Originally Posted By: Panzerman
I just changed my oil yesterday and used Castrol gtX 5w20 and it was nice clear yellow. Castrol will range and change from yellow to amber and sometimes just relly dark brown. I have never seen Castrol or any new oil(except Arco Graphite) come out of the bottle Grey. You confirmed that it was grey by putting it in a clear bottle. I would definetely drain it and change it, especially since it isnt your car, but the motherinlaw. Castrol GTX is a first class oil. I think you may be the victim of a scoundral, returning used oil or some foul play. Castrol GTX should not be Grey.
I have an open qt of Castrol GTX 5W20 as I recently changed the oil/filter in my daughters mazda3(4.5qts). It too looks golden-ish!
I just changed my oil yesterday and used Castrol gtX 5w20 and it was nice clear yellow. Castrol will range and change from yellow to amber and sometimes just relly dark brown. I have never seen Castrol or any new oil(except Arco Graphite) come out of the bottle Grey. You confirmed that it was grey by putting it in a clear bottle. I would definetely drain it and change it, especially since it isnt your car, but the motherinlaw. Castrol GTX is a first class oil. I think you may be the victim of a scoundral, returning used oil or some foul play. Castrol GTX should not be Grey.
I have an open qt of Castrol GTX 5W20 as I recently changed the oil/filter in my daughters mazda3(4.5qts). It too looks golden-ish!
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