[imagine-02]

I was cruising along at about 45mph when suddenly it felt like I locked up my brakes. I instantly pushed the clutch and stopped the truck. While idling I started hearing a very loud engine knock/tick. Luckily I was close to my shop and was able to limp it there.

Here's a video of the noise.

I'm thinking the noise is a piston hitting a valve. Engine internals HAVE to be messed up since whatever broke locked the engine up momentarily while I was driving.
I've been reading about Nissan engine problems and have an idea of how this could have happened. Please correct me if any of this is wrong. The EGR system on Nissan engines uses the variable valve timing to suck gas back from the exhaust manifold into the combustion chamber. Some Nissan engines, if not all, have the catalytic converters positioned very close to the exhaust manifolds for optimal emissions efficiency. Well when cats get old, they can break apart. Since these engines suck exhaust gas back inside, it's very possible to suck in chunks of the cat, which then of course get smashed by the piston and/or valves.

I'll be tearing into the engine to make sure it's not a minor fix, but at this point I'm pretty much planning on replacing the engine with a used "low" mileage engine. I would rebuild it, but I know first hand how quickly that can nickel and dime you. Rebuilding the VQ40 with high comp pistons, aggressive cams, and custom tuning with E85 would be so awesome though! Someday.
While replacing the engine, I'll also be fabricating a complete exhaust system. When I'm allowed to start posting in the DIY section I'll start a thread about that.

 

[R00]

By your description, its very possible you had backflow and sucked some cat honeycomb in. I live in fear of this every day. It does happen.

 

[Zedbra]

That does not sound good at all. Would the cat honeycomb be strong enough to bend a lifter?

 

[smj999smj]

The lifters are solid on VQ engines, actually "valve tappet buckets," so I doubt they would have got damaged. I suppose a valve could have got vent. Most of the time when these converters break apart and cause damage, it's only very tiny pieces that get sucked back into the combustion chamber which gradually score the cylinder walls over time until they start burning oil. Has the engine been making a "whining" noise prior to this? Upper timing chain issues are fairly common on 05-10 models due to poorly stamped chain links, which cause the chains to cut into the plastic tensioner faces until they start riding across the top of the tensioner plunger. Eventually, if left unfixed, it could cause the timing chain to jump.

 

[imagine-02]

Does anyone know what the difference between 2002-2008 engines are compared to 2013-2015?
I'm finding low mileage newer engines for less $ than older ones. Just wondering if I could put a newer one into my 2005.

 

[mtyler11]

Does anyone know what the difference between 2002-2008 engines are compared to 2013-2015?
I'm finding low mileage newer engines for less $ than older ones. Just wondering if I could put a newer one into my 2005.

I know there were upgrades/line improvements (like the timing chain)... I'd go for the newer engines...

side note... early engines with low mileage??? wouldn't think that's possible nowadays... also, gen 2 (vq40) began in 05... if they're(recycler) giving you quotes for 02-04 then they're confused...

 

[imagine-02]

Here are two examples I was looking at.

05-08 ( 76K MILES for $2,019.98 )
05-08 FRONTIER ENGINE 4.0L (VIN A 4TH DIGIT) VQ40DE | eBay

13-15 ( 22K MILES for $1,699.95 )
ENGINE (22K MILES) 4.0L VIN A 4TH DIGIT VQ40DE FITS 13-15 FRONTIER 141505 | eBay

I want to jump on that low mileage one but am searching for some kind of reassurance that it will for sure work.

 

[imagine-02]

Well I bought that 2013 engine and am currently prepping it to swap in.
The only difference I've found so far is the lower intake manifold. The newer one has butterflies in the runners. I didn't get the ecu with the engine, so I'll be swapping my old style manifold onto the new engine.

Old style lower intake manifold



New style lower intake manifold

 

[imagine-02]

Got the new engine in and running, so swapping a newer style VQ40 into an older D40 chassis is possible with minimal changes.
Besides the lower intake manifold, the only things I had to change were a bracket for the wiring harness (newer style engine has the bracket on the water pipe, older style has the bracket bolted to the engine) and replace the oil pan sensor (newer style uses two sensors, older style uses one. Screw an old style in and leave the 2nd sensor unplugged).

 

[MNCarl]

Wow thats awesome so now you have an almost brand new engine.....22,000 miles on it

 

[Dark Night 18]

So you replaced a 4.0 with a 5.6 v8 or replaced a 3.3 with a 4.0?

 

[Robeartronic]

So you replaced a 4.0 with a 5.6 v8 or replaced a 3.3 with a 4.0?

Looks like he replaced the 4.0 with a newer 4.0

 

[The_Grayt_1]

What year truck did you have and how many miles?

 

[don71]

Were you able to diagnose what happened with the original engine? What caused it die?

 

[penn70]

Who did you buy your engine from? What came with it (exhaust manifold, injectors, etc.) My head gasket went out and I have 225,000 mile on my 2008. I'd rather replace the engine than invest anymore money into it.

 

[imagine-02]

Sorry this is waaaay late, but I'll reply anyway.

My truck is an 05 and it only had around 90K miles when the original engine died. I still haven't dug into the engine to find out what happened with it. Someday.

The new engine was out of a 13 Frontier with 22K miles. I bought it from Garry's Auto Recycling (Crestview, FL) off ebay. Came with wiring harness, intake and exhaust manifolds, all sensors, and the throttle body. No alternator or AC compressor. Was a pretty complete engine for the price compared to others.
I had to reuse my original wire harness, sensors on the oil pan, and lower intake manifold so it would work with my 05 computer.