I've been looking at external dampeners lately, and I've heard that the 6.7 OEM dampener will work on the 5.9, and they are as good as the expensive aftermarkets.

Any word on this?

 

I hear they are. You will need to change one other pulley. I think it is for the fan.

 

why not use the one that's designed for the engine?

 

The OEM 5.9 dampener isn't the best in the world, they start to crack after 100k. There are some really good aftermarket ones, but from what I hear, the OEM for the 6.7 is almost identical to the aftermarket ones for the 5.9 and much cheaper.

 

And the OEM 6.7L damper allows you to change your belt without having to pull extra crap off. I have it on my 5.9.