No, diesel was run through it and no problems. Rod Jarsma from Michigan installed it on My pulling truck before I purchased it from him a while back. I took it off due to a sponsorship. You can go to SX web site and read up on them. The site will tell you to not run low sulfur diesel through it. I went there to read up on it and it told me a lot about the pump and filter. Farm diesel I believe has the higher sulfur in it and works well. But I could be wrong about that.