The Nissan Path

I've never had the problem, but I have heard of a number of VQ40DE owners that experienced low oil pressure issues caused by a seal/gasket failure at the back of the rear timing cover. User "usafaviator" at NissanHelp.com recently provided a link to a good article on the topic with pics. I'm providing the link to the forum page for those interested; the link is at post # 66:

http://x.nissanhelp.com/forums/pathfind ... les-5.html

I was just reading something on this issue the other day. It seems to be more of an issue with a small number of early VQ40 models? I think the one I was reading about was a 2007 if I can find the article I will post the link. I wonder if high mileage motor oil that has seal conditioners would help the issue (swell the motor seals?) I also wonder if they changed this design with the later VQ40 engines since We have not seen any more current issues with this problem? Or should I say I have not seen any forum posts about the issue from more current years.

Regardless the number of VQ40 motors with this issue seems quite small compared to how many are out there.

It's a small number, but good to know if you run into it. I do know the part # of the rear timing cover has been superceded a couple of times, so hopefully they fixed the problem.

I believe I'm having this problem. At idle (1200rpms) oil light comes on. As soon as I rev to around 1500 (or am driving), oil gauge returns to "normal." Sender was replaced, to no effect. Do I sound correct in my assessment? How much harm is being done every time I drive it? I'm assuming it'd be pricey...right?

I can't tell you how much harm is being done, but low oil pressure is never a good thing. It would be a pricey repair. I know gallery cover gaskets are available for the 3.5L, which have the same problem, but I'm not sure if they are available for the 4.0L, yet. If so, it would be a lot cheaper for the gaskets than it would be for the rear timing cover, obviously. Replacing the timing set on these vehicles will usually run around $1600, give or take and depending on where you take it to, so I would expect the rear cover would add several hundred dollars onto that job, if the timing set is replaced, as well, while apart.

What would be the best way for me to go about finding out if the gallery cover gaskets have been updated or to find a part number for them? Just call the dealer and ask?

I guess you could contact your dealer's parts dept.

You can’t get this gaskets separate unless you order them under Infiniti G for whatever reason. I always replaced the whole rear cover as it’s 2-$300 iirc. Pull the oil sender and put a mechanical gauge on it and check pressure at idle and 2500 rpm after warming up engine. Report back!