Well guys I finally made time to work on the exhaust (see my post a couple entries above, post #28). The Walker part no. 53421 piece impressed me. It mated up perfectly with the stock pieces, and the thickness of the flanges seemed to be a bit thicker on the Walker piece as compared to the OEM stuff. The Walker part was not stainless, I didn't think it would be for only $58, but it did have a heavy wall thickness and a nice solid feel to it. It definitely wasn't a cheapie part. I guess the material is what they call an aluminized steel, but I can't say for sure? I can say though for sure that I felt it was a well made part.

Installation: To remove the existing "front pipe" you have to remove four old rusty bolts, two at the front flange of the pipe near the front exhaust manifold and two at the rear. I raised only the front end of the car onto jackstands, then I crawled underneath. Starting with the rear most pipe connection I used an angle grinder with a cut off wheel to cut off the nut side of the two bolts at the rear of the pipe. The original bolts were so rusted and corroded than I couldn't even get the socket to fit over them without a strugle. Just cut through the bolt on the nut side of the bolt, flush with the flange. Then the bolt head will turn and practically fall out of the bolt hole. I used an angle grinder with a cut off wheel but I'm sure you could use a sawzall too, but it's a tight fit in there so tread lightly. Once these two bolts and nuts were cut she was loose in the rear. Now moving on to the front connection of this pipe you'll notice there is very limited access to the nuts since the frame member is only about one inch away, so I thought there was no way to cut these suckers out with ease. I slipped the 14mm socket over the bolt head and was able to turn out the 10 year old bolts with only a 1/2" drive ratchet - no breaker bar and no penetrating oil, so I got lucky. These nuts on this front side connection are welded to the flange piece, so unless you like to create extra work for yourself do not cut any bolts or nuts on the front connection! Once I removed these bolts the original pipe was free and with slight prying I slipped it out of there. Next I took a wire brush and cleaned up the remaining stock flanges so the new gaskets would have a decent surface to seal to. Next I dry fit the Walker piece and it fit like a glove, just the right amount of force to get it seated tightly and all bolt holes, bends, etc. lined up perfectly. I used new bolts and lock washers for the rear flange connection since the originals had been turned into several pieces, and re-used the original bolts for the front flange connection after wire brushing the threads clean. I used red Loctite too, who knows if that's necessary but I figured it couldn't hurt. Once it was bolted in I started the motor and there were no leaks so I was good to go.


All in all, for $72 shipped to my door I got the Walker "front pipe" (with integrated flex connector) and both gaskets from amazon.com. I have to say I'm pleased with the replacement part since it fit perfectly and installation was plenty easy. The hardest part is removing the existing bolts, but since I cut the rear ones off it made the job much easier. If you are going to do this job I recommend to you to simply cut off the rear bolts and then go to your local hardware store and for $4 or $5 get new bolts/washers/nuts.

Sorry guys I don't have pics from my work but once you peek under the car this isn't too hard to firgure out, plus some guys above posted some informative pics.

 

Good job .. glad to hear that you did not have to loosen the whole system to make room.

By the way, I hope you got stainless steel nuts and bolts.

Salim

 

It's almost time to replace my flexpipe. Are the front bolts really welded to the flange of the upstream piece? Sure would prefer to cut those rusty things out...

 

Key here is, make sure you have a good six point socket on those. Heat up those nuts nice and bright, and those bolts will come out. I did mine last year.

 

Just getting around to the flex pipe. The front flange bolts are really rusty and it's hard to believe they'll move - but I haven't tried yet. I've owned my RX (2001 with 107K miles) for only a year and I don't know if the flex pipe or cat were previously replaced. Is this the welded nut setup?

 

I'm thinking it's a nut and bolt with the nut NOT welded to the flange as I looked under my RX to verify. I used stainless steel hardware with some anti seize compound (easier to get off again at a later date). So just hacksaw off the nut side first for starters.

 

Sure enough - heat did the trick.

 

Any one try this flexi pipe: AP EXHAUST Part # 38854 ?

 

I recently had Monro Muffler install some new tires for me. The mechanic informed me that there was a hole in my flex assembly (or maybe he used the word "coupling"?). That explained why my 1995 ES300 (175,000 miles) has been getting louder and louder I guess.

I called my fancy custom maintenance shop, and they said that it would cost a few thousand dollars. The mechanic there also said that the high price had to do with the fact that they only replace the part with a whole OEM assembly. He also said that he has seen time and time again that people who replace just one part and/or use 3rd party parts end up having an O2 sensor error within a month or two and then they have to pay the few thousand dollars to get it done right.

The Monro Muffler guy told me that the whole job is $600 and that he does at least a few each week on Camry and Lexus cars. He says that it is so common that they carry the parts in stock. I am pretty sure that he said that he used "direct-fit" parts, but I'm not sure that they are exactly OEM parts.

Who should I trust?

 

ES or RX? It really does not matter but I asked as you posted this in RX forum.

If it is the flex part, I would say get an non-oem part as long as it is stainless-steel and there is a warranty on it.

If it is the cat-converter and the sensor then I would say .. stick with OEM.

The job can be performed by any competent mechanic ,,, preferably a muffler/exhaust shop.


Salim

 

Thanks for the response. Sorry, I posted this is the wrong place. I landed on this page through a google search on "exhaust-flex-pipe."

Anyway, as you say, it doesn't really matter in regards to this issue.

 

ES has a different set up than RX. The converter and flex pipe are all welded together. I would have no concerns with using a good aftermarket replacement.

This is the Walker part for comparison.

 

Thanks Carguy.

OK, I guess I'll give Monro Muffler a try as an intermediate option between the case of spending thousands of dollars with the custom shop and the case of having some local mechanic screw around with just the flex part from ebay.

 

When you say heat the bolts do you mean with exhaust or torch? What replacement bolts did you guys use?

Thanks

 

fyi http://www.ebay.com/itm/Lexus-RX300-Flex-Pipe-3-0L-1999-2003-/230511981201?pt=Motors_Car_Truck_Parts_Accessories&hash=item35ab95b291&vxp=mtr