Mineral VR-1 will do well. Since cost is a concern, check out Mobil1 15W-50 and FS 0W-40 from Walmart in 5 quart containers. You can get two shipped for free. Last time I checked they were about $25 each. The 15W-50 has lots of ZDDP, and the 0W-40 has just a bit less, but still enough for all but the most extreme spring pressures. The 0W-40 meets the most stringent Euro car specs from Porsche, MB, VW-Audi...
