Model Focus: HP LaserJet P3005, M3027MFP, M3035MFP Problem - Grinding. Most often after replacing the fuser. Troubleshooting: A grinding problem can occur with normal printing; however, most of the time it happens after changing out the fuser assembly. After replacing the fuser you may hear a rumbling sound from the rear side of the printer. This rumbling, or grinding, is due to the newly replaced gears working with the worn fuser drive gears. When the printer is turned on, the fuser and exit rollers spin at a very slow speed for about 2 seconds then run at full speed for about 5 seconds. The second faster speed is usually when you will notice the noise starts. The main drive assembly initially turns the fuser, and then the fuser drive assembly engages the fuser at full speed using the set of four fuser drive gears. To eliminate any grinding noise, replace the worn fuser drive gears. Note: When replacing the plastic Thrust Stopper Clip (RC2-0657), be sure to have the longer part pointing down. Failure to do so will cause paper to jam at the fuser or to jam when printing in duplex mode. *This Tech Tip is contributed by Laser Pros. Visit their website www.LaserPros.com or email any question to marketing@laserpros.com.