I had a tuning box on my previous FRL 2 for three years no problems and loved the car . Prior to exchanging it for a 12 sd4 I took the box off and found a massive difference in that the car was noisier and the drive not as smooth in fact it felt like a different car.
I have had the box reprogrammed for the SD4 and on a recent motorway trip with cruise set at the legal limit achieved 43mpg over 109 using the fill up method. My ave mileage on the computer is 34.2 but most of my mileage is around town and the car has only done 2.5k miles.
I do not want a flying machine as I am def not a boy racer but really like a smooth relaxing drive that I believe the box gives you. To support this I would point out that my previous 08 did not need new shoes until 34k miles whereas my son who has a 10 plate needed them after 15k miles
I am not an expert on engines or transmission systems but surely if you are happy to drive well below the limit that a car is capable of then there should not be a problem as a box is only making the drive smoother and in my opinion causing less stress to the car. Fuji White GS 12 privacy glass leather retrim

makes sense brian. drive a car with mechanical sympathy and it will last much better, However like wives , engines do need a good thrashing occasionally or they get lazy At work
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