I have a 65 12 bolt rear end that I am going to get rebuilt this week. I have been told that the standard metal axles on 12 bolts are notorious for failing/leaking. The place that I have been recommended to go (J&S Gear in Huntington Beach) wants to put in billet axles and claims they will last much longer and make the rear end stronger too.

I am not building a race car by any means. I still am not even sure if I am going to stay with small block or go with a big block although I am leaning toward a big block.

Help please with what I should do......

If you have any knowledge of how axles are made, then a billet axle would be a very expensive joke. Axles tend to be made from forgings which are subsequently extruded to length. And that is a process that works very well. So someone is blowing smoke at you.

Moser 12 bolt replacement axles will do you just fine. The stock axles tapper and they can and will break with enough power and traction. The moser axles are straight, non tappered and are stronger than stock axles.

If this is a street car then the stock axles will be fine, as long as they are still good. If the axles are worn where the bearings run on them then you need to replace them. After market axles are not tapered like the original axles are. They are stronger too. Just be sure that you are getting good quality axles. Some of the cheap replacements are not heat treated. I have installed many sets of Moser and Yukon axles with no problems reported.