Exhaust replacement on 2007 XC70 Topic is solved

[XC70Rider]

Also throwing on a new Bosch 16682 downstream O2 sensor. I already replaced the upstream O2 sensor last December so I'll re-install it.

I bet the hardest task installing this new exhaust will be tracing the wire for the upstream O2 sensor.

[XC70Rider]

Replacing the entire exhaust minus the manifold. I cleaned up the new catback by wet sanding with 120 grit and Dawn. Before I paint the exhaust I'll clean it with denatured alcohol. I let it dry in the sun for a few days before mounting it. I'll turn the engine on & off several times with various time intervals over an hour for the curing process. The curing process gets smokey so needs to be done outside.

After I drop the OEM exhaust I'll cut off the CAT and keep the downpipe.

Only cutting the rotted flange off the CAT. If needed in the future I'll re-mount the OEM Cat then weld on a flange adapter.

https://shop.advanceautoparts.com/p/wal ... er+Adapter

[XC70Rider]

Don't waste your time with these downpipes. No bung for the upstream O2 sensor. I gave them my VIN and also details of it being 2.5T & AWD but they still sent the wrong exhaust. Appears it's not easy to match the downpipe for the 2.5T with AWD.

For a direct fit CAT I ordered A1Exhaust for $184

https://www.ebay.com/itm/Fits-2003-To-2 ... 2776121869

The CAT is SS and the pipes are 14 gauge aluminized steel.

The CAT made by Greenexhaust costs $175 and appears identical to A1 exhaust

https://www.ebay.com/itm/Fits-2003-To-2 ... 3337580161

They both are made in Ontarioa, SS CAT, and 14 gauge aluminized steel pipe. I decided to get the A1exhaust because they offer a 5 year warranty and are a more active seller on ebay.

Not getting the Schutlz SS CAT I listed in the first post becuase they won't communicate.

After I drop the OEM exhaust I'll cut off the CAT and keep the downpipe. The flex section and manifold mounting flange are in good shape. If needed for future usage I'll weld on a universal CAT.

[XC70Rider]

When installing new catback onto an OEM CAT that has a rotted flange what have you done? Do you cut off the flange on the new center muffler to slide on straight exhaust pipe or do you use and adapter flange on the OEM CAT similar to this?

https://shop.advanceautoparts.com/p/wal ... er+Adapter

[matthew1]

Don't waste your time with these downpipes. No bung for the upstream O2 sensor. I gave them my VIN and also details of it being 2.5T & AWD but they still sent the wrong exhaust. Appears it's not easy to match the downpipe for the 2.5T with AWD.

For a direct fit CAT I ordered A1Exhaust for $184

https://www.ebay.com/itm/Fits-2003-To-2 ... 2776121869

The CAT is SS and the pipes are 14 gauge aluminized steel.

The CAT made by Greenexhaust costs $175 and appears identical to A1 exhaust

https://www.ebay.com/itm/Fits-2003-To-2 ... 3337580161

They both are made in Ontarioa, SS CAT, and 14 gauge aluminized steel pipe. I decided to get the A1exhaust because they offer a 5 year warranty and are a more active seller on ebay.

Not getting the Schutlz SS CAT I listed in the first post becuase they won't communicate.

After I drop the OEM exhaust I'll cut off the CAT and keep the downpipe. The flex section and manifold mounting flange are in good shape. If needed for future usage I'll weld on a universal CAT.

Thanks for the feedback, Rider. You may save someone lots of wasted time.

[oragex]

My flange was rotten only on the cat side, on the front muffler side was still flat and nice. I'd guess, it needs to be cut and weld a new flange in place. Not that easy to fit properly - it has to sit really flat with the cat flange

[vtl]

I did the whole exhaust in my XC70 recently: manifold gaskets, new turbo, Snabb downpipe, Jetex catback. Didn't like the Jetex loud sound and the fact the tip protrudes too far towards the ground. The car crawls in mud and boulders semi-regularly, it is assured I will dent/bent the tip on my very first trip. Also the flange was leaking condensed water badly, so I decided to replace catback with a new original Volvo. It turned out the leak was because of the downpipe, not catback, had to use some muffler and tailpipe cement to fix that.

The downpipe is much larger than the stock, I had to bend a heat shield, plus it protrudes below the belly a bit. Thinking about crafting some protective plate. Flat belly is super-important to my needs.

If anyone wants my deeply discounted Jetex catback (made of SS302), let me know

[XC70Rider]

I did the whole exhaust in my XC70 recently: manifold gaskets, new turbo, Snabb downpipe, Jetex catback. Didn't like the Jetex loud sound and the fact the tip protrudes too far towards the ground. The car crawls in mud and boulders semi-regularly, it is assured I will dent/bent the tip on my very first trip. Also the flange was leaking condensed water badly, so I decided to replace catback with a new original Volvo. It turned out the leak was because of the downpipe, not catback, had to use some muffler and tailpipe cement to fix that.

The downpipe is much larger than the stock, I had to bend a heat shield, plus it protrudes below the belly a bit. Thinking about crafting some protective plate. Flat belly is super-important to my needs.

If anyone wants my deeply discounted Jetex catback (made of SS302), let me know

I given thoughts of purchasing the Snabb 3" High Flow Cat Downpipe. Is it a direct fit for the 2.5T? Did you have to plug one of the 2 upstream bungs? Is the downstream O2 sensor at an angle so it doesn't contact the driveshaft? Being made at the factory per order it will take 4 to 6 weeks for delivery.

I got the painted BOSAL catback hanging in garage for now. Will mount it after I decide to refurbish the OEM CAT or buy the Snabb 3" downpipe. I inspected the flange after the CAT yesterday and feel I can refurbish it. If I do refurbish it then I'll drop the OEM CAT and install with a new gasket and mounting nuts.

[XC70Rider]

My flange was rotten only on the cat side, on the front muffler side was still flat and nice. I'd guess, it needs to be cut and weld a new flange in place. Not that easy to fit properly - it has to sit really flat with the cat flange

If the flange does need to be cut I may try this SS band clamp

https://www.amazon.com/gp/product/B078T ... 64S3&psc=1

That will be the last section of the exhaust I tighten while it's slightly raised with a jack.

[vtl]

I given thoughts of purchasing the Snabb 3" High Flow Cat Downpipe. Is it a direct fit for the 2.5T? Did you have to plug one of the 2 upstream bungs? Is the downstream O2 sensor at an angle so it doesn't contact the driveshaft? I sent all those questions to SNAAB but haven't heard back. Being made at the factory per order it will take 4 to 6 weeks for delivery.

Direct fit. Both bungs came with a very sturdy bolts, I removed one for the H2SO. Downstream H2SO is at the correct angle and does not touch anything. I've got an extension cable, too, but it was not needed.

I got the painted BOSAL catback hanging in garage for now. Will mount it after I decide to refurbish the OEM CAT or buy the Snabb 3" downpipe. I inspected the flange after the CAT yesterday and feel I can refurbish it. If I do refurbish it then I'll drop the OEM CAT and install with a new gasket and mounting nuts.

I did that (Snabb DP, old rusty CB) while waiting for a new CB. Cut the slots on the flange edges with Dremel, blow torch it, hit with a hammer - studs will slide out.