almost all cars with cam chains DO have tensioners. and many makes of cars do have issues with the things. many use belts to drive the cams - those fail too. quite a few other bike boards are filled with issues regarding chain tensioners, cam problems, clutch problems. years ago i had a gold wing that needed one new piston - the smallest part available was a complete rotating assy to get a piston. in the 70's there were always guys complaining about the cam drive on there pontiacs going south and bending valves. the plastic gears would go south, so then they put in steel aftermarket sprockets and the chains would go south. the only hot rods that dont have cam chain problems are the ones with small cams or zero miles. high mile cars got new cam chains on a regular basis. remember those old cars would be complete junk at 100k miles - trucks would do 100k and then die, but cars, 60k and overhaul... modern belt drive cams need new belts before 80k or they grenade the whole engine.
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