Why do I keep wearing out and/or breaking u-joints?
There are a number of reasons you might be having repeated problems with drive shafts or u-joints.
One is that your drive shaft and the shaft's components are just too small for the application. If you've got a Jeep with an LS motor, Dana 60s, and 42 inch tires but you're still running the stock size joints in your drive shaft, it is time to upgrade to something bigger.
Another common problem is over-flexing and binding. This could be because you have a lot of lift and the shaft is running at too steep of an angle under full suspension droop. Or, it could be because of axle wrap. Axle wrap is a very common problem with leaf spring vehicles that have a spring-over conversion. If you think the shaft is binding, look for marks where the yokes are making contact with one another.
The last cause we'll list is one that can be very tricky for most people to diagnose. It is a common problem and if you don't know know what you're looking for, you would never suspect it. Watch the video below for a full explanation.