Many thanks everyone. I will probably opt for a thicker oil on my next oil change. Is Mobil 1 20W-50W, thicker oil? What does the numbers mean .e.g. the higher the number, the thicker it is? My next question is, I use my 126 sparingly, probably 1k a year max, mostly driven in the summer or when it is dry. My last oil change was in July 2007 (used normal non-synthetic oil). Since that time, the car did just under 900 miles. On visual inspection, the oil is still like new (very clear). Seems like an odd question to ask but does the engine oil deteriorate? Do I still need to change oil as often even if the vehicle is used occassionally? Also, I probably need a thicker oil to reduce wear on the engine particularly when it does not get used very often.