A340E problem partially solved but still looking for help

mirage83

New Member
Mar 21, 2008
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Georgia
The problem I've been working to solve is my transmission being overly fond of L1. While driving around in Drive or Overdrive it will suddenly and without any prompting drop into L1, at which point I have two options... let my speed fall off to around 15 mph when 1st gear re-engages and allows me to accelerate again, or popping the transmission into Neutral and then back into drive which also lets me accelerate and/or continue driving normally.

From the error codes I knew I had a shorted O/D shift solenoid, so I replaced all 3 in the transmission with new ones. Shifts great, but still has the problem with dropping into L1. Next I tried swapping out the ECT to see if there was any difference. Nope, still likes L1. Yesterday I disconnected the ECT entirely and drove while shifting manually from L1 to L2 to Drive. Shifted perfectly, but STILL dropped into L1 unexpectedly. It doesn't do it EVERY time I drive it, but often enough to convince me that it really needs taking care of.

So, from all that I think I've narrowed down the trouble area to something about the transmission itself rather than the computer shift-controller (or the shift solenoids which I've already replaced). As I'm not a transmission guru by any means I'm now completely out of my element and am hoping that someone on here with more experience with this transmission and maybe even this kind of problem can give me some guidance.

Thanks in advance everyone.