So I did the head gaskets on our 2002 SR5 Sport back in June. I sent the heads to a machine shop to be checked and gone through. I put her all back together and she’s been running like a Swiss watch. Up until 2 weeks ago when the wife came home from working furious that the truck was running like crap again. Well I swapped out the #5 coil as the CEL pointed to that cylinder and the plug was soaked. The truck ran good after swapping the coil but had a rough idle.

A couple days ago I did a coolant pressure test overnight and it lost about 3-5 psi by morning. So yesterday I did a leak down test per Tim’s video and found that the #5 cylinder had massive pressure intrusion into the coolant jacket. Like it pegged my pressure tester gauge.

So now I’m trying to decide my best course of action? I’m really kind of dejected after spending all that money in June to only have to do it all again and spend even more money. I was thinking about buying a JDM motor and just swapping out the motor as a complete unit. The current engine just turned over 300k miles. But after talking with Tim (the toolman) his concerns about using a JDM unit didn’t go unnoticed by me.

As far as I’m concerned I have 2 real options. 1. Buy a used engine and tear it down completely and rebuild it? 2. Purchase a couple of reman heads from CHI in Tx. and just replace the heads. Both options come with concerns obviously but which one comes with the least amount of concern and highest chance of long term success? There are some used engines in the northeast area where I am but knowing the exact mileage is always a concern. There is a 170k motor for $500 about 2.5 hours ride from me. Another one for $1000 that is 45 min. from me that also claims 170k miles. There are others as well but I am really worried about the probability of the heads being cracked on any used motor. So that leaves option #2 buying reman heads and going that route. Hoping you great folks can help me decide what to do here and thank you in advance.

So its only have the 5th cylinder with an issue? That's only 1 side. Why not just do 1 replacement. Why would you touch the other side? Just replace the one head and be done. A Used engine could be Russian Roulette as well. If you are sure the its only the one cylinder. I would just replace that head and use OEM gasket. I would verify that old head it cracked too.. as its possible its fine when checked and a cracked developed in 6 months. Major bummer though and very upsetting.

That is also an option I did not consider? But if it is just a premature head gasket failure than how long before the other side also goes tits up? I did not use OEM gaskets but they were MLS gaskets for a 2002 4Runner. I spoke to the guy at Cylinder Heads International this morning and he said the only way these things crack is by being overheated. This truck has never been overheated since 2011 when we bought it as the second owners. The new heads are $1,000 and he said he has 2 sets currently available but they go very fast and he has been having trouble getting rebuildable cores? I appreciate the opinion very much thank you.

I would suggest since you did all the work and are able to do the work to tear back into it. Don't start zipping bolts out but instead check torque on each bolt before loosening it to see if it's possibly an improper torqued head bolt. You stated you didn't use an oem gasket so that would be my next suggestion. It is possible the head cracked after being checked but not likely. I would look at that head gasket very carefully after checking torque on head bolts before tearing down and removing the head. After this, is when I would start thinking about the next course of action. Not before the motor is torn down. It is good to have options but if it's just a simple blown head gasket that was made inferior to oem coupled with improper torqued bolts then it's a simple fix. Question. Did you install new head bolts or reuse the old ones?

I would definitely pull the one head and determine if it's a cracked head, block or gasket before making any decisions. No sense in buying another motor if it's only a cracked head or gasket. What a major bummer to go through this again so soon.

def a bummer, I would suspect the non oem gasket

I assure you the head bolts were properly torqued and they were all brand new head bolts. I was a tech at several dealerships previously at Mercedes/Porsche, Ford, and at a marina for a short 1.5 years so I have the experience to do it right. I will however check the head bolts before I put it back together and pull it out of the garage. I have another 2002 I picked up that needs brakes all around and I don't have the room in the garage for both vehicles.

I did find a low mileage motor for $500 and according to the seller it is a legit 120k motor out of a 97 Runner. The only downfall is that the engine is a 6 hour drive away? What would you do?

He is correct you bake a aluminum head on a cast block it cracks or warps when overheated. Use OEM head gaskets only. Toyota had many revisions on head gaskets. Its sadly possible the gasket caused your failure. So the head could be just fine and your head gasket failed. Did you torque the head in the sequence of the Factory service manual? I mostly mostly bring up head torque in many steps too. Your heads maybe fine.


Pull the head off and investigate to see what occurred. When torn apart just change the head gasket in the other side if you are concerned.

As its very possible that is all that is wrong. The bummer is that's a project to get it down to that point. Requiring a pile of gasket replacements.

Again as I stated previously I was a dealership tech for quite a few years so I do have the experience doing cylinder head jobs. The bolts were all torqued to the factory manual spec's (which I bought right after purchasing the vehicle). Torqued to spec and then the 2 90 degree turns spec in sequence. If it was a premature head gasket failure then I am betting it was due to crappy aftermarket Fel-Pro parts. I’ve read recently that the Fel-Pro parts have gone down the drain quality wise which is disappointing because they use to be the de facto standard. I’m looking at $1600 all in with 2 new reman heads from CHI and about $600 with no cylinder heads and just all OEM replacement parts. I have to do the brakes on my other newly purchased 2002 SR5 4Runner so the wife has something other than my F-250 which is ridiculously gas hungry. Once that is done I can rip into the Sport and also replace everything on the new acquisition a little at a time because it needs A LOT of love.

Ok.. So you were a dealership tech and you didn't know to use only OEM head gaskets.. I am just a hobby mechanic and I know better then that only because of 30 years of working on Toyotas) . ;-) All aftermarket parts qaulity are going to complete crap. Even oem quailty I think is dropping some.

I know they can be costly. However, now 6 months later you are in the same issue. A head gasket or head issue. Being you took it to a machine shop and they inspected redoing the heads. I would be really surprized if the head cracked but possible.

You probably got burnt on the feel pro gasket. This is why I try to stick with OEM gaskets if possible. I get it, but I learned this 25 years ago, its not worth it unless you want to do the jobs over and over again.

Would the dealership use a feel pro head gasket on a rebuilt head or would they use a OEM gasket? I really don't know the answer to this question. I would hope they used the OEM Gaskets. Granted, I am seeing a lot of aftermarket parts drop off at the dealership now when I buy my Toyota parts at the local dealership.

I am not trying to second guess your abilities nor give you a hard time. I am just giving opinions on what I would do and you asked what direction to go..:-)

I do have a 5VZ-FE complete engine setting here but it has a bad bad head gasket so its most likely baked from a PO mud bogging it. So I wouldn't trust those Heads. Engine ran but was really noisey hence why I replaced it with a spare engine I had with 160K on it.

You can also check with Josh Young how runs an used 3rd gen junk yard for parts. He is in the Pacific NorthWest and you can find him on Face Book messenger. He most likely have used heads that are good. Or maybe even be able to ship you an engine reasonably priced you can even hear running before he pulls it.

I hope this helps you. I cant tell you how many times I did this prior to 25 years ago... Some parts you can get away with Aftermarket. Some parts we cant.

I completely agree about toyota factory parts.
I have only experience with Honda parts.
A imitation counterfit rear brake pad set I got online lasted 15,000 miles and was worn down to 1 mm on inside pad. Package looked like Honda untill I compared it to real Honda packaging for same part.
Same Pilot, I tried a top quality Idle Air Valve at about 200,000 miles. I did not want to clean the black gunk on the original that was stuck.
I do not remember brand, but failed in one day.
Disassembled throtle body second time to re-install original IAV I spent 3 hours cleaning.
Same vehicle my aftermarket water pump failed at 20,000 miles use. Turns out I installed a second rate part. Replaced with OEM.
I prefer to spend more on parts and do job one time.

I don't doubt you followed procedure but FelPro HGs are definitely a red flag in this job. If you still have the packaging, could you tell us where the parts were made? Japan would indicate that it is potentially an Ishino gasket - not bad parts and I have one in my 1FZ. I probably wouldn't be as suspicious of the gasket if so, but being FelPro I'm expecting Made in USA or China which you'd might as well call junk in a 5VZ application.

That said OEM is still best and they are made by Nippon Gasket and only attainable in a Toyota package. You best deal is to get an OEM Valve Grind kit that includes all the necessary gaskets for a top end rebuild. Wouldn't be shocked if the other side goes after a couple years. That being said, did you check if the block is within spec? Easy to give it the benefit of the doubt since it's cast iron but if it's warped you're better off with a used 5VZ. I can vouch for JDM Engine Zone in Belleville NJ but as with any used engine I recommend you inspect and get compression numbers prior to handing over cash.

Thanks for confirming what I thought was the possible cause of the premature failure. I did not check the block but will definitely check it this time around. I will be doing both sides again. No way I am going to do just one side knowing that the parts I used were inferior. If I am going to rip it apart again then I am doing both heads. To check the block I assume I put a straight edge across the face and use feeler gauges under the straight edge at several points on the block deck? I have never actually checked the cast iron blocks on the many other head jobs I've done over the years unless I knew that the engine had been overheated in which case the block got sent out to be machined flat. So that is why I didn't do it this time around.

I am curious if the head deck is level. So please keep us updated. :-) Definitely something to always check. Also best to follow the FSM on jobs like this as well. I feel for you. Been there done this a long time ago. Just a live a learn moment that you wont forget. :-)