I ordered mine from Rock Auto and its been good ever since.

 

From Canada you are getting mid steel foiled with aluminum. You will have the same problem after 5 years.

 

In my case, 9 years.

My Canadian 2002 LS430's original Y-pipe lasted until 2014 (12 years) and 129,000 kms. My first aftermarket pipe lasted from 2014 until 2023 (9 years, 63,000 kms).

My second aftermarket Y-pipe is a DAVICO MFG model 18390 from RockAuto, ordered in October 2023, and the manufacturing quality from DAVICO is _GARBAGE_. RockAuto first sent me a new banged up pipe, no box or anything, UPS just had the raw pipe banging around all the way from the US to Canada. It arrived with a gaping hole where a weld should be, and rattling crumbs of something inside the cat and pipes. It also looks like all of the welding was done by a high schooler.

RockAuto sent me a return label for the defective weld, and when that label was scanned by FedEx, RockAuto automatically shipped me another DAVICO 18390. This one arrived raw (no box) as the first one, with same poor quality welding as the first one, but at least no big gaps in the welds. HOWEVER, upon attempted installation by a trusted local exhaust shop, it was very obvious that the right hand side of the Y-pipe was bent incorrectly from DAVICO's factory. The left side bolted up square, flat, and level, but the right side was off by 3/4". There is no way to bend the pipe close the gap, because it will either be misaligned with the center exhaust at the back, or the flanges would be very mis-aligned and the torque required to seal the gap would cause a catastrophic failure in the near future. The only solution was to cut out a piece of the right-side of the Y and fabricate a correctly-angled intermediary pipe that corrects the misaligned right flange.

DO NOT BUY THE DAVICO 18390 Y-pipe!!!

Instead, I would try the Magnaflow 24169 - I believe all Magnaflow products are 409 stainless made in USA with lifetime rust-through warranty. I ordered one on Amazon 5 months ago, still hasn't shipped yet..

 

i bought the Davico pipe as well and I did have to cut and re-weld a section of it to make it fit. Thankfully I have a Mig welder, but one should not have to do this. Mine has been fine and not leaking since I installed it in 2019.