WELL ACTUALLY THE PISTONS ARE SMALLER BY ALLMOST 3/4 OF AN INCH IN TOTAL HEIGHT ,BUT THEY ARE THE SAME DIA THE DIFF IS IN THE STROKE, THEY USE THE SAME RINGS AS THE 3.2 THIS APPLIES TO ALL 98 AND LATER ENGS EXCEPT THE 3.5 DI ENG , AND YES YOU COULD SWAP IN A 3.5 CRANK , RODS AND PISTONS , RINGS AND A SET OF BEARINGS AND BE OVER 3000 DOLLARS OR SPEND AROUND 4 AND GET A BRAND NEW READY TO DROP IN ENG ... NOW YOUR RESEARCH IS DONE JERRY