I was going to get a custom steel chrome moley D shaft after i finish up my 9" upgrade, but i was surprized when i was told to go Aluminum from a reputable vendor, because he told me that i'll more then likely have Vibration issues with a steel unit , i'm not having any issues with my Stock steel unit, its in a 97 M6, but its really rusty (pitted), plus i'm sure it'll be about an 1" too short, but after hearing this, now i'm confused, so what do i do? I really want the steel because i know they are stronger.

 

I've got the Denny's NR shaft; which is Chromoly Steel, and have NO vibration issues.

The issues come in with what is called Resonant Frequencies; basically the frequency that the shaft naturally vibrates at. Aluminum shafts have a higher Natural Frequency than Steel shafts. That is why he said that.

If you have a properly balanced (High-speed balanced, not low-speed balance like a lot of places do), then neither shaft should vibrate when it's used. The steel shaft IS stronger, hands down. I know Denny's high-speed balances all of his shafts.

What vendor if I may ask recommended the AL shaft? And Personally, I'd just order a Dennys NR shaft if you're wanting to upgrade; Lifetime guaranteed, if you break the shaft (not the yokes) he'll build another for free.

 

Yeah, I have a Denny's nitrous ready driveshaft too, don't buy anything else.