Absolutely! In fact it is strongly suggested that if a u-joint has a fitting in between the caps, it needs to be positioned so that when under load with the driveshaft, the fitting needs to be under compression. Otherwise, the fitting hole is a prime location for a crack to start if the driveshaft tries to spread the u-joint caps because of the orientation. The cross drilling inside also weakens it over a solid with grease only in the caps.