 This is an update on my previous posts. Recently at 28000 miles I noticed the oil pressure light was flashing in my Routan. After inspecting the dipstick I was surprised to see that the car had very little oil, so I ended up adding 2.5 quarts of 5W-20 oil. I was surprised because I have never missed any of my scheduled maintenance. When I took the car to the dealer they said that they have seen this issue with these vans. And the recommendation was to check the oil level every 3000 miles. They said these vans burn oil in average 1 quart every 3000 miles. For your info, I have changed my engine oil in average every 5500 miles when the light had indicated that it is time to do so.