ServerTech

Found the ONLY aftermarket exhaust made for the AWD version of the GS350. No the RWD exhaust is NOT the same. Took some pictures to share with the forum. Rockauto sells them for $160 per side. The drivers side one has the special dog-leg bend to fit around the front driveshaft, and the flange is at an acute angle compared to the RWD version.
Pictures show how the rust starts as a pin hole under the clamp, and over time gets worse, turns into cracks around the pipe. The stock exhaust shields have a fiberglass mat under them which catches the winter road salt used here in the rust belt. Lexus uses a very thin pipe for the exhaust, the new ones are TWICE as thick! When I tried to weld to the old pipe it was paper thin in spots!

ServerTech

The old front flange bolts were rusted solid. Started by using an air powered cut off wheel to cut the rusted bolts off. Found a big chunk of rust attached to one of the old gaskets. Then lay out the new pipes, measure three times, cut once. Old pipes were leaking bad in 3 places. new pipes are very heavy, old ones felt light as a feather. This is NOT a performance exhaust, its a heavy duty replacement for the rust belt states!

ServerTech

Reassembly was easy, I used stainless steel band clamps from Rockauto to attach the new pipes to the old exhaust. New bolts from Autozone and new front flange gaskets from Lexus. The special O2 sensor tool is required. My car is quiet again after sounding like a hoppty car for about a year! The gas mileage is up a smidgen, didn't expect that. I guess the old cats were clogged, odd since I only have 62k miles on the car. When completed I saved over $1,200.00 from what the Lexus part costs, the 2007 AWD mid-pipe costs more than newer years.

Gs3500

Good job! I wonder why the 2007 versions are more expensive than newer years. Do you know What's the difference?

speedkar9

Good work, nice to see pics, though I hope I don't have to touch exhausts anytime soon.
Rust in my eye isn't something I look forward to. Did you have a hoist or did this in the garage on jack stands?

ServerTech

Just some old school, shade tree mechanic jack stands. It wasn't so bad, I've worked on old muscle cars for years and have dealt with a lot more rust than this!

MelYW

Servertech. That's a great write up. Yes I too found these at rock auto and it's great to see your install. I have a 2008 AWD.

Now some questions.

The area where the O2 sensors are...is that portion of pipe replaced as well? It looks like the new pipe includes the cats plus a few inches then stops. It doesn't look like it reaches the O2 sensor area. The area below the sensors where the clamps are have rusted through on mine but I think it might be ok when I attach the new pipes?

How many of those gaskets do I need? Rock auto has less expensive versions. Did you consider those?

list of what I need for this job in terms of parts...

left exhaust pipe
right exhaust pipe
gaskets #tbd
oxygen sensor tool only if I need it.

The OEM parts are outrageous so this is a huge cost saver. Thanks again!

MelYW

I forgot the stainless clamps that you mentioned as well as bolts (size and qty on both?)

ServerTech

Clamps I used were Walker # 33231 stainless steel 2 1/4" $8 each
Bolts were in a metric bolt assortment kit from Autozone.
You need 2 round front gaskets, I guess the RockAuto ones will work OK.
You need a special O2 sensor tool, they wont come off without it.
New cat pipes have the O2 sensor bungs welded on, just swap over the old sensors, be careful twisting the wires.
The car is nice and quiet now, so glad I didn't have to spend 2 grand!
Be sure to use the RockAuto discount code! I just Google it and find a fresh one, usually on Dodge Durango forum:
5% Discount Code: CB570F4DB581CE
Expires: March 19, 2017


Good luck
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MelYW

are the new pipes stainless? You think they will last a good long time given the snow and salt up where we live?

ServerTech

They are aluminized steel, twice the thickness of the original Lexus mild steel pipes.
Nobody makes stainless steel for this. And certainly not for $160 a side.
How many miles on your car? These pipes will outlast the transmission, that's for sure LOL
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MelYW

I have 63,000 miles on the car. I plan to drive it until it drops.

Am able to find full system for $1,600. Is stainless steel and goes all the way back to but not including mufflers.

I am now wondering if this is best way to go. I know it's not apples to apples as the davico stop after the cats.

So it's $365 front only and heavier steel vs $1,600 for complete system and stainless.

ServerTech

Same exact miles as my car, I bought it new in December 2006. Exhaust sounds nice! you have a link to that exhaust?

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MelYW

Servertech...here you go. Check it out and let me know your thoughts.

http://parts.autonationtoyotasouthau...xus/1741031831

ServerTech

That's the stock Mid-Pipe for AWD, same as the rusted one on your car now. Just add the 3 gaskets (2 front, 1 rear) and will need an Oxygen sensor tool. And the bolts front and rear. Good as new again!

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