I have a Diesel Duster 85 PS. So here is the deal. 1. I upshift at 2K RPM most of the times. 2. I drive at 80kmph in 5th gear mostly, but I keep varying the RPM till 2.5k rpm to reach 100 and then come down to 80. 3. Also, I noticed a strange phenomenon post 500km mark on ODO. Earlier I saw engine doing 80kmph in 5th gear at 2k rpm, but now after 500Kms it does the same speed at same gear at 1850 rpm. Is this normal? Should be worried about this? Similar drop in rpm can be seen in lower gears too, except 1st I think. Will this speed gear rpm combo change further? Till when? 4. Also, when I stop at signals, I do not switch off the engine because I do not want to bring down the temp of the engine. Is this the right way? When should I switch off engine in stop go traffic? Any handy tips? 5. Another thing, when I move the gear in neutral waiting at a Red Signal, I noticed that during idling time there is rhythmic action engine takes and perhaps send tiny, very tiny amount of vibration to cabin. Mind you nothing moves an iota inside. Just that I can feel the feather light vibration while resting my hands on steering. This super minuscule vibration is rhythmic at interval of about 1.3 secs. is this normal? During driving this vibration goes away and I do not sense of feel any goddamn vibration inside. Please share your experiences.