These driveshafts have been balanced as identified by the weights welded to the OD. This is a feature that you need to keep track of as a regular course of maintenance. If the weights come off, this can and will lead to a vibration that could be difficult to diagnose if you are not keeping track of the weights as part of your regular pre- and post-race inspections. Not all balance weights look the same; some are round and some are square or rectangular. So the weights on your driveshaft could be different. Be aware and alert, keeping a watchful eye on the weights.
Keeping the universal joints well greased (above and right) is a simple part of the regular pre-race maintenance program. It takes about three minutes to do both ends, and the cost is almost nothing. Make sure the universal joints on your racer are equipped with a zerk fitting so you can easily apply fresh grease. Many of the newer cars do not have this feature. Most heavy-duty universal joints are equipped with zerk fittings. If the universal joints on your car don't have this capability, replace them and install universal fittings that allow the application of grease without disassembly.
This universal joint is covered with rust, which is not always a result of poor maintenance. It's often a result of racing in the dirt. The tracks are wet and the universals are not in the most protected area. Another issue is the cleaning process itself, as repeated cleaning with pressure washers can drive water deep into the furthest reaches of the car, and the driveshaft is not immune to this type of damage. Pressure washers are not the enemy here. Rather, it is the failure to remove the driveshaft after washing so that all of the residual water and dirt can be cleared. Dirt racers have a unique problem that requires a bit more teardown as part of the normal maintenance program.