Q: Transmission not going into reverse.

Hi there. The two problems you just described are two of the most common issues that plagued the Ford Explorer since the 2000 model year. The first problem of transmission is caused by the transmission case leaking internal pressure and the overrunning clutch breaks causing no reverse. The only fix is to replace the transmission assembly with a remanufactured transmission. The second issue of engine cam chain noise is that the timing chain guides have fallen apart. The fix is to replace all the timing chain guides with a new style. This is a major engine repair that takes special tools to do properly. Another issue is that sometimes the broken pieces fall into the oil pan and the engine will have to be removed to do a complete repair. Sometimes it costs less to have a remanufactured engine put in, instead of trying to repair the noise in these engines. Schedule an inspection of your transmission before making any decisions