The practicalities of lubrication and maintenance of the universal joint together with the frequencies for each procedure can be found in the beginning of the corresponding section. The needle roller bearings wear off and the presence of the wear is shown in the vibration of the transmission during operation, noise during acceleration and ultimately metallic squeaking grating and shrieking in cases of improper lubrication of the bearings. While the driveshaft is in position, a candidate should rotate it by hand in an effort to look for wear in the needle bearings when analyzing the rear universal joint, attempt to rotate the rear axle flange with one hand and the other should be on the front half coupling when analyzing the front universal joint. Vibration or motion about the driveshaft and the front half couplings and around the rear half couplings indicate the need for replacement. The other technique involves, using pry bar at the gap between the universal joint, and the driveshaft or flange, when the vehicle is engaged to a gear, exerting force radially and axially on the joint should should expose any signs of looseness. The final test of wear is trying to pick up the shaft and look or feel if there is any shifting of the yokes of the joints. If any of these conditions is present, it is required to replace the universal joints with new universal joints.