Well yeah a CV joint is actually a double cardan .... without the rubber boot.
So we are all correct...
However If you walk into a jeep shop or 4WD shop and tell them you need a CV joint for your Jeep XJ front shaft they will laugh you out of the shop.
The commonly used terminology is double cardan joints for driveshafts and CV joints for front axles... especially front wheel drive cars and even VW bugs.
speaking of jeeps, some guys will use a double cardan joint on the back also along with a slip yoke eliminator... that way if you bust the rear shaft out in the woods you can use the front shaft in back.
double joint in back also helps with extreme driveshaft angles on lifted rigs.
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