Cross posted from the "what did you do today" thread, but if you're like me, you don't read those long threads, and this would be interesting information to me.

Replaced valve cover and spark plug sealing gaskets. I had 1 spark plug hole on each bank filling with oil.

I have always done 10K mile oil changes and didn't find a spec of sludge after 210K miles.




I just found a write up of the same job for the original 1GR-FE in the 4th gen. Interesting comparison of the differences in the head design for the cam bearings, exhaust side VVTi, and the difference in sludge. This engine had only 116K miles. Also, they put in an additional oil passage running through the valve cover spraying oil from the top, which probably is a lot of the difference between my spotless valve cover and the 4th with cooked on oil.

My takeaway is to point out your engine's condition to all those naysayers who don't believe Toyota's 10K OCI. Nice post.

Gives me a warm fuzzy as I'm at 110k miles. Nicely done sir! Man I would love to have one of these on an engine stand and learn how to work on them. Probably WAY beyond my abilities and definitely beyond my current tool complement lol.

wow. as mentioned, very clean with 10k OCI.

Next question is of course going to be... Which oil do you use?

each of the little holes in the pipe appear to line up on the cams. That's an interesting design update. The pictures speak for themselves

Was it easy to spot the damage in the gasket when you removed it?

I just did this on mine about a month ago. I had 1 tube on each side leaking as well. I'm not sure about @Jeremy556 . But, when I pulled the old gaskets they were super hard, so much so that they were not sealing anymore. No visible damage.

Mobil1 0w20

Yep same, the rubber had just hardened up. Mine broke apart upon removal.

Great post!

Awesome review!

Thanks for the pictures! How do the spark plug well gaskets get installed? Any hints or tips for them?

Hey I’m looking for a write on replacing my valve cover gaskets and spark plug tube seals. Can’t find anything for a 5th or 2011 sr5. I’ve heard put the tube seals in the freezer. But that’s it.

This is a great post. Not too many high mileage 5th gens yet, so all the posts on the main page are about roof top tents and bigger tires

I just hit 107k, and posts about higher mileage maintenance are few and far between.

What were your symptoms? Misfire from oil getting past the plug seals?

edit: I'm still learning the finer points of engine design. The seals you replaced aren't between the plug and the combustion chamber, they're the seals from the head/valve cover to the access tube. So I'm guessing you were replacing plugs and found the oil?

I have oil on my plugs. I'm at 170K

I have a 2011. I have all the bolts out of the valve cover. It just doesnt seem to want to budge. Has anyone found a writeup on this job. This job is a pain in the butt. Any help is appreciated.

Your going to have to pry up on the valve cover to get it free. There are just stuck to the old gasket. Its a pretty easy job just take your time. I have quite a bit of wrench time under my belt so it took me about an hour and half.