Hi can you put a higher gas grade in a 2014 ford focus SE? I have been using regular and someone told me that it may help with the shuddering of my engine.

Premium only burns hotter if you have a high compression engine. Putting premium in an engine designed for regular is a waste of money. If your car pings a lot it can be worth going to a higher octane gas. Try a tank of premium or mid grade gas and see if your car runs better or not, you have nothing to lose but a couple of dollars.

Contrary to conventional understanding, the octane rating of the fuel that you put into the tank of your vehicle is literally zero indication of the quality of fuel that goes into it. The octane rating that is recommended for your vehicle is what you should be using. Going to a lower rating will lead to a "knock" or "ping" over time, and going to a higher octane than recommended by the manufacturer is both a waste of time, money, and can actually cause a slight reduction in performance. The rating has to do with the amount of time it takes for the fuel to burn inside the engine. A lower octane will burn too fast and essentially create a "shock" to the piston which causes the knock or ping. Going to a higher octane means that the fuel will burn more slowly, causing less pressure to push the piston and subsequently, the vehicle. This can produce a reduction in acceleration, and may reduce mpg as you may apply more throttle to compensate for the slight (although relatively unnoticeable) performance. With that being said, if there is a knock or ping when filling up with the recommended octane rating, then I would suggest getting the issue looked at by a mechanic. Going to a higher octane may reduce the knock or ping for a while, but if there's damage to the engine, continuing to use it with a higher octane will only exacerbate the issue until you end up with the knock or ping even when filling up with the higher octane. Now, that being said, as far as the skipping of the gears under acceleration and turning, this is a big concern for those that aren't quite familiar with how the new semi-automatic transmission works in the Focus. Without boring you with extensive details, which I'll be honest, I don't even fully understand myself, the transmission is set up like a manual from the functional side, but an automatic from the drivers perspective. So what you're feeling is the same effects as if there was a seasoned, non-professional driver using a manual transmission. When using more throttle, the transmission will feel like it's shifting smoother, but you'll still have the lag between gears, most noticeably between first and second. This is the normal function and is of no concern to Ford or it's engineers. In fact you may (or may not) have noticed that when stopped on a relatively steep incline, releasing your foot off the brake will hold the car steady for a second or two, but then release causing the car to roll backwards. There have been a number of claims under the California Lemon Law as a result, but none have been awarded as the claims were based solely on a dislike of the normal function of the transmission. Wow... this turned out to be really long winded. Hopefully you grabbed a beer or something halfway through and finished that before this... Otherwise it's warm. Sorry.

I have used regular in my regular gas cars for several decades and have never had a fuel system problem either. Premium is no better or worse in regards to fuel systems. It is necessary when you have a high compression engine though. I went over 100,000 on the original set of plugs in my Ford and never ever did I use premium. If it works for you great but in my opinion you are wasting money but it is your money, not mine.

Premium is a misnomer. The only difference in gasoline grades is higher octane gas has more molecules with chains of 8 carbon atoms instead of 7 carbon atoms. Longer chains have more energy due to more chemical bonds and also evaporate at a higher temperature. A little basic chemistry lesson.

The 2014 have issues with shifting and transmission problems I just bought one three days ago and thought it felt weird and now I'm finding on line it's a known issue and there have been recalls as well Google it there's a ton of information regarding your issue

the duel clutch automatic is dodgy in the 2012,2013 focus.