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Discussion Starter · #1 ·
I got a QR25DE Frontier which blew hte head gasket....I replaced the gasket and it's still venting into the cooling system. I believe the block is cracked somewhere and am thus looking for another engine.

My problem now is that it seems RWD QR's are about as common as hen's teeth. My options are pretty much limited to $2000~2500 on eBay for a used motor and that's too much cash to drop on site like eBay. VQ's from that generation, though, are about half the cost and available locally. There's actually a VQ Frontier in a local wrech-a-part for about $600 with all the accessories.

So there in lay the question...what else would I have to get in order to swap to the VQ?

And on a tangent...FWD QR25's are literally littered across that wrench-a-part. I'm told the FWD QR25DE won't work because the engine is different (but then how is it the same engine?)...but no one can explain how the engine is different. I've read that it seems to be engine mounts, but if everything else is the same then engine mounts really don't seem like they would be hard to overcome. Is that all that's different about the FWD QR25DE? Engine mounts? Would everything else in my RWD QR25DE Frontier bolt to it over than the engine mounts?
 

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2005 plus is 2d gen. I would have to assume you would need the complete engine, engine harness, and possibly the ecm unless you got uprev to accommodate the larger engine but that is just me assuming. if it's 2005 plus then it has the same frame as the 4.0's. Some of the hoses and such more than likely will be different as well.
 

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Discussion Starter · #6 · (Edited)
sell it and buy a v6
Neat. How much would you maybe appraise a 2005 Frontier at with a bad QR25DE engine? I mean yeah if it's worth as much as a good running VQ Frontier I'd do it in a heartbeat. Wouldn't hesitate.

2005 plus is 2d gen. I would have to assume you would need the complete engine, engine harness, and possibly the ecm unless you got uprev to accommodate the larger engine but that is just me assuming. if it's 2005 plus then it has the same frame as the 4.0's. Some of the hoses and such more than likely will be different as well.
Do you know if the transmission is the same between the QR and the VQ? It's a 2wd setup.
 

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Neat. How much would you maybe appraise a 2005 Frontier at with a bad QR25DE engine? I mean yeah if it's worth as much as a good running VQ Frontier I'd do it in a heartbeat. Wouldn't hesitate.



Do you know if the transmission is the same between the QR and the VQ? It's a 2wd setup.
the information you are asking for, im already telling you that you will not be able to do this swap. on your own at least. whatever you have budgeted for it, double it. easy.

what you want to do is a lot of wasted work and effort since you can easily just go buy a running v6.


i would put some oil seal whatever you need in your engine to get it to run well enough to trade it in and let the dealer **** with it.
 

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Discussion Starter · #8 ·
the information you are asking for, im already telling you that you will not be able to do this swap. on your own at least. whatever you have budgeted for it, double it. easy.

what you want to do is a lot of wasted work and effort since you can easily just go buy a running v6.


i would put some oil seal whatever you need in your engine to get it to run well enough to trade it in and let the dealer **** with it.
First, no amount of snake oil will make it run. Whatever failure it has won't let it compress enough to run at all.

Second, you may be the kind of person to prefer passing your problems off to other people...I am not.

Third, I do not desire to have a Frontier for the sake of having one. I desire to fix this one. Fixing this one requires the engine be replaced. This mean replacing the engine. So far, the cheapest RWD QR25DE I've found that isn't on eBay has been $3400. If I were to buy from eBay, which I'm not spending that much money on eBay, it's $2200. There's a VQ nearby for $600 OTD. I could triple that to cover extras and not be much more than ebay...and I could multiply it by four and be cheaper than the online dealer.

Fourth...cost and effort are my concern, not yours. I do have specific questions asked, though, that I would love to have the answers to if, by chance, you have them.
 

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ohhhh the irony....
well i would answer your Qs, but you dont pass off your problems.

subscribed, post your build in here man. cant wait!
 

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It's not just and engine swap. It's an everything swap. What's different? Besides just the engine, the trans I am sure is different. Front springs for a different weight engine. Brakes, yep the I4 trucks get smaller brakes. What you have is a body shell. trying to build a bastard project vehicle will leave someone a much bigger cluster F- then just selling the truck as is with a known bad engine. And you will be money ahead.

OK, if you really want to try this. Go find a V6 truck that is mechanically sound but is totaled because of some mild body damage. Say a full length side swipe. Make sure everything with the chassis is good. Take that truck and gut the entire cabin. There are going to be differences in wiring, ask anyone who has ever worked on newer Nissan stuff. Now scrap the wrecked body. Take your truck and gut the interior as well. Put the V6 everything onto your body. Now put your body on the V6 chassis. You have just spent 100+ hours of hard work (maybe a lot more if you are learning how to strip and rebuild trucks). At this point you have two different VIN tags. One is for the salvage truck you bought, the other will never pass emissions as the powertrain is completely wrong. If you thought selling a bad running truck so someone was a bit dishonest, wait until someone buys the truck now and it is a mix match of different VINs.

Still comes to selling the truck as is. Be honest with the problems and let it go. Go buy a V6 truck. You will be ahead in time and money.
 

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Discussion Starter · #12 ·
The dealership wanted something along the lines of $8,000 to put in a used motor sourced from LKQ if that tells you anything...but I think the reality was they didn't want to work on it.

I have no desire to have a VQ Frontier. I'm only trying to get this one back on the road without having to spend several thousand dollars to buy an engine unseen from across the country. The VQ is simply an option that is immediately available, thus warrants consideration.
 

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Where have you been searching for engines? have you been on CarPart - Replacement Auto Parts ?

Buying an engine from an Ebay seller is not a huge deal as long as it is a legit Junkyard with a return policy. I would never buy a $$$ item from a private party on Ebay. Also, make sure you are using paypal / CC for payment. Many of them will show "free" shipping or a flat freight charge. I got a differential from a Ebay Seller on the east coast (I'm in MN) paid $150 for freight and when it arrived the housing was cracked making the part unusable. One call to the seller, a few photos texted and he promptly refunded my money and told me to not worry about sending the part back.

With that said, I would also look at the value of the truck both fixed and in it's current state and weigh it against what you may owe on it and what it is worth to you.

And, not knowing details, it is quite possible the swap to a VQ would be difficult as the entire truck may be laid out different and the little details would nickel and dime you to death. Exhaust, driveshaft, transmission, wiring, etc... Unless you could find a complete wrecked 4cyl truck, I would probably not attempt it.
 

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I'm surprised everyone has such low confidence in swapping to a VQ here. How come when anyone talks about a VK56 swap, the response is "it's not bad, all mounts line up, just bolt the engine/trans in, add this adapter harness and everything is happy". I would expect the same for the QR to VQ swap. Motor mounts and transmission mounts are likely the same, you would use the ECU from the QR and may need to get security systems shut off from UpRev, then use the entire engine harness from the QR and make an adapter harness that interacts with the VQ body harness (if this is even needed since you are going from Frontier engine to Frontier chassis, rather than Titan engine to Frontier chassis).

On the other hand, like others have mentioned, there still other differences that are going to add up in time and cost. Such as exhaust, cooling system, etc. It sounds like you don't care about VQ power or anything, so in my opinion I would just try to find a cheaper QR. I would think the cheaper cost of the VQ will be negated when you start adding up the differences and include the time to figure things out. If you were interested in a project with a quest for more power and you have the time and resources to debug the swap, then by all means go for it.
 

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Discussion Starter · #15 ·
I'm surprised everyone has such low confidence in swapping to a VQ here. How come when anyone talks about a VK56 swap, the response is "it's not bad, all mounts line up, just bolt the engine/trans in, add this adapter harness and everything is happy". I would expect the same for the QR to VQ swap. Motor mounts and transmission mounts are likely the same, you would use the ECU from the QR and may need to get security systems shut off from UpRev, then use the entire engine harness from the QR and make an adapter harness that interacts with the VQ body harness (if this is even needed since you are going from Frontier engine to Frontier chassis, rather than Titan engine to Frontier chassis).

On the other hand, like others have mentioned, there still other differences that are going to add up in time and cost. Such as exhaust, cooling system, etc. It sounds like you don't care about VQ power or anything, so in my opinion I would just try to find a cheaper QR. I would think the cheaper cost of the VQ will be negated when you start adding up the differences and include the time to figure things out. If you were interested in a project with a quest for more power and you have the time and resources to debug the swap, then by all means go for it.
I'm not new to swapping engines around, but I'm not a pioneer...and this seems to have had no interest in the past. I can be told definitively that the engine will fit because, structurally, all the trucks are the same. But no one can (or is willing) to tell me definitively if the transmission will mate to the engine. If I have to buy the transmission, too, it's not a big deal, but then does the drive shaft match? If I have to buy the drive shaft will it still match the rear end? And so on. I can essentially buy the entire power/drivetrain from the VQ truck for less than it'd cost to get a QR shipped to me, but it not having been done before hampers my desire to invest in it.
 

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Discussion Starter · #17 ·
Sorry Shizzy...didn't mean to ignore you. The truck is not a primary means of transportation...it's actually been sitting for quite some time before I had time to address it at all. I'm simply trying to get it wrapped up so I can move back onto other projects.

I looked at the website but had some trouble navigating it. All I could find was an "about" button that told me they didn't sell used engines.
 

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Discussion Starter · #18 ·
Oh I see...your first link had no hyphen. I have checked car-part.com and was able to find a couple engines at least in the Dallas area...not an impossible drive for me.
 

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Again I'm assuming, not having done any research, but I would assume that the trans would match up. For the trucks, Nissan only have 3 different transmissions right? A manual, auto for the frontier/xterra/pathfinder, and the auto for the titan/V8 pathfinder/armada?... Like I assumed in my assuming post, other things in the engine bay would have to be swapped over and the wiring would be something else because then you might run into the problem of the engine harness not mating to the qr ecm. If it did, then uprev can take care of the codes and making sure the computer reads everything correctly. Again I'm assuming and now I'm done assuming before I look like a donkey.
 

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Discussion Starter · #20 ·
I'd love it if that were the case, malleusdei321, but if I buy the engine I'm kind of stuck with it and from what I'm seeing it doesn't have much demand out there. I don't want to dive in unless I know for certain.

If anyone knows, though...I'm reading about this engine and its cylinder sleeves. Are those individually replaceable? I have one cylinder venting directly into the cooling system, possibly two, and the head did not seem to have any damage (no visible cracks, was flat). The block was also flat. This tells me that one of those sleeves is cracked. Could that be replaced?
 
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