Is this a transmission or some other problem? (Vehicle slowing down at a faster rate)

[dsdelli]

I have a 2014 Ford Expedition XLT 4WD. It has 65,000 miles and I have owned it 2 years and driven it for 14,000 miles. The following event happened today for the first time. i was driving about 55 mph, took my foot off the gas pedal to make a left turn. Instead of slowing down "normally," my Expedition slowed down as if the transmission downshifted into a lower gear and the vehicle slowed down MUCH faster than usual. I tested this several more times and each time, my vehicle slowed down at a much more aggressive rate than it has in the past. It was like I downshifted into a much lower gear when taking my foot off the gas pedal and the transmission was slowing down the car. I sometimes shift into a lower gear while driving down a mountain to let the transmission slow me down instead of constantly breaking. Everything else seemed normal. No noises, clanking, can't hear anything unusual, etc.

Does anyone have an idea of what is going on and what needs to be fixed? Thank you in advance!!!

 

[99WhiteC5Coupe]

I have a 2014 Ford Expedition XLT 4WD. It has 65,000 miles and I have owned it 2 years and driven it for 14,000 miles. The following event happened today for the first time. i was driving about 55 mph, took my foot off the gas pedal to make a left turn. Instead of slowing down "normally," my Expedition slowed down as if the transmission downshifted into a lower gear and the vehicle slowed down MUCH faster than usual. I tested this several more times and each time, my vehicle slowed down at a much more aggressive rate than it has in the past. It was like I downshifted into a much lower gear when taking my foot off the gas pedal and the transmission was slowing down the car. I sometimes shift into a lower gear while driving down a mountain to let the transmission slow me down instead of constantly breaking. Everything else seemed normal. No noises, clanking, can't hear anything unusual, etc.

Does anyone have an idea of what is going on and what needs to be fixed? Thank you in advance!!!

Have you inadvertently turned on the transmission tow-haul mode?

 

[dsdelli]

First, thank you for your reply! No, that isn't the case. I can turn that on and the dash lights indicate it is turned on, and then I can turn it off. Good observation though. I will add that it acts like it is supposed to be slowing down the vehicle instead of some kind of problem. I was going to take it on a trip and it happened right before leaving so i didn't have a lot of time to troubleshoot. According to the owners manual, it has a feature called "Adaptive Transmission" and I wondered if that was causing the issue. I disconnected the battery and that causes this feature to reset and it seemed to lessen the situation but I wasn't certain. I just didn't have time to troubleshoot for an extended time. thanks again!