Repair advice? Blown head gasket on 4th Gen 4Runner?

cam-shaft

Bluebird days
I am just at 100k, no problems yet. I am concerned though, I would recommend 92 octane fuel especially when loaded up. This will help keep the combustion temps down. Another interesting note is #6 is the first cylinder to pop head gasket. Huh it is the back cylinder and on the side of engine that has necked down exhaust that goes under t-case and more bends (holding exhaust heat in longer). Continuos excess combustion temp, debtination causing this over time(90-100k failure) ? Wish i had exhaust temp probes on each cylinder at manifolds, probably would show some interesting facts:) A lot of head gaskets failures are due to debtination. Just a thought that I am putting out their.

Cam-shaft
 
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cpayne5

New member
Hi everyone,
Having the same issue with my '05 4runner V6. Mechanics want anywhere from 2400-4000 for the repair. I feel like Toyota ought to be accountable for all these repairs. I have 100,300 miles on the car. KBB value about $12-13,000. Just afraid of future problems even after the gasket repair. Have you guys had any updates from Toyota?

Thanks!

I never pursued anything with Toyota. I figured it would be more headache than it was worth. Doing the job myself, my out of pocket expense was only about $750. The vehicle was down for about a month as I did the work at night and on the weekends (and between parts and tool deliveries).

We have put about 20k on ours since the fix. No signs of any issues since.

Good luck with yours.
 

vicrc

New member
I have 2004 4runner V6 and just diagnosed with leaking head gasket in #6 piston. I have 137,000 miles, very disappointed and the vehicle is well maintained. Independent service quote at $3000 and local dealer wants $3700. I called Toyota Corp and they are not doing any after warranty assistant with this issue.

Good luck with yours. I just hate the thought of putting $3000 on a $8000 car value. I really cant sell the car to someone to have to deal with the head gasket... its just not right.
 
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New to the forum - 1st forum.

2004 4Runner 4x4 SR5 V6 - only owner, put all 128,000 miles on it myself - same symptoms as many mentioned here. Front end shake for about 10 seconds after cold start then it smooths out. Check Engine light on and VSC lights came on. Scan showed code for miss fire in cylinder #4. Shop first diagnosed it as bad ignition coil. Put in new ignition coil and swapped all spark plugs. Ran fine for 1 day after I picked it up (they didn't do anything about VSC issue - told me I'd have to take to dealer for yaw calibration) and then had same exact front end shake, smooth out and Check Engine light on a cold start. Brought it back to shop and they said it was blown head gasket, coolant leaking into cylinder #4. Quoted me $2500-$3000. I've lost confidence in this shop since they got diagnosis wrong first time around and initially pressured me into replacing all ignition coils (even though no other cylinders were miss firing).

Going to bring it to Toyota to see what they can do, but in the mean time the vehicle seems to run fine after the initial 10 second shake smooths out after cold start. No signs of overheating. Am I potentially doing more damage by still driving with this condition?

This seems incredible to happen on a vehicle that I've always praised as being so great and reliable - hoping to get a better response from Toyota than others here have.
 

wdstang

New member
This just happened to mine 05 181,000 on it. I guess that's not to bad. It was maintained by my local dealership Atlanta Toyota up to 110 k then I started doing the oil changes on my own. Water pump was leaking at 110k I changed it, (simple job). This has been an excellent vehicle, was the wife's from new to 120k then I got her the 2011 4runner because this one has been so good to us. Luckily the new one has lifetime warranty on engine and trans!! So it sucks that this has happened but I have had this one yota to plenty of friends that have had 3 or more gm products to my one!!:Wow1:
 

smkg

New member
Hi everyone, thank you for all of the great information everyone has posted regarding the head gasket/cylinder #6/driver's side issue. I have an '05 4Runner 2WD with 126K miles and was just informed that my truck has the same problem. It's at a Toyota dealership (my trusted mechanic closed up shop a few months ago and haven't found anyone between then and this problem cropping up) - and my service rep said he's not seen this problem very often (HA! He should talk to you guys). Dealer quoted $1700 for machining the existing gasket if it's not cracked, and $3200 for a total replacement with new parts. Additional $1700 for the other gasket, which is not acting up, if I just want to replace that while I'm at it.

After reading the various posts in this forum, I think it's the right place to ask for some additional advice! I called around to a few independent mechanics (FYI: K&H Imports in the San Fernando Valley is no longer doing hardline repair work - not sure if in general or only on 4Runners), and was quoted between $2000 and $2800 for either machining the existing gasket or a full replacement. Not including both gaskets.

Earlier this year I replaced both catalytic converters, plus some air conditioning parts that had failed, at a cost of $3K and have spent another $1300 in various repairs, such as replacing both the turn signal indicator housing and related in the front bumper. It's been a little surprising and heart breaking to find so many problems cropping up on a Toyota with only 126K miles.

Please help advise: I love my truck and would like to keep it around for at least a year, hopefully two. My husband and I are planning to purchase a new vehicle (hopefully a 4R 4WD) in the next year or so, and will sell/trade this one in. What are your thoughts?

Thank you in advance for your help!
 

surlydiesel

Adventurer
If you're thinking about dumping the truck in a year, I would see what the dealer will give you on a trade "as is" and be done with the truck. If you're going to keep it for a few more years, then fix it. This is why I'm planning on the V8 in my future 4runner. Not that this is common but it's freaking expensive when it does happen.

-jorge
 

keezer37

Explorer
smkg,

I would get a second estimate from another Toyota dealership. The biggest in your area. One with a name and hopefully a reputation to protect. Always good to get a second estimate.
I don't fully understand the pricing here. A good portion of the labor is going to be done regardless of whether one or both gaskets are replaced. That's why generally both are replaced. The possible machining is done to the cylinder head not the gasket. The gasket is always replaced. Machining should not cost more than $200. This is where the surface of the head is ground absolutely flat. These are aluminum heads and my understanding is the tolerance (flatness) of the head is more important than in older vehicles that have cast iron heads. It's my opinion that any good mechanic should have the cylinder head machined regardless. If nothing else, to protect his reputation.
All the parts that will be replaced are the head gasket(s) and the gaskets of everything else that has to come off to get to the head gaskets. This is a labor intensive job, hence the high cost. Once you get all the parts off that need to come off, the other cylinder head is just sitting there all ready to go. There's no reason not to really. That's why I don't understand the pricing. Of a $3200 total job, the other cylinder head should account for about another $100-$200 (1-2 hours) labor.
This pricing makes no sense to me. Get a second estimate and ask if the front suspension/steering needs to be removed to do this job. I mention this because on the Tacoma in order to get to other parts that need to come off (timing chain cover), the suspension/steering needs to be dropped. This is by the service manual. My mechanic was able to save me quite a bit of labor by managing to get the timing chain cover off without all this extra labor. I'm talking about 7-8 hours labor.

Hope I explained myself satisfactorily.
 

teotwaki

Excelsior!
Necromancing an old thread :sombrero:


My 12 year old 4Runner has 236,000 miles and may have this head gasket problem but I want to be as sure as possible before replacing the head gaskets. I'm just getting into the various diagnostics right now and plan on testing the coolant for hydrocarbons, running a cooling system pressure test and last of all a leak-down test on the cylinders. No obvious oil in the cooling system or coolant in the oil pan. Engine generally runs fine around town. It could eventually turn out that only hoses and a water pump need replacing. No significant coolant loss yet or any puddles on the ground.

In relation to the head gasket failure I found a great explanation of the interaction of combustion gases and the overheating symptoms of the cooling system here:

http://www.troubleshooters.com/tpromag/200005/200005.htm

......But did you know that a broken head gasket can CAUSE an overheat? Many mechanics don't know this, but an otherwise symptom-less broken head gasket (no yellow gunk on the oil cap, no steam out the exhaust) can allow combustion gasses from the cylinders to leak into the water jacket. Such leakage has several possible effects, all of which make overheating more likely:

These incredibly hot gasses are retained in the system instead of being blown out the exhaust, thereby increasing heat production.

The gas bubbles reduce heat conduction from block to coolant, and from coolant to radiator. Bubbles can create destructive "hot spots" even in an engine whose overall temperature is within limits.

A gas bubble can settle at the thermostat, insulating it from the engine's heat and preventing the thermostat from opening.

Depending on the volume of gas poured into the coolant, and the geometry and configuration of the cooling system, the gas can create huge pressures which continuously push excessive coolant out to the reservoir, thereby overflowing the reservoir and creating a low coolant condition.

Sometimes the pressure created by the combustion gasses do not force coolant out, but instead build up until the combustion gasses are "burped" out the radiator cap and into the reservoir. Such a situation can create "cyclic overheating", in which the temperature raises and lowers at regular intervals (20 minutes has been often reported to Troubleshooters.Com). Another possible mechanism for cyclic overheating is where the elevated temperature "seals" the hole in the head gasket, which then opens again when the temperature returns to normal.

Occasionally "incidental overheating" is reported to Troubleshooters.Com. This means that after the engine warms up, it overheats, and then continued driving brings it back to normal temperature for the remainder of the drive. I would suspect this is a combustion gas caused overheat which happens only while warming up. Another explanation for "incidental overheating" is the gas bubble that settles on the thermostat, insulating it from the engine's heat and preventing it from opening. When something finally happens to dislodge the bubble (a bump, a burp, whatever), the thermostat opens and all gas is blown out into the radiator, eliminating the cause of the problem (until the next time the car stands cool long enough to develop a gas bubble).

Flat Earth Mechanics

Unfortunately, many mechanics believe that all head gasket flaws exhibit themselves as coolant in the oil (yellow gunk on the oil cap) or coolant in the cylinders (voluminous white steam out the exhaust). Such mechanics are almost certain to misdiagnose a head gasket caused overheat or coolant loss. I believe this accounts for many of the Troubleshooters.Com reader reports of "they replaced my water pump, radiator, thermostat and hoses, and it still happens". Such diagnosis by replacement is very expensive, and still leaves the owner to pay for the head gasket when someone finally properly diagnoses the problem.

I believe that in all but the most totally obvious overheats, the coolant must be checked for combustion gasses. If your mechanic doesn't believe it's necessary to check for combustion gasses, either because he thinks a head gasket problem can't cause an overheat or because he believes broken head gaskets always exhibit yellow gunk on the oil cap and/or white steam out the exhaust, I recommend you find a different mechanic. Even if the test costs you $60.00, it's likely to prevent expenditures for "diagnosis by substitution". Also, it facilitates a much more accurate cost estimate.

Nobody wants to be told they must spend $1000.00 to replace a head gasket after they just bought a radiator.

Did the overheat cause coolant loss, or did the coolant loss cause the overheat?

An overheated engine will always spew water out the reservoir, creating a low-coolant situation. Likewise, a low coolant situation will likely cause an overheat (which of course will result in further coolant loss).

Was low coolant the root cause, or was it just a symptom? Obviously, the problem will remain until the root cause is fixed.

The answer is found using a pressure test, together with head gasket tests. There are four places your coolant can go:

  1. Out an external leak from a hose, water pump, radiator, etc.
  2. Out the reservoir as a result of excess pressure from an overheat or combustion gas leakage
  3. Into the cylinders through a broken head gasket
  4. Into the oil through a broken gasket


#4 can be ruled in or out by observing the oil and oil cap. #3 can be pretty well deduced by observing the exhaust, especially on startup. #2 can be deduced with a block tester or smog sniffer. And #1 can be deduced by a pressure test.

In a pressure test, the mechanic removes the radiator cap (after the engine has cooled, obviously), and replaces it with a cap attached to a pump with a pressure gauge. He pumps it up to a pressure above your system's rated pressure, and observes whether it can hold that pressure for 2 minutes or more. If not, there's a leak. The next step is visual observation to find the location of the leak. If it can't be seen, the next step might be to place an ultra-violet reactive dye in the coolant, pump up the pressure, and look for leaks under an ultraviolet light.

While it's possible for a pressure test to push coolant through a break in the head gasket into cylinders or oil, often such leakage requires a greater pressure than that developed by the pressure test. This is why a successful pressure test does not rule out a broken head gasket.
 

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