Tranny double-shifting from OD

[midnightrider13]

New here, and need some advice on my transmission. I bought a 2001 F-350 last fall to haul campers and camp trailers with. Since the day I bought it, it has been double shifting - when I turn off the OD, or when I kick down with the foot feed, the tranny shifts down two gears, is there for a second, second and a half, and then gives me the right gear. I have put 40,000 miles on it in the last 3 1/2 months, and it has done it every time. I took it in to my local speed shop and had a 50 hp flash done, and re-did the shift points, no help. I'm just about to lose my mind, because now the tranny fluid is beginning to smell slightly burned, but is still bright pink. I think it is from sliding in and out of that lower gear when it down shifts. The tranny shifts exceptionally well, with no lag or slip between gears, except when it double shifts. When it does that, it hits the lower gear, then kind of slides up to the right gear. Anybody ever heard of this? I sure don't want to pay for a new tranny or rebuild this one if I can avoid it. Thanks!

[JSchuricht]

What RPM's are you seeing when it dose this? Reason I ask is it sounds like perhaps it is downshifting and unlocking the converter, then relocking it giving the impression of another shift. Either way, your best bet is to hook up a scan tool and see what the transmission is doing.

[midnightrider13]

Thanks for the reply...
It does it at any RPM, it will do it if I don't catch it and it kicks down on cruise at 65 mph, running around 2200/2250 and redline when it shifts, and it will do it when I'm just cruising around 45 or so. It doesn't seem to make any difference what the speed is, what the RPM's are, or weather I'm loaded or empty. I'm intrigued by the converter locking issue you mention, because it does seem like there is an extra gear in there. From the door code, I think I have the 4R100 4 speed auto. It does seem like there is an extra shift in there. If the converter is unlocking, then locking again, is there a programming fix for that, or is that mechanical - and what kind of scan tool would I use? Thanks!