Can someone shed some light on the difference between 'Aluminized Steel' & '409 Stainless Steel' as the preferred material for a new tru-dual exhaust system?

Stainless steel is just that...a grade of stainless steel, where aluminized is essentially mild steel that all exhaust systems used to be made out of that is aluminum coated for rust and heat resistance.

Years ago most or all cars came with exhausts of simply mild steel. It was easy to bend, cut, weld or clamp. It also rusted quickly compared to current automotive practice.

Stainless steel is much more expensive and lasts the longest, but is extremely hard to work with and will stretch with heat. You will sometimes see stainless exhaust parts need trimming from stretching or rubbing against other parts after having stretched. Many cars come with factory stainless exhaust systems, but the factories can benefit from the economies that high volume and automation can provide.

Aluminized seems to be the most preferred aftermarket exhaust material today...much more economical than stainless and lasts a long time, thought not as long as stainless, but is much more easily worked with.

I have had aluminized on mine for about 5 years now and it still looks good, no rust. They are stained where the rear diff leaks but other than that still look like new. 

Thanks guys - I'm going to go with the Aluminized.....thanks again!!

Brian