Own a Dewalt 3750 pressure washer that I use on a monthly basis to wash out concrete, concrete pavers, walls, etc. I do NOT have the manual but did an online search on how to replace the oil and which kind of oil to use. DP70 pump oil or 30 weight oil is recommended. I cannot find a local store within 20 miles of where I live that carries Dp70 oil by DEWALT so my next option is the 30 weight oil. Now the problem is that on the manual 30 weight is shown as (30w). Does that mean I can use 5w-30, 10w-30 or am I supposed to use 30 weight meaning SAE 30. I think its SAE 30 but I'm open to recommendations from forum members that have pressure washers or experience with pressure washers. Thanks