thickness. Standard sets suit cylinders that are within service limits. If the block is bored oversize, you need rings that match the new bore. The sets listed here are standard size, not oversize.
Check the fitment table for your engine, and confirm bore size with your machine shop if the engine has been rebuilt before. A full set covers every cylinder.
Installation tips
Check the end gap of each ring in its own cylinder and compare it with the spec in the instructions. Install rings with the marked side facing up, and stagger the gaps as directed. A ring expander helps avoid twisting or breaking rings.
Cylinders usually need honing so new rings can seat. Use a ring compressor to slide pistons in, and expect the rings to finish seating over the first several hundred miles.
Piston Ring Set questions
Can I replace piston rings without removing the engine?
On some engines it is possible by removing the head and oil pan, but it is a major job. Cylinder condition, honing and bearing checks often make an engine-out rebuild the better approach.
Do I need to hone the cylinders for new rings?
Usually yes. Honing creates a crosshatch pattern that helps new rings seat and hold oil. Check the cylinders for taper and out of round first, since worn bores may need machining.
What does piston ring end gap mean?
End gap is the space between the two ends of a ring when it sits in the cylinder. Too little gap can make the ends touch when hot. Too much can increase blow-by. Measure it with a feeler gauge.