Bought 2 weeks ago. 181,000 miles.

Coolant spews out overflow at high RPM. Burped radiator for 30 min, on 3 separate occasions, bubbles never stopped. On a plus note, truck doesn't overheat even with rad level low.

I'm guessing this must be a HG.

How much is this going to set me back? Is it a repair worth doing or is block crack / head warpage likely?

I live in Southern Maine, don't know who's qualified to do this kind of more serious work. I'll start my price shopping at the dealer as a benchmark.

Wow! Doesn't sound good. I'd take it to a good local mechanic like Scotty Kilmer (in Houston unfortunately). coolant test by scotty kilmer - Bing video

Dealer in Maine... who knows. Can you smell combustion in the coolant?

There's a kit you can buy to check the coolant for HC leak.. https://www.amazon.com/Block-Tester-...gateway&sr=8-7

Good luck.

Any white smoke out the tail pipe? Good that it doesn't overheat. Foaming milk shake in oil cap? Before you try all the stop leaks for HG, find a mechanic and see what the HG replacement costs. They say OEM gasket is the best WayTG, but a mechanic will know.

2005 SR5 4runner with 145,000 miles. No HC issues.

Thanks for your response. I probably should make it official and do that coolant test.

I'm not thrilled about going to dealer, but not knowing independent engine overhaulers, I'm nervous it might get done and fail again.

Congratulations not having HG issues yourself though!

My 05 with 200,000 miles is in the same boat. Coolant always flows into res and has a lot of bubbles in the lines, but never overheated. I used a HG test kit from amazon and I got the dreaded Blue to Green liquid change. (even worse is yellow). With the amount of miles, my mechanic mentioned a engine swap is even easier on these trucks and may be better route with my higher mileage. Also, it means I can drive this engine into the ground and not worry about it overheating causing warped heads because I'll just replace the whole thing.

Honestly, I hope to drive it another 50,000 miles on the HG leak and then decide what to do when the time comes. With a higher mileage truck, it makes more sense to swap for me.

I had the same thought early on, drive it into ground then swap motor- but I read somewhere we have to use same year model for engine swap. I don't really want to put a problematic model year engine back in. The rebuilt engines probably have better gaskets, but are much more expensive. Is the year model thing true, anyone know?

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03-05 were the problem motors. Find a used 06-09 V6 1GR-FE and it will swap in. These motors are found in the 4Runners, Tacomas and FJ

If doing an engine swap stick with 07-09. even some of the 06 had build dates from 05 with the crap HG.

Okay. Thanks guys So, is the notion that you can't put a different model year replacement engine a fallacy?

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Any suggestions for where to source an engine?

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I'd like to have a 2007+ installed, but it looks the engine was vvti in 2004, but became dual vvti in 2005. Would this change make it incompatible with my ECU?

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the general consensus here is that there are many minute changes for every way, that its best to replace apple for apple, 04 for 04, 07 for 07, you could do more research on the issue, before deciding to take the plunge

I think you're referring to the 2UZ V8, they were non VVTI up until the end of 2004MY and became "single" VVTI (intake cam only) in 2005 and up through 2011 when that motor was discontinued.

The 1GR V6 has always been a VVTI motor, single cam (intake) 2003-2009 and became a dual VVTI engine in 2010 when the 5th gen came out. This is why the 5th gens have more power. Any 1GR from any 2003-2009 Toyota 4R, Taco, and FJ will work. I'd look for an 08-09 with low miles. 03-05 and some 06 have the HG issues, and I've seen an odd number of timing chain issues with 2007MY for some reason. May be nothing, but I never see problems with 08-09 motors.

I might try the bars HG sealer if I were going to sell it.
Some say it fixed the problem for long time.

Downside is it can gum up things - like radiator.

Yeah, I thought about trying the sealer- but if I end up having the HG replaced, instead of swapping the engine, I don't want to set myself up for failure having that in the radiator.

It's certainly tempting, although it seems hard to believe the sealer will work if the HG only leaks primarily under high compression. Seems like the sealer would just get blown out by the exhaust gas before it ever set up.

Wish I could just find a reman 2004 engine, so I would know the head gaskets are of updated design . I just read recently reading from another poster that he had success installing a 2003 engine in a 2004. For whatever reason, seems like the 2003s are less susceptible than the 2004s.

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Had it looked at by a mechanic. Let them know this engine is known for HG failure, and that I'm having boil overs under heavy acceleration.

They did some tests. They say it passed radiator pressure test, combustion gas coolant test, compression test and leak down test.

They're replacing the rad cap and thermostat. Maybe I'm getting lucky? (So far)


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