Funny, I have a 2010 FX35 and experience the same issue. When going between 20-40 mph, I gradually and gently apply throttle and around 30 mph or so the rpm's drop to around 1k and it sputters. Sometimes it downshifts, then upshifts again. Almost like it's trying to go into 7th gear (overdrive) which brings rpm to 1k, then realizes it's too soon for OD, and drops back to 6th. Occasionally it goes back and forth between the 2 like it can't make up it's mind which gear to be in. Only really a problem in that range of 20-40 mph.
The dealer said they reflashed some things (not sure which exactly, sounded like computer for controlling throttle as well as transmission shifting), and I pick it up tonight. So I should know whether this fixed it or not.
Since mine is a 2010 and after I explained the symptoms, and they just reflashed it, there must have been a TSB or something with updated software for the 2010. So if anyone else experiences a problem on a 2010 or 2011 I'd suggest asking the dealer about it.
The dealer said they reflashed some things (not sure which exactly, sounded like computer for controlling throttle as well as transmission shifting), and I pick it up tonight. So I should know whether this fixed it or not.
Since mine is a 2010 and after I explained the symptoms, and they just reflashed it, there must have been a TSB or something with updated software for the 2010. So if anyone else experiences a problem on a 2010 or 2011 I'd suggest asking the dealer about it.