Couple weeks ago I noticed a small oil leak from the pulley shaft, so I decided to do the seal replacement by my friend Mikey. There is an inner and outer seal so I ordered both from Supercharger Rebuilds, and Mike took the head unit apart. We were amazed how simple these units are....couple bearings...shaft gear and seals.....not too much! On inspection he noted that the bearings were not smooth as could be, so I figured might as welll replace them too. Called Todd at Supercharger Rebuilds again and got the 2 new bearings for a T-trim. When Mike got them he noticed that they were too big....so I called Todd back and he appologized because aparently Vortech sized the bearings down on later units. Wanted to say Todd was great to deal with a good guy,he sent the bearings out next day and we got them in. Blower is smooth and tight! Thank You !