Exhaust Manifold Replacement

Didn't see a lot of threads detailing exhaust manifold replacement, so....

Truck is a 2010 V6, with the original exhaust system. The exhaust manifold had a small lead in two places. Was quoted C$540 per side for labour only to replace the exhaust manifold, C$1,080 in total. Too much money and I don't like others working on my truck, so I did it myself.

I used OEM parts:
17140-0P140 Left Manifold x1
17150-0P140 Righ Manifold x1
17173-0P010 Manifold Gasket x2
90126-A0019 Exhaust Manifold Stud x12
90178-A0048 Engine Intake Manifold Nut x12

Not all 2nd gens have the same heads - the above parts are for a 2010 V6. If you are in Canada, Toyota manifolds are way less expensive in the US. The other parts are equivalent pricing in the two countries.

Decided to apply high temperature primer/heat paint to the manifolds. For primer used https://www.kbs-coatings.com/xtc-primer and for paint used https://www.kbs-coatings.com/xtc. Never used these product before - carefully followed instructions - time will tell.

Jack up front of truck to get front wheels off ground. Used jackstands and left jack in place.




Used trim tool to remove clips from mud guard.



Removed mud gaurd to allow access to the 6 nuts attaching exhaust manifold to head.



Reach back and unclip the sensor. It is easier to leave the sensor attached to the manifold and remove it from the manifold once the manifold is removed from the truck.



I used an impact gun to seperate the lower end of the manifold from the pipe it was attached to. I wasn't concerned with breaking hardware in this spot. This is the only area I had to cut a nut off, as the stud screwed into the lower end of the manifold got stripped, kept spinning, and I had to cut the nut with a die grinder and cutoff wheel.



Now onto the nuts (attached to studs screwed into the head) holding the manifold to the head. This is where I had prepared myself for the worst. Read about studs snapping, trying to extract broken studs, and all of those other horror stories.

I was very careful removing the nuts holding the manifold on. First, clean off the threads with a wire brush as best you can. Then spray on your favourite liquid wrench...repeat the wire brush/liquid wrench a few times. I started to clean the threads and apply liquid wrench days before attempting to remove the nuts. The nuts broke free fairly easily.....once the nut was loose (quarter to half turn), I would then turn clockwise the same amount, and repeat counter clockwise/clockwise turning of the nut until the resistance was minimal. I only used hand tools, and stayed away from the impact gun. I had no problems taking off the 12 nuts that had been on for 15 years.





I decided it was easier to remove the two bolts holding the bracket to the tranmission housing than to try and cut siezed bolts under the truck, so once the manifold nuts were undone and the two bolts holding the the bracket to the transmission housing, the manifold was lowered and rearwards, between the engine block and frame. Notice gasket orientation on driver side.





State of original manifold after 15 years and ~240K KMs.



The nuts had come out fairly easily so I had the courage to replace the studs. I probably could have reused the old studs, but I had already purchased new studs (incase some of the old studs broke) and I am a bit particular about this truck, so I decided to replace while I was there. Clean the e-TORX end of the stud with a wire brush as best you can, make sure the e-TORX socket is fully seated (ie tap the socket onto the stud until it bottoms out), and then carefully unscrew studs. 11 of the 12 studs came out using the e-TORX socket. 1 of the studs I had to use a bolt remover socket on.



This is the gasket mating surface after cleaning. You don't want to create any gouges in the mating surface, so be gentle. I used a combination of brake cleaner, a brass wire brush, and a Scotch-Brite pad (maroon colour, very fine) to clean up the surface. Took a fair bit of time as there isn't a lot of room to work, but it is import to get these surfaces clean.



Passenger side of block, showing new studs and clean mating suface. I heat painted the threads that didn't screw into the head. I used anti-seize on the studs and just snugged them up - no specific torque setting.



New gasket orientation on passenger side.



New manifold installed with nuts torqued to 16 ft-lbs. I tightened gradually to 16 fl-lbs...starting at 10 then 13 then 16 ft-lbs.



Project took me a full Saturday, taking my time. I replaced the entire exhaust system, from manifolds to the tail pipe. If you can do the manifolds, the rest of the system is easy.

You can cure the high temp paint on the engine according to the instructions, but I had access to an old BBQ (not used for food anymore) so cooked them up that way. 350F for about 30 minutes.

 

What was your total cost in material? Nice work, will probably end up referencing this myself later

 

Great write up! I have a cracked flange on my passenger side and have been debating just replacing the whole manifold as it's also 15 years and 170k miles old. Good to know it shouldn't be too bad if I do go that route.

 

Well done

 

Manifolds were U$759 per side, ordered from Olathe Toyota
Manifold Gasket C$75 for two
Studs and nuts were about C$52 in total

So about U$1,600 + paint. Most money I've put into this truck at once since I have owned it.