Installed on a 2000 Tacoma 3.4L with rear axle access. It removed about 90% of the hum from the old crappy straight through muffler. This muffler was easy to assemble (took about an hour to weld), but it depended entirely on your car and your skills. Find the correct flow direction for the muffler. It wasn't on the muffler, nor on the box, nor in the documentation, nor on the website, nowhere. I installed it with a center channel forward (upstream) and an offset channel aft (downstream). Sounds good, not as quiet as we'd like for chasing tracks, but a nice raspy sound when you hit the gas. It's about 100 miles and I live in a relatively dry climate so I expect this to be a long time. I will update this if anything changes.