hey guys. Love this forum. I have a 2006 4Runner v6 4.0 with 202k on it. i dumped about 2k into this car on top of what i bought it for and i love it so far. I bought bilstien 5100. OME springs. Took care of all the maintenance. Got 5th gen trail rims on. Falken Wildpeaks AT3 285-70-R17.

I love this car, wife loves it, 2 of our dogs love it. And i really dont want to get rid of it.

Anyway, history of this car. 1st owner blew the head gasket at 140k, put some "stop leak" in it and drove it for another 10k. Then he changed the head gasket. At 170k the head gasket blew again so he sold it and new owner put a new engine in and drove it for 10k before the head gasket blew again. Changed it, 10k later, Blew head gasket again. i bought it at 190k, had a mechanic put in new head gaskets, resurface the heads, new water pump. i drove it for 10k.......blew a head gasket.

I really dont want to get rid of this 4runner. I love it. My mechanic is going to replace the head gasket for free this time but im afraid it will blow again.


Im thinking to swap in a 5th gen 4.0 next time. i can get one for about $2000 with 96k. Just curious if it will be a an easy swap. I can swap over all the accessories and the intake manifold and the injectors. wondering if there is something that needs to be modified.

Just guessing even though they are fundamentally the same, but I'm going to say no as there are going to be issues with sensors and hardware to cause a conflict. I know looking at the engine of my MY07 vs my MY19 that there are a lot of differences from an electronics and plumbing standpoint.

Bigger question is why the constant HG blow every ~10K miles? Also, is the replaced engine a pre-'06 motor? Just guessing as that may have something to do with it as early generation engines were prone. I think best best would be to find a late model 4th gen motor to swap as a best bet.

The 2010 has dual vvti, ECU is going to be different and there will be more connectors on the motor. 5th gens also use air injection and 4th's don't. The motor will physically bolt in, but it won't run without some computer work. Not worth the effort IMO, I'd find a low mileage 2008-2009 1GR

If head gasket is keep on popping I say it's warped bottom end. Have your mechanic inspect it with a straight edge, filler gauges without head gasket in area where gasket is blowing.

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That would make sense actually. Man, I really love this 4Runner, just sucking me dry lol. Getting expensive.

I will look to find another engine 2006-2009. The problem is that most of them have higher mileage already. Which should still be fine I guess

I have no idea what engine was swapped into this car when the 1st one blew

I blew my HG around 180k miles. I found a salvage 1GR from an '08 Tacoma w/ 93k and have since put about 95k on the salvage motor with no issues, HG or otherwise. I considered just replacing the HG but I knew it had overheated twice and my mechanic talked me into the salvage route.

Just my .02 but I wouldn't worry about an 06+ higher mileage 1GR. Maybe replace the water pump while its easily accessible as a precaution.