It is actually banging back to second gear. That is "limp mode" to allow you to drive slowly to a repair shop without needing a tow truck. The place to start is by having a mechanic read and record the diagnostic fault codes in the transmission computer.
That computer performs electrical checks when you turn on the ignition switch. The fact the transmission shifts normally at first suggests the electrical circuits are okay, unless there is an intermittent connection. If it goes to limp mode during or right after an up-shift, it is more likely there is a mechanical problem inside the transmission. Worn clutch plates are the most common suspect. Along with reading fault codes. The scanner can display the "clutch volume index", (CVI). That is a set of four numbers indicating the volume of fluid it takes to apply each clutch pack. Based on those, an experienced mechanic can tell how much life is left in the clutch plates. Those will also verify if slipping clutch packs are the logical suspect.
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Tuesday, August 22nd, 2017 AT 4:27 PM
