[icingdeath88]

Originally Posted by jetboy

During urban driving, is D the better option or maybe 2 or 3?

3. The final drive gearing on the VTD 4EATs is different from the USDM ones, but here the problem is 4th gear, at low RPMs results in too low of line pressure to hold it in gear properly. So, there is a constant slip, grab, slip, grab, which you can't even notice. So even though it will shift into 4th at really low speeds, like 35mph, it's not good for it. Keep it in 3 until like 50mph, then shift to D. Because your trans is 3.7:1 final drive instead of 3.54, the speeds might be a bit different, but that's the idea. Also, the torque converter will lock up (in 4th) at anything above 50 mph if you're maintaining a pretty steady speed. This is good for reducing wear/operating temps.

Originally Posted by jetboy

Is it better to actively use manual mode in fluctuating situations or let it run itself?

Don't bother messing with manual mode, it's almost entirely useless. The only use I've heard of is when there's snow/ice, you can use 2nd or 3rd to avoid spinning the tires. The switched power mode mod is worth doing.

I thought the extra water pump line on the Euro cars was for an oil cooler for the engine? If it's for the trans, that's good, but I'd double check that.