October 30: LEMON manuals on a temporary server, it is slow and having issues, download the manuals you need! Later in November we will switch back to the fast server.

Diagnostic Aids

Check all connections, especially those at transmission pass-thru connector. Fault may be an internal transmission problem.

Fig 1: Code 87 Schematic (4.3L) High Gear Ratio Error

Fig 2: Code 87 Flow Chart (4.3L) High Gear Ratio Error