Towncivilian

I wouldn't jump straight to SECU. Your door switches could be busted, inspect them all. Don't forget the hood switch too.

What is the model and FCC ID on your remote?

The water control valve is a smaller thermostat at the rear of the engine near the firewall. It opens at 210F. The main thermostat is fully open at 176F.

Thanks for that info! I was wondering what the upper range of "normal" was on the gauge. It starts showing normal at approximately 152F.

I have not seen higher than 195F here in Florida. All original cooling system except for the coolant of course - had a flush done @ Nissan around 70k miles, then a drain & fill around 115k miles with Nissan Green coolant. Everything else stock except for the hose between the radiator cap and the overflow bottle (it was weeping), and the cooling fan blade which had many cracks in it (don't know how to explain that one). See this TSB, it'll help you inspect your radiator cap properly. Replace with an OEM one if necessary.

I use a 1/2" to 3/8" adapter to use the 3/8" drain plug sockets, it works just fine. The adapter even acts as an extension depending on the type. I used the 10mm drain plug socket for the plugs on my mom's '12 G37 rear diff, I'm glad I bought the set!

It's a little blue case in the automotive aisle. I passed it three times before asking somebody where they were - and the employee just stocked them in front of me! Facepalm. Print out a 20% coupon and bring it with you, and maybe print out the product info page to help an employee find it if you can't. Google should yield results with the first link - just search for "harbor freight coupons" and "harbor freight drain plug socket set".

The plugs are actually 13mm drain plugs, so you may want to get the drain plug socket set from Harbor Freight to help avoid rounding off the plugs.

Yes, a leak from the transfer case is still possible.

That fluid looks red colored based on the last picture. Is the power steering fluid level within range? How about the transmission fluid? If your Pathfinder is 4WD, check the transfer case fluid level as well.

https://docs.google.com/file/d/0B5mpmm482r0VcWhqRTdqNG5jTk0/edit?usp=sharing

Pick your year from http://www.nicoclub.com/FSM/Pathfinder/

This is a 1989 D21 manual, which should be close enough: http://www.nicoclub.com/FSM/Hardbody/d21_truck_1989.pdf It's 112MB, so you may want to right click -> save as.

Just try the fluid alone first, if it still chatters on figure-eight turns then add some as required. If you don't end up needing it, return it.

Yes, overfilling by over a quart or so is not good.

Just under 3 quarts.

That's fine.

I've used both Techron and Gumout Regane; since both contain PEA, they both work well as far as I can tell. Techron can usually be found as BOGO free at some auto parts store every month, but if not I usually just get Gumout Regane from WalMart since it can treat more gallons than Techron for the same or cheaper price.

Most "injector cleaners" are more or less useless, and contain mostly kerosene. Fuel system cleaners such as Chevron Techron, Gumout Regane, and Redline SI-1 are much more effective since they contain PEA (polyether amine) which is a proven cleaner that doesn't leave deposits behind such as solvents would. And when a fuel system cleaner is in the gas tank, many shorter city trips (but not so short as to not reach operating temperature) are ideal since the time spent sitting between trips allows the cleaner to soak in and work better.

Even R50s through 2004 only specify GL-4 or ATF for the transfer case. Doesn't GL-4 have more anti-wear additives anyway? I don't remember right now.

The FSM only specifies GL-4, so I would not chance using GL-5 in the transfer case.

Engine coolant temperature sensor?

There is a TSB about ECM reprogramming if rear oxygen sensor codes pop back up after replacement. See here.

Cut open your used oil filters and make sure there wasn't any failure of the filtering media, like a blowout for example. It's rare but that could be a possibility I'd imagine. You'll also see if the filter has caught any big chunks of stuff that way too.

Are you sure they're magnetic? Try to pick them up with a magnet. Which NAPA filter? They have several lines of filters.