You guys convinced me to slide out my 502 bumpstick in favor of a 503 when I slap on Lloyd's heads in about a month. I have the LT4 ED timing set that I installed new when I put in the 502 about 5 months ago. That was about 5K ago. When the cam is pulled, the set will probably have 6K on it at most. Do I need to replace anything? New gears? New chain? I want to do it right, but even just gears is expensive as hell for the ED stuff. Oh, I also have the oversized crank sprocket. Cool, thanks guys.
Don

 

How about dump your stock h20 pump go electric and do a cloyes roller chain. For the price of the Ex chain you can do them both and free a littel hp. Pump is $135 CSi or $185 for a Meizre and the cloyes chain is just around $75.

 

I would leave it in there.It should be like new still.If it worries you then a double roller should handle it,like said above.

 

Thanks guys. I'm set on sticking with the extreme duty because I like the reliability of the mechanical pump. At least if its going to fail, I'll get a fair warning. At such low mileage I'm not really worried about it, it's just that I've read several places ANYTIME you remove the timing set, at the least the gears should be replaced. I'm not sure if mileage played into that at all and I just want to be sure. Nothing like a timing chain snapping at 6K.