Originally Posted by GTyankee
i have a flutter type noise right at 37 to 42 MPH, i assume that it is right at the torque converter lock up point, where the computer is starting to decide whether to stay in 5th gear or shift down to 4th while driving on level ground.
I believe that between converter lock up, MDS, & Fuel Saver/ECO mode, it causes the fluttering noise, going from 8 cylinder to 4 cylinder & back & forth,
luckily i don't hear it often, as our towns speed limits are 35 & 40 mph, except in school zones, if i have to drive in the city of San Diego, i just put the trans in 4th
That's interesting that you mentioned 37 mph. While the engineer was testing my truck, he noticed that the transmission at times would go into overdrive right at 37 mph. I was told by the service manager that the engineer noted that this was way too slow of a speed for the torque converter to lock-up, thus causing the engine lagg/vibration/noise.