1997 E420 722.6 trans delay in engagement

[HerbPhillips]

Gentlemen,

Stumped on a 1997 E420. Car has 114 k. Trans had bad flared, delayed shift through all gears, and would sometimes bump into neutral on hard upshift on expressway.

dropped pan, no particles, beautiful orig fluid. Replaced valve body w/MB reman and new conductor plate, replaced fluid in pan and filter. Reset Adaptation. Car now shifts beautifully through all gears BUT....

New problem is delay in engaging reverse or drive from park. Car takes 2-3 seconds to engage either reverse or drive....Fluid level is fine...Any ideas?

No stored codes.

Herbert Phillips
Memphis,Tn

[C32AMG]

The electronic control module is married to the valve body; it’s a life time commitment. Your TCM is calibrated to the old valve body, they are a SET. You need a new TCM.

[HerbPhillips]

I asked the parts dept and they said no new tcm is needed. Are you sure?

[C32AMG]

If the TCM and valve body are combined incorrectly, the switching operation is always a delayed engagement in to R or D.

[HerbPhillips]

Meaning, can I buy one from a salvage yard?

Or does it have to be new?

Any idea of approx cost?

[C32AMG]

If you found a correctly coded TCM from exactly the same model vehicle, maybe; But the same question still remains; does it have the correct software to match you updated valve body.


Ask if they can reflash the TCM with the latest software to support the updated valve body part number.