Complaint:
2003 and up Dodge vehicles equipped with the diesel engine and the 48RE transmission may have a complaint of a partial engine stall at a stop followed by a sudden engine rpm increase. This sudden engine rpm increase may be difficult to overcome with the vehicles brakes.
Once the vehicle takes off it may be also noted that the upshifts are firmer than normal as the Torque Converter Clutch is On. Note: this complaint does not include a complaint of stalling in both Drive and Reverse, as this is typically caused by a defective torque converter, a restricted cooler and or a stuck TCC Switch Valve.
Cause:
The cause may be, that the Torque Converter Clutch solenoid, located in Figure 1, is partially restricted, causing the Lock-up valve and Lock-up switch valve to stroke applying the Torque Converter Clutch. The 48RE transmission unlike the 46/47RE has 1st gear TCC capability, and when the solenoid is mechanically restricted it will cause the TCC to apply in 1st gear. The ECM, on these Diesel applications can bring engine rpm up when the TCC is applied to keep the engine from stalling.
Note: Customers that have had this complaint have found that if the vehicle is hard to stop, pushing the selector in to neutral, with the brake depressed will stop the ECM from driving up the engine rpm and will allow the vehicle to stop much easier.
Correction:
To correct this condition, replace the Lock-up and Overdrive solenoid assembly, as they are assembled together.
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