i was running dieselsites coolant by-pass kit for over 5 years. It now sits on the shelf....but not because it didn't work. It did work. But after i had flushed the coolant system two years ago and added ELC coolant and changed the filter on the by-pass kit a few times after....the filter was absolutly clean each time. I see no need to have one on my truck anymore....it did the job and now i'm giving it to a buddy to use. The IPR kit looks nice, but wish it came out when i purchased my dieselsite kit.