3.3L V6 2006 Toyota Highlander Exhaust leak

I have a 3.3L V6 2006 Toyota Highlander with an exhaust leaking at the connection shown by the red arrow in the image below. I’ve never done any exhaust work, but I’m guessing there is a gasket there that probably needs to be replaced? Is this a fairly straightforward job? I’m just not sure what that spring around the bolt is for.

Also, I’ve pasted a link below with the parts view. I think the gasket I need is #6, but can someone confirm if this is correct? Thanks (unfortunately as a new user I can only post 1 image)


I did exhaust work once. The key word is ’ once '. Never again. An independent muffler shop can do this in a matter of minutes and you won’t get covered in dirt and rust .


Yep, I’d be very happy to pay a muffler shop to fix this, you’ll be done quick, for not much $$ I bet.


It’s a pretty straight forward repair’

The only difficulty may be removing the bolts’

Start spraying the bolts with penetrating lubricant to help ease in removal.


The springs allow slight movement and a steady tension on the joint. There is a donut shaped seal, part #6, that fits inside. Penetrating oil is your friend here as are impact tools. It is a pain, might wanna just pay a shop to fix this.


The nuts and bolts do not seem to have much rust. let the penetrating oil sit overnight, use a six-point socket and a breaker bar, and it will come off. Or, get an oscillating saw and cut the bolts. RockAuto has cheap ones. I wouldn’t go to a muffler shop, because they will try to convince you to replace $1000 of parts instead of $2.

Sprayed PB Blaster all over the bolts. Waited 15 minutes. They’re not moving at all. Took the grinder to one of the bolts and only half of the bolt fell off. It appears that there are two square nuts welded to the flange on either side (red arrow) and the bolts thread through these. Cutting those square bolts off with a grinder will be tricky as they are so close to the pipe and the edge of the flange gets in the way. I wish I had a blow torch. Does anyone have any other ideas before I bring it to the muffler shop?

If you’re going to attempt these type of repairs, you should at least have propane torch.

Then the nut can be heated up until it’s cherry red, and then a pair of Vice-Grip pliers,


clamped onto what’s left of the bolt to thread it out of the nut.



Okay the blow torch and vice grips worked well. Before I put the new gasket in and bolt it up I want to make sure I’m installing it correctly. Does the exhaust gasket go in place as shown in the picture, with the concave side of the gasket seated inside the flange labelled “B”?
I was just going to see how the old gasket sat in there, but there’s nothing left of the old gasket. It’s completely gone.

Pretty sure you’re got it right as shown.

Good posts above and good question. Fyi the welded nuts are called captive nuts. Sometimes u see this term in auto magaxines for diyers. Sounds like u got it fixed good for u for sticking w it. Best of luck.

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That does not look like the right gasket to me. The diagram you linked is for 2003. Your title is 2006. While they may share parts, it looked to me like 2 and 6 were messed up. I pulled up same diagram for 2006 and exhaust is different. Similar gaskets but looks more like you need the flatter one for that position. The pipe fits into the other one. Those donuts are usually for sandwiching between where one pipe is flared…

Okay, so installed the new gasket with no issues. I applied some high-temp red RTV gasket silicone to the donut before installing, as this was recommended to me by someone. No leaks at all.
As for TwinTurbo’s comment, I did get the parts at my local Toyota dealer and they used my VIN to order the parts, so I’m sure they are correct. Earlier in this thread I posted a link to the parts view and thought I would be replacing #6 gasket, but the parts technician said it was #2 when I showed him the image of the diagram.
I drove the car around also and re-checked and definitely not leaking anymore.

installed gasket


Well, glad it was the right one. Nice job getting it done. Never used rtv on exhaust before…

That is an active joint, it moves as the engine moves under torque. That is why it has a ball shaped seal ring and is under spring tension. RTV doesn’t belong there.

The flat gasket in the diagram is for the 4 cylinder engine, the flex joint is in a different location.

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I’m not 100% sure, but I thought I read that the orange Permatex rtv could be used on exhaust applications

Congratulations on overcoming the problems and getting this completed. I personally would just watch the joint for a week or two, and if it doesn’t leak it should be fine.

Nice job on the fix, just my 2 cents worth for any future repairs, permatex wasnt needed, wont hurt anything itll eventually burn off, those type gaskets do allow the system to flex and carbon helps seal them as they “wear” in, good job on the repair, really good job on not cranking the bolts all the way in (most try to) they basically just achieve enough tension to seal but allow joint to flex…shops do fix things but usually for high$$…I’m a huge advocate for DIY, keep up the good work, cars aren’t typically overly complex, even modern ecu controlled cars can be diagnosed fairly easily so jump in and try, use this mind set…its already broke, it’s hard to make it more broke, might as well try fixing it lol