Just get the OEM bellows adhesive. It's so much better than the sierra stuff.
I have used both. Our supplier sent Sierra the last time and I tried it on a couple of orings. Threw it in the dumpster. Now have OEM only.
I've successfully used Permatex weather strip adhesive multiple times. Use gloves when applying it - it is fairly resistant to cleaning off skin. You can pick it up at most any auto parts store for about $3 for a 2 oz tube.
I had a shift cable bellows leaking and didn't have time to tear the outdrive out so I used some Permatex Right Stuff. It stopped the leak until I had the chance to tear it all down. When I pulled the shift cable and boot out, the sealer that I put in it created a plug that was not easy to get out. This stuff seals great. I am an Auto Technician and we use this stuff in the shop for gaskets. It is the best that I have seen. It is expensive but it does the job great and we have plenty around the shop.
