I have a 2012 Sport S JKU. I seem to hit a lull in acceleration between 40 and 50 mph. If I hit the gas hard it's not a problem, it seems more apparent when driving in the city, 30-35 mph, and slowly increasing speed. It feels as though it's "stuck" in a higher gear and not down shifting to allow for acceleration.

Has anyone else experienced this issue? If it's a normal occurrence I don't want to waste my time and or my dealers time looking into it.

- Dave

 

In my experience, this transmission is not particularly crisp shifting. Other cars are much more sure about their upshifts, even this transmission in other Mopar products. Having said that, it may be by design since having the JK pop into a higher gear when wheeling could be detrimental. Maybe there is more play/slop in the torque converter to allow for mellower shifts. I would ask the dealer, but I don't feel like taking the time to do it. If you do, please report back with what they say.

 

Pull the negative battery cable off for a couple minutes and then reconnect. This should put the transmission powertrain module back in learn mode. Then drive it as aggressive as you'd like it to shift while it learns.

 

I will just tap the shifter down manually if I need more or want to save fuel. It's a nice option to have on the 12 auto.

 

Many 2012 drivers say they feel a 'dead' spot between 1,000 - 1,500 rpm. Someone said there was a computer update to change the shift points. When I called my dealer they checked and couldn't find any for mine. They said it can take up to 5,000 miles for the computer to learn your individual driving style to set how/when the transmission shifts.

 

ok, I'll contact my dealer after the holidays. That's exactly where the RPM's lay when accelerating between 30 and 40.

 

Any updates? Mines doing the exact same thing. Even my wife noticed. Guess ill try disc the battery first.