The smudging issue is a direct symptom of a failing fuser. The fuser assembly uses heat and pressure to permanently bond the toner powder to the paper. When it malfunctions or reaches the end of its service life, it cannot apply sufficient heat, causing the toner to remain unfused and smudge easily upon touch.

The paper jam, occurring specifically when printing legal-sized documents from Tray 3, points to worn-out rollers in that particular tray. The pickup and feed rollers are responsible for grabbing a single sheet of paper and feeding it into the printer. When they become worn and lose their grip, they fail to feed the paper correctly, resulting in jams before the printing process begins. Replacing these two specific components resolves both reported issues.

HP Inc. (2023). HP LaserJet Pro - Resolving Print Quality Issues. HP Customer Support. In the section "Toner smears or does not stay on the paper (unfused)," the primary recommended solution is to check and replace the fuser if it is near the end of its service life or damaged. The document also links paper jams from a specific tray to issues with the paper pickup rollers for that tray.

Brooks, C. J. (2022). A+ Guide to IT Technical Support (11th ed.). Cengage Learning. In Chapter 15, "Supporting Printers," the laser printing process is detailed. The "Fusing" step (Step 6) explains that heat and pressure are applied to melt the toner onto the page. The troubleshooting section confirms that unfused toner (smudging) is caused by a fuser problem. The same chapter identifies worn pickup rollers as the primary cause of paper failing to feed from a specific tray.

Meyers, M. (2022). Mike Meyers' CompTIA A+ Certification Passport (7th ed.). McGraw-Hill. Chapter 14, "Printers and Multifunction Devices," describes common printer problems. It explicitly states, "If the toner rubs off the paper too easily, you have a fuser problem." For paper handling issues, it identifies worn-out pickup rollers as the cause for a printer failing to pick up paper from a tray.