P1740, OD on-off, some slippage on 2000 B350
 

Got P1740 code and van continues to drive normally on surface streets.

Some slippage going up very steep, short hill from standstill.

Freeway driving at about 65mph, OD kicks in for maybe 20 miles, then off, then on again. Stopped for 15 minutes and OD off for remainder of 200 mile return home.

Fluid pink and at max mark in neutral . No smell, no dirt.

Bringing it to tranny shop tomorrow. Questions:

1. What's your guesss: Torque converter or OD solenoid?

2. What else should tranny mechanic do while it's in for service?

If the trans gets hot, PCM will drop out of O/D. Of course, that happens before the trans temp light is triggered. Trick would be, see if temp is getting too high when the condition presents itself.....

No error code showing heat or other dashboard light. Overheating O/D might actually go in favor to overfilling so 4th gear gets some fluid. (Argument from other message.)

Overfilling has never been a good idea. Start whipping air into the fluid, (which is what happens when you overfill....) and things go south quickly.

Overtemp won't set a code. And the PCM will kick out of o/d before the trans gets hot enough to turn on the temp light.... only way to catch that, is to be watching trans temp when it drops out of o/d.