Here's a question, I just changed out the oil on my two front end loaders, and now have four empty 2.5 gallon jugs. I drained them out for three days over a strainer into a bucket, so they are completely empty. Would it be safe to now store synthetic oil in them? I have about 20 qts of 5-50 and about 10 quarts of 5-20, and figured I could consolidate the quart bottles into the larger 2.5 gallon jugs, that previously held 15-40 delvac. Your thoughts ?