Hello everyone, I am new to this forum and a couple of days ago I bought a 2005 Pathfinder SE with 117k Miles. The truck is in good shape beside the hood and I paid $3100 canadian for it which is like $100 US these days.

The previous owner didn't change the timing belt when we was told so the damage eventually ended with piston slap and the truck needing a new motor.

So I have embarked on an engine project over the winter, I don't need the truck until Feb so I have 2 months or so to get this project done. I googled and googled for the last 3-4 days and haven't found any info on rebuilding or replacing one of these motors so either they are very reliable or everyone just pays someone to do it.

Here is my beast.

Here is a huge thread from a guy detailing his VQ40 rebuild. You may already come across this, but like you said, there isn't a lot of info about this topic.

http://www.clubfrontier.org/forums/f11/ ... ads-43308/

Good luck man. Takes lots of pics.

sangheraent wrote:Hello everyone, I am new to this forum and a couple of days ago I bought a 2005 Pathfinder SE with 117k Miles.
The previous owner didn't change the timing belt when we was told so the damage eventually ended with piston slap and the truck needing a new motor.

1) welcome to the forum
2) it's ultra rare to have a catastrophic engine failure with a VQ40
3) there is no timing belt or replacement interval
4) there is a timing chain, which has no replacement interval, though they can make a lot of noise if the tensioner guides wear out
5) IF it has "piston slap", it wouldn't be from the timing chain. Piston slap is a term generally used to describe noise as a result of wear or damage between the pistons and cylinder walls. About the only thing I can remember causing this on a VQ40 is the result of failed catalytic converters.
6) better to diagnose a problem properly than to rely on what someone else said
7)$3,100 Canadian = $2,329.87 USD

The VQ has been in the US for 20 years in one form or another and minus a quirk here and there, it has been a very reliable and flexible engine for Nissan. With no disrespect to the great VG engines, one could make a fair argument that the VQ may be the best V6 Nissan every built. It's seen duty in everything from Maximas to vans and trucks to the power-monster in the GT-R. The first year or two saw the need for a starter that spun faster and an update to the primary chain guide. Some of the 3.5L's had some issues with the oil control rings sticking and not sealing properly against the cylinder walls, resulting in oil burning. Some also had some problems with power valve screws falling out and into the engine, but that was more of an assembly issue than a fault with the engine. Then the 4.0L had some upper chain issues that would cause them to wear through the tensioner faces, but that was more of an issue with the company that made the chains rather than the engine design, itself. Otherwise, it has been pretty rock solid and made Ward's list of best engines for a number of years.
Rebuilding the VQ is not the easiest task, either. I think most would tend to replace with a used or reman engine then take the time out of service and the labor required to rebuild a VQ engine.

There are a few companies that make rebuilt engines that offer the VQ40DE V6 you can purchase complete in a crate ready to install. I don't have any idea what they cost but that's one option. Then again you could call a few of the giant junkyards and buy a used VQ from a wrecked Pathy. If I had a real solid truck I would spend the $ for a nice rebuilt engine. And I would most definitely drop in a new radiator even if the current one checks out ok why take the chance.

By the way considering how many VQ40DE V6 motors are out there in Nissan Pathfinders, Frontiers, XTerras etc and I'm sure many are abused and not taken care of like others are it seems quite rare that I read of a motor failure on any of the forums. It's a testament to the durability of the Nissan VQ.

Yes I apologize piston slap was not the correct term the valves hit the piston tops. The truck around here with that many kms on it is worth around 9-11K so I am hoping to get a rebuilt engine in the truck for around 7-8 giving me 4-5K to get that done.

The previous owner had the dealership replace the timing chain and guides only to be told the engine was no good. 5 minutes with an inspection camera and anyone could have told him that. poor guy. I am going to see if I can get all of the maintenence records from the dealership.

From what I read these trucks are amazing hopefully this one is too!

I thought I would post a progress report. The engine has been replaced the brand new timing chains and guides from the old engine were transferred and installed into the new motor and it runs great. Just have an issue with the a coolant leak from the heater core crossover fitting dealy.

The body work all finished as well not a perfect job because the outter panels were bent outwards but only a trained eye can see the issue. To fix it back to 100% it was going to be almost $3000 which in this case wasn't worth doing. Removed the plastidip from the wheels as well not done yet but started to anyway.


My subwoofer was blown as well making the worst rattling sound I have ever heard. I was going to pull the panel off and unplug the sub and then realized only one of them was blown and decided to try some rtv and that worked great! The speaker system sounds amazing!

FYI, while Nissan doesn't sell the subwoofer speakers separately, you can get them from Bose Corp. Last time I checked, it was around $75 with shipping in the US, or, just a little more than it cost me to send the speaker out and get repaired, which cost about $65 after shipping.

I called them twice no response. This cost me $0 and it works perfectly. I'm actually shocked at how well it works.

Im willing to try doing this a couple more times if this fix fails. Then I am going to rip it all out and put in a shallow mount sub in this location with an amp under the 2nd row seats.