You will not see coolant in the oil on 4th gen HG leaks, the coolant is leaking into the cylinder rather than into the oil. If you look at the below, the water jacket is around the cylinder, the HG is making the seal and where it fails the coolant passes into the cylinder.
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Is the UView Combustion Leak Tester an accurate way to test for a potential HG problem?
It seems like it's most often cyl #6 that has this failure. Any reason for that?
My 2004 LTD V6 has 139K miles on it, and has none of the noted symptoms at all. It's all highway miles, no offroad or towing. The truck runs GREAT, which is why I've kept it this long. I am constantly amazed at the pickup it has. But hearing about these kinds of issues concerns me. I wonder if it's getting time to trade her in. But, dang, the new ones are exPENsive.
Yes, like this.
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Mine passed the gas in radiator test. We positively confirmed it based on others experience here, symptoms and a borescope.
04 4Runner v6
120,000
Cylinder 6 leak
Weighing my options now. Dealer quotes around 3k give or take. Vehicle is paid off and like someone else said, it's "mine" and I love it. So I may bite the bullet and have it done. It just blows knowing this is an issue with so many people but yota won't issue a recall.
04 4Runner v6
120,000
Cylinder 6 leak
Weighing my options now. Dealer quotes around 3k give or take. Vehicle is paid off and like someone else said, it's "mine" and I love it. So I may bite the bullet and have it done. It just blows knowing this is an issue with so many people but yota won't issue a recall.
That is interesting, especially the bit about the Nov 2005 shift to a new part number and design. I always had read that '06 trucks built in '06 got the new HG, but it's cool to finally have some part numbers and dates to see that change did take effect. Mine was built in 02/2006 according to the build tag, so I'm hoping I don't run into this issue down the road.Good evening everyone.
I recently purchased a 2006 Toyota 4runner Limited. After the purchase I read about the head gasket issues of the V6 from T4R.org. (prior to the purchase I didn't know they had head gasket issues).
I went back to the toyota dealer and had them test the oil to ensure the there were no exhaust mixed in with it. This passed.
I also performed a compression test on all cylinders when I changed the spark plugs out and all cylinders were at the correct compression.
Anyways, when I was at the dealer, I asked the parts department to provide me head gasket part numbers for a 2005 and a 2006 V6 4Runner. They were different!
2005 4.0 V6:
Back - 11115-31030
Front - 11116-31010
2006 4.0 V6:
Back - 11115-31031
Front - 11116-31011
So they changed the part numbers between 2005 and 2006 build years (in November 2005 to be exact)
When I asked the general manager about the difference, he said that it was probably just a numbering in their system and not necessarily due to a product change. I told him that manufacturers don't just change part numbers out of the blue. they would keep the same part number through-out their product line unless a chance was performed which would dictate a product number revision.
The manager disagreed with me but I'm standing firm that this is proof Toyota knew of the issue in late 2005 and in Nov 2005 they corrected the head gasket issue and released a revised gasket with the new part number to go with them.
Sorry this post got lengthy. I hope it helps fellow 4Runner owners that are wondering about their gaskets.
I had cyl 6 go out on my 04 4x4 4Runner with 170k. I replaced the gasket and resurfaced the heads and I'm at 181k now with no issues. Thanks for putting this thread together!