Hey guys. We just traded in our 2008 Armada SE which we bought new for a 2005 Pathfinder LE V6 with 4WD and all the goodies. It has 75000 miles on it.
I think we are really going to like this car as my wife never really took to driving the big Armada. This car seems just about the right combination of size and power.
The questions I have include:
With 75K, are there any major parts that are likely to fail at this point?
I will be towing a 18ft boat sometimes and need to know what kind of factory transmission cooling capabilities this car has. I see it has an extra cooling unit on the front of the radiator. Is this a transmission cooler? Couldn't tell at first glance.
Do you all have any other suggestions specific to this car that I should watch out for mechanically? So far so good but we have only had it a week or so.
The only glitch has been one of the tire pressure monitors has not been communicating after driving a while and the light comes on erroneously. The dealer did just put on a fresh set of tires. I figure I may just have to live with this one as it is an intermittent problem.
Thanks again guys and I look forward to hanging out on this forum!
New to the PF. A few maintenance questions?
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dwoodard170
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Can you expand on this? I have what seems like valve chatter usually closer to 2,000rpm when under load. I wasn't sure if it was detonation or valves. It's erratic and I wasn't sure if it was even fuel related. I haven't seen this problem discussed around here and couldn't find anything on search so if you could point me in the right direction.....Storm4.0 wrote:
- variable intake valve rattle @3000 rpm
dwoodward - My wife thinks its the perfect size, too. She "commandeered" it as her daily driver soon after we bought it.
The PF is a good tow vehicle. The cooling system is up to the task, but make sure you look into the radiator cooler bypass. After the bypass, a 2nd external tranny cooler would probably be a good idea. There's plenty of room. Also look into the Airlift 1000 helper springs for the rear. Its a cheap and easy upgrade. There's a thread entitled "towing big" that has a lot of good info.
Skinny - do a search for "intake power valve". I remember this being discussed in the past. The rattle is in the 2000-2200 rpm range if I remember. There is a kit that glues something or other to cure the rattle. I also remember that the rattle doesn't hurt anything. I think mine has this rattle. But with worn BFG's and two loud kids, I have a hard time hearing it.
The PF is a good tow vehicle. The cooling system is up to the task, but make sure you look into the radiator cooler bypass. After the bypass, a 2nd external tranny cooler would probably be a good idea. There's plenty of room. Also look into the Airlift 1000 helper springs for the rear. Its a cheap and easy upgrade. There's a thread entitled "towing big" that has a lot of good info.
Skinny - do a search for "intake power valve". I remember this being discussed in the past. The rattle is in the 2000-2200 rpm range if I remember. There is a kit that glues something or other to cure the rattle. I also remember that the rattle doesn't hurt anything. I think mine has this rattle. But with worn BFG's and two loud kids, I have a hard time hearing it.
More than likeley you're hearing the vairiable intake "power valve", it's a valve that opens up the intake runners to create a shorter path for the air at higher rpm to make more HP. Apparently it happens to some people closer around 2000 rpm but mine only happened at 3000 rpm under load when the motor is cold. There is a TSB on it and all that has to be done is slide the valve out of the front of the intake and put some 3M flexible epoxy around where it contacts the intake chamber. There are several threads about this problem and how to fix it on alot of Pathfinder/ Frontier/ Xterra forums. The VQ40 doesn't have a timing belt, it has a timing chain. The belt tensioner they are referring to is the serpentine belt tensioner on the front of the timing chain cover, that gets out of alignment and squeaks. Fortunately most of the fixes for the problems are cheap to fix if you're a do-it-yourself'er. Especially if you do the tranny cooler by-pass before any coolant gets into the transmission.skinny2 wrote:Can you expand on this? I have what seems like valve chatter usually closer to 2,000rpm when under load. I wasn't sure if it was detonation or valves. It's erratic and I wasn't sure if it was even fuel related. I haven't seen this problem discussed around here and couldn't find anything on search so if you could point me in the right direction.....
Yes that tensioner goes bad as well but the internal timing chain tensioner can go bad as well. You'll get a squeal like your car has a supercharger from what I understand.Storm4.0 wrote:More than likeley you're hearing the vairiable intake "power valve", it's a valve that opens up the intake runners to create a shorter path for the air at higher rpm to make more HP. Apparently it happens to some people closer around 2000 rpm but mine only happened at 3000 rpm under load when the motor is cold. There is a TSB on it and all that has to be done is slide the valve out of the front of the intake and put some 3M flexible epoxy around where it contacts the intake chamber. There are several threads about this problem and how to fix it on alot of Pathfinder/ Frontier/ Xterra forums. The VQ40 doesn't have a timing belt, it has a timing chain. The belt tensioner they are referring to is the serpentine belt tensioner on the front of the timing chain cover, that gets out of alignment and squeaks. Fortunately most of the fixes for the problems are cheap to fix if you're a do-it-yourself'er. Especially if you do the tranny cooler by-pass before any coolant gets into the transmission.skinny2 wrote:Can you expand on this? I have what seems like valve chatter usually closer to 2,000rpm when under load. I wasn't sure if it was detonation or valves. It's erratic and I wasn't sure if it was even fuel related. I haven't seen this problem discussed around here and couldn't find anything on search so if you could point me in the right direction.....
Here's a video of the noise.
http://www.youtube.com/watch?v=J6J444x34bw
DAMMMITTTT!!!!!pawjr74 wrote: Yes that tensioner goes bad as well but the internal timing chain tensioner can go bad as well. You'll get a squeal like your car has a supercharger from what I understand.
I have that sound coming from mine.... but not very loud. It seems to get louder when I turn the A/C on so I just thought it was the compressor. Oh well, atleast it's only $200 in parts.. looks like I have a little project to do.Speaking from experience with a Maxima (VQ30DE), when the timing chain tensioner goes bad, it makes more of a chatter sound than a whine. The plunger in the tensioner gets varnished and then sticks in the housing. Proper tension is not applied to the chain and you get the chatter from the loose chain behind the cover.
The tensioner can be replaced by removing a little cover on the front of the engine for access. Slack the chain, pin the plunger, remove the tensioner assembly. Basically, it's step one for a water pump replacement as well (which by the way should be a much easier task in the longitudinally mounted Pathy vs the Max), but you shouldn't need to worry about that until at the very least 200K+ miles.
The tensioner sticking is a distinctive noise, similar to valve chatter. Usually first occurring in cold weather due to thicker oil and it taking a bit longer for the thicker oil to pressurize the tensioner.
At high mileage (200k miles +) you can get a worn chain guide as well. When my tensioner in the Max started to stick, I just took the plunger out and cleaned it so it moved freely again. Left the worn guide in there, and drove it for another 50K miles before finally replacing the Max with the Pathy at 300K+ miles.
From my experience, main cause for tensioner failure is at high mileage the oil level getting low due to leaks developed over extended time, then plunger getting hot with inadequate lubrication leading to varnishing/sticking.
For a high pitched squeal, particularly when A/C kicks on, I'd check the usual suspect, the belt. Maybe a pulley.
Lastly, again from my VQ30DE experience, you'd be very hard-pressed to find a more reliable engine. Anywhere. These things are a rock. She'll serve you well for a very, very long time if you put in the smallest amount of maintenance. If you are good about oil changes/checking for leaks, tranny reservoir by-pass I guess, she'll last longer then you'll ever need her to. Expect suspension work from bits simply wearing out more often than real engine issues.
-DPF
The tensioner can be replaced by removing a little cover on the front of the engine for access. Slack the chain, pin the plunger, remove the tensioner assembly. Basically, it's step one for a water pump replacement as well (which by the way should be a much easier task in the longitudinally mounted Pathy vs the Max), but you shouldn't need to worry about that until at the very least 200K+ miles.
The tensioner sticking is a distinctive noise, similar to valve chatter. Usually first occurring in cold weather due to thicker oil and it taking a bit longer for the thicker oil to pressurize the tensioner.
At high mileage (200k miles +) you can get a worn chain guide as well. When my tensioner in the Max started to stick, I just took the plunger out and cleaned it so it moved freely again. Left the worn guide in there, and drove it for another 50K miles before finally replacing the Max with the Pathy at 300K+ miles.
From my experience, main cause for tensioner failure is at high mileage the oil level getting low due to leaks developed over extended time, then plunger getting hot with inadequate lubrication leading to varnishing/sticking.
For a high pitched squeal, particularly when A/C kicks on, I'd check the usual suspect, the belt. Maybe a pulley.
Lastly, again from my VQ30DE experience, you'd be very hard-pressed to find a more reliable engine. Anywhere. These things are a rock. She'll serve you well for a very, very long time if you put in the smallest amount of maintenance. If you are good about oil changes/checking for leaks, tranny reservoir by-pass I guess, she'll last longer then you'll ever need her to. Expect suspension work from bits simply wearing out more often than real engine issues.
-DPF
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