With a load it lugged on hills and I downshifted fairly often. I sold it to a friend who commuted on a highway. He kept the old axle for the MPG. But I think that works the engine too much ie. you're often out of the good RPM range.



Boy are you right. It's what I'm fighting with right now. It doesn't help that my other 240 has the 3.73 axle and I can feel the difference in drivability. I commute in Northern VA, the metro DC suburbs, and never get more than 30 seconds at a stretch over 40mph. Ugh.

My OD is wired through a spare emergency flasher switch. It's the only stock 240 switch that can light up the OD arrow on the gauge cluster when you cut power to the solenoid. Actually, in my wagon with the manual-to-auto swap, I used a seat heater switch, and I use it OFTEN to keep the rpms in the right range for fighting stop and go traffic.

Time for a 3.73 rear, but not sure if I should swap the ring and pinion or the whole rear end.

The reason for the relay is not as much current through the switch as it is affording alternate action hand on the shifter control and default OD=on when the car is started. The harness is not there on M47 cars.

There's one more gotcha on the "Jorrell" swap, when applied to an 89. There's a violet wire at the 9-pin cabin harness to LH harness junction which selects the ECU function for shift indicator. This shares wiring with the cluster's OD OFF indicator, so if not unpinned, gets a resistor inside the ECU smoking hot. But this is only a problem if the auto overdrive relay harness is installed.

--
Art Benstein near Baltimore

If life gives you llamas, make llamanade.