Got a 2002 Land Rover Discovery II with 133k miles, low oil pressure. Too long a story to type here but suffice it to say that I have checked it mechanically and the cost to repair the mechanical bits to correct the oil pressure is more than the truck is worth - however it is my daughters transportation and I would like to avoid buying another one as long as possible. Currently have Valvoline High Mileage 20w50 in it, previously tried Diesel 15w40 with no change in oil pressure (7 at idle, around 30 at 2500 rpm, mechanical gauge). We live in South Carolina so low temperature days are few and far between - however I am reluctant to dump simple viscosity thickener in due to additive dilution. Seems the discontinued Valvoline Syntec Oil Treatment was well thought of from a additive and viscosity modifier standpoint but no longer available. Looking for some UOA's that show effects of currently available treatments - mostly looking for high viscosity at 210 F without significantly higher viscosity at 40 f (or room temp). However I can't seem to find any UOA's with treatments included - anyone have any idea why?