3.4l rebuild or not???

98yota_guy

New member
My runner is pushing the 250k mile mark. It's still running strong, and have replaced plenum gaskets, valve cover gasket, etc. So no leaks. Its my daily driver, and every other weekend I drive it 400 miles on the interstate. It isn't giving me any problems as of now, but I know its old and its got a few miles on it. There's a slight tick/knock, haven't really looked into it yet. It's very quiet, but I know it will only get worse. I've done lots of mechanic work in my life, and am in college now for a master diesel mechanic. I'd like to know if a rebuild would be worth it when the time comes, and would it prolong the life of my runner, or would I be better off with a new engine. If I could rebuild and get another 250k miles out of er, that'll be what I'll do.

Any help is greatly appreciated. Thanks ya'll.
 
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I'd like to know if a rebuild would be worth it when the time comes

To put it bluntly - you have no idea what will come or what form it will take.

Thrown rod shot out of the hood? Rebuild is probably not going to work but you already know that.

My point is just that its pure speculation at this point. 4RunningDaily sounds pretty happy about his engine swap so if I ever have any trouble with mine again I will probably go that route.
 
where is the write up for this valve adjustment? can it be done while changing valve cover gaskets?

Yes, but there's a bit more to it than that. Short answer, yes you can do it while changing the valve cover gaskets IF you can make the SST work or IF you can pull your cams without tearing down your timing belt.

You'll pull the valve covers, measure the clearance of each valve shim while the cam is rotated away from the shim, and find which ones are out of spec. Then it gets tricky... in theory, there's a tool that will allow you to pluck the shims from underneath the cams without pulling the cam shafts themselves. I couldn't make the bastard work, my shims were baked into place and wouldn't come free, so I had to pull the cams and tap the shims out with a drift. Either way you get the shims out, next you measure the actual thickness of the shim and compare that to how out of spec it was against the cam and that'll tell you what thickness you need to bring it back into spec, which you then order from a parts house. I was working on a 3RZ with a timing chain and was able to remove the cams without completely pulling apart the front end - 5VZ has a belt, and I don't know if you can pull the cams without completely removing the belt (or at least backing off the tensioner, which I think is under the front cover and takes a little bit of getting to)?

I had the motor on a stand. I imagine the entire process is a little more awkward with the motor in the truck.
 
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Having just done this, I say if you genuinely enjoy turning wrenches do it. If no like e has been stated above, look into jdm engines.
 
JDM engine would definitely save a lot of time.

Alot of work just to rebuild it to stock... if thats the case, id do the whole damn thing... bearings... forged pistons... cams... supercharger... fuel injectors... fuel pump... slippery slope heh... thats what they do in the 2nd gen mr2 world.

V8? ...well, a 4th gen 4runner would definitely save a lot of time for that... if thats the case then you gotta do alot to get rid of the soccer mom look, lift... wheels... tires... armor... another slippery slope....

...I think you're screwed... :biggrin1:
 
Me too, but the damn smog laws ruin it.

I thought as long as it was a newer engine than the one you're taking out then it's fine? Or is CA more strict than that?

You can use our PO Box in Colorado to register :) There's no smog or safety checks, just two dudes sitting in a little building.
 
I thought as long as it was a newer engine than the one you're taking out then it's fine? Or is CA more strict than that?

You can use our PO Box in Colorado to register :) There's no smog or safety checks, just two dudes sitting in a little building.

Lucky lucky..

I think it's the same or newer, but then you're getting into the wiring dilemma and it gets really expensive. I think when my time comes I'm going to swap in another 3.4 and supercharge it. Cali laws are ridiculous anyway and I'm sure they'd find something to stop you from driving it on the street. :rolleyes:
 
I woukd just swap out the motor with a used jdm motor. I have done more than few and never had an issue with a jdm motor.
V8 swap is an option though. The Gm LT1 and LS1 have been done and will pass emission as long as all is hooked up and working right. No CEL no codes working obd2 link and visually correct and all is normally fine in most states. Some states require an inspection after a motor swap like this. These swaps are fairly simple in a 2wd not sure what would be needed to do a 4wd. Might need to use a Gm transfer case and custom front driveshaft. Going to search that out of curiosity.
 
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Drive it till it dies then JDM...

My runner is pushing the 250k mile mark. It's still running strong, and have replaced plenum gaskets, valve cover gasket, etc. So no leaks. Its my daily driver, and every other weekend I drive it 400 miles on the interstate. It isn't giving me any problems as of now, but I know its old and its got a few miles on it. There's a slight tick/knock, haven't really looked into it yet. It's very quiet, but I know it will only get worse. I've done lots of mechanic work in my life, and am in college now for a master diesel mechanic. I'd like to know if a rebuild would be worth it when the time comes, and would it prolong the life of my runner, or would I be better off with a new engine. If I could rebuild and get another 250k miles out of er, that'll be what I'll do.

Any help is greatly appreciated. Thanks ya'll.

I did a JDM this Spring. I had a "ticking" start and it slowly got worse. I then diag'd and discovered rod knock. This was confirmed when I found chunks or metal bearing material in the bottom of the pan. I acquired a JDM from out East, pulled my old engine and swapped the parts, as most of the peripheral components weren't compatible. I replaced seals and gaskets, TB/WP etc.
I've been running it all Summer and its running beautifully. My truck was in fantastic condition, so this was the right decision for me. I'd look into the shims as mentioned above and drive it till it dies. Then do the swap. Just my opinion.
 
I'm a huge fan of American Muscle. Worked in a Vette shop for long enough to know that the Japs got the precision thing down. Power-per-liter and over all efficiency go to the Germans and Japs. Please do not rape this Yota with a garbage 350. You will regret it.

Rebuild it and add a supercharger or turbo if you want more power. Otherwise just get a crawl box for off road use. The 22r has no issues spinning rigs up nasty stuff with enough gearing.

The manual swap made mine feel a lot less gutless, just sayin. Added control over gearing and lower ratios. And better fuel economy. Tree huggers are happy and so is my wallet.
 
I'm very happy with my JDM. I'm casting my vote for running her till she's dead; get yourself a JDM, clean it up, new OEM gaskets, and run until it dies again.

If you have the means, get the engine sooner, and plan your swap, rather than going through the stress of being down at an inopportune time.
 
Just out of curiosity what has been the average price for all of you whom have swapped out with a JDM engine?
 

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