'05/'06 Tacoma Head Gasket Failure Poll

Update on my testing, poking, prodding.

Background: February 2005 4.0L, 140k as of today.
1. Air in heater core? -> Yes (for 5 years since replacing water pump! Also, thermostat joint is slightly white/crusty but doesn't look that bad)
2. Issues with heat? -> No
3. Bubbles or foaming in coolant? -> No
4. Combustion gas block tester -> Pass/no leak
5. Losing coolant? -> Not that I can tell or not enough to remember, I know Ive topped it off a few times in 5 years though.
6. Cooling system pressure test -> Pressurized 15psi overnight. Lost 5 psi in 12 hours (temperature change?), I feel this is passing? Also did a 45 minute test (engine was still warmish) and lost 5 psi too...still feel this is passing/related to temperature change or flesh in the rubber hoses.
7. Borescope/spark plug test -> pass? my scope kind of stinks, couldn't see head gasket joint, but the plugs are perfect
8. Blackstone oil test -> TBD (waiting to put more miles before testing)
9. Coolant and oil condition -> minty fresh, no signs of issue at all

To conclude, Maybe I should drive my truck and stop losing sleep lol. I will replace my radiator cap since that is easy enough, and submit a blackstone test since i have the kit. I want to say I will continue driving even if that test shows trace amounts but we'll see when we get there. It is important to note that nothing about my truck's performance alerted me about this issue. It was just the fact that this thread popped up again, and I wanted to have an idea of what to expect from my truck in the coming years.

 

This is why I have a "rainy day" fund. My truck is in mint condition, not a speck of rust. If the head gasket blows, or anything else, it will be repaired.

 

The crust around the joint is probably where you're loosing your coolant.

 

Mine had 240k before i did the gaskets, it stumbled pretty hard when cold on the highway. So I decided to bit the bullet and change them (been good so far 256k now) I had the gurgling for probably 50K that I was aware of never did a block test. I think I drove with them blown for about 100K because my cats threw a code at 90K. P0420 & P0430. If I was smart I would have had the dealer check it when that happened and would have been covered under warrantee.

 

I've got a 2005 4.0L, with 126,000 miles, with a manufacture date of 5/05. I'm the second owner, and it always had good maintenance including a coolant change, most recently at around 100,000 miles.

I got the P0306 cylinder 6 misfire code on the occasional cold start - the engine would run rough or stumble for a few seconds, then clear up and run fine. It happened once, then not again for months. After it happened again, I took it to a local mechanic that I trust. We did a spark plug change, which was fine, then a month later the same code and symptoms happened. During this time, I also monitored the coolant level very carefully, and I probably had to add say 6-8 ounces of coolant. The tip-off was that I had never had to add coolant before.

At the second go round, the mechanic diagnosed the gasket leak with a pressure test and scope, yet it was hard to detect. Only a very small amount of coolant showed up, yet it was clearly pink. The other thing I would mention is that this only happened when the truck was cold, so those of you with the occasional rough start should be on the lookout for this, and it would be easy to miss if the truck was warm. It also doesn't happen on every cold start, even now. So, if you have a second-gen with a 4.0 with a manufacture date before 11/05 (when Toyota changed the gasket design), be on the lookout for these symptoms.

As the truck is in good shape (with a new frame and lower components replaced by Toyota years ago under the recall), I'm going to have the head gaskets replaced by the dealer (local mechanic too busy to do it). Estimated cost is $2900, which is better than replacing the truck at this point.

 

Too bad about the head gasket. I think $2900 to repair them is better than buying a new $29,000 truck.
I've asked around, $2900 for a dealer job is pretty reasonable. I've been quoted $3500 to $6000 from different Toyota dealers.

 

I had an 06,then I joined Tacoma world and heard of the head gasket issue,so I traded my 06 in for a 2015,lot nicer truck and looks better,simply didn't want to take the chance on a $3,000 repair so I put that money towards the 2015,no regrets.

 

2005 4.0 4x4, new frame. Paid off

it’s got 218k miles and everything is original, no head gasket failure. Whenever it does go, it’s worth paying to get it fixed. Rest of the truck is solid

 

2005 4.0 TRD Sport with 304,886 miles and no head gasket failure here in Commiefornia. Rust free and still going...

 

Damn do I hate to be a part of this thread.

2006 - built 09/05, found a leak in cylinder 4 at 140,xxx miles. Thankfully I caught it before it blew. Had the typical symptoms, slow coolant leak, no visible leaking, sloshing sound behind dash, rough starts on cold starts, misfire codes.

Looking at a hefty bill but I’d like to keep my truck for a long time so I hope it’s worth the money. Having the shop do all the timing components as well.

 

Id recommend OEM timing components or you may have trouble down the road. They are worth the extra coin

 

I’ll mention it to them, thanks!

 

Ah man that sucks. How often did you change your coolant though the life of your truck?

 

I bought the truck at 96k miles, no clue about the service before me. I never got it flushed, only just topped off if necessary.

 

While it's all apart, Do the Water Pump. Less headache now then going back in a few months when it's all back together. When mine was done I had everything changed. So I could start off new, More Or Less.

 

Yeah, the coolant turns acidic and weakens the head gaskets. Every 5 years, drain and fill. However, with these particular years it may not be avoidable.

 

Definitely going to be more proactive about that after the new head gasket goes in.