The universal joint cross-shaft needle bearing of the drive shaft should be lubricated with gear oil. However, it is generally found in automobile maintenance that the universal joint cross-shaft needle bearing of the transmission shaft is lubricated with calcium-based grease (commonly known as butter). Actually, this lubrication method is wrong, resulting in a large number of cross-shaft needle bearings. Early damage. In the disassembly, it can be clearly seen that the cross shaft journal presents a groove that is squeezed and pressed, and the journal and the needle are severely deficient in oil.
Why would such phenomenon happen? It is because the lubricating oil nozzle of the universal joint cross-shaft needle bearing is an ordinary grease fitting, which gives people an illusion that it has been generally lubricated with grease for a long time. In fact, it is very difficult to fill the butter bearing to the needle bearing with a grease gun from the nozzle.
When the maintenance is removed, the use of a forced method to apply butter to the needle and journal surfaces can also provide some lubrication, but for the lubrication of the cross-shaft needle bearing, the calcium-based grease is far less than the gear oil. Ok, the reason is:
a. The universal joint is subjected to a large torque and alternating load during work, and the oil film of the calcium-based grease is tough, and it is difficult to form a good oil film on the friction surface of the bearing and the journal.
b. The needle roller bearing of the universal joint cross shaft can only rotate in place during the work, can not rotate along the steel bowl and the cross journal, and the calcium-based grease has poor rolling property, so it cannot be formed immediately after the oil film is destroyed. New oil film.
c. Calcium-based grease is a mixture of oil and calcium soap. In use, due to the deterioration and evaporation of lubricating oil, the grease becomes a hard calcium soap. The calcium soap itself can not only play a lubricating role. Moreover, it also hinders the rolling of the needle on the journal, and there is no oil draining measure in the universal joint cross shaft. The deteriorated grease can neither be discharged, and the new oil is difficult to inject, thus greatly accelerating Wear of the cross-shaft needle roller bearing.
In order to change the wrong way of lubricating the universal joint cross-shaft needle bearing with butter instead of gear oil, the following maintenance methods are recommended to improve the service life of the universal joint cross-shaft needle bearing.
a. Remove the universal joint cross shaft needle roller bearing and thoroughly clean it. Remove all residual grease (can be boiled or put into gasoline for cleaning), then put it in gear oil for 2min~l0min, then it can be used. . In use, it should be noted that the new oil should be replaced in time after the car is wading. New oil should be replaced once between 2000km and 3500km. This method has been tested to extend the life of the universal joint cross-shaft needle bearing by a factor of two to three.
For more information and purchase please visit: https://www.supplyforever.com