Which plugs?

[slpdave]

Hello, I am a new member with my first post.

I am not a mechanic or really even greatly mechanically inclined, I do all the maintenance on our 2 vehicles and so far have saved who knows how much money.

Here is some background: We have owned this QX4 for 5 years. it had 78000 miles on it when we bought it, 100,000 miles came and we had to do some major repairs to our old house, plus we had a new baby and couldn't afford to do the 100,000 mile maintenance items.

Well, money is a little better now, and we are taking the QX4 to the beach next month, probably will drive 1500 to 2000 miles in a week. Then it suddenly occurred to me that it hadn't had the maintenance done, well now we are at 149800 miles. This week it is going to a local import shop that I trust and has always done great work for me to have the water pump, timeing belt, tensioners, and pulleys changed. Also I am doing a full brake job. Had the A/C checked by a professional A/C man. The plugs and plug wires and the front and rear differentials are the only things I need help with, I think.

First the plugs.

I need to know what are the best plugs and plug wires for our 1997 QX4. I know that our Ford Explorer is very picky about the plugs used so due to that reason I would like to know what plug to use instead of playing guess the plug.

Also on the differentials (I haven't looked at them yet) do they have a drain plug or do you break the seal to drain the fluid. Then put a new seal in and refill from the fill hole on top. or is it a completely different procedure. Also what fluid should I use in the differentials.

Sorry to ramble on. I am not accustomed to working on anything other than Fords and GM's, so I am a little skittish.

Thanks, David

[slpdave]

OK I have been able to do some research this morning. Looks like the QX4 came with NGK plugs. Is there any advantage to going with a higher end NGK plug over the stock plug on the QX4. We don't race or do anything other than regular day to day driving to work, kids to school, etc. etc.

[kg03]

No I would replace it with the NGK's that came in it. Remember When you bought it the OEM plugs were very likely still in the truck. So think about it if you haven't had a problem thus far then it should have proven itself as a spark plug. I wouldn't worry bout the diffs unless you do alot of towing or off roading. It is a sealed system so no opportunity for dirt and debris to gum up the system the only worry would be heat. I haven't changed mine and I am running about 165,000 miles on my qx and the dope in the diffs looks fine. I have switched to synthitics about fifty thousand miles ago on the engine and transmission oil. I would definitely change the atf and if not synthetic then the oem transmission oil.

[slpdave]

I ordered NGK plugs (OEM) and a set of NGK plug wires (which I suspect were OEM) from http://www.sparkplug.com. I will leave the diffs alone, I do change the diff fluids in my Explorer because I do some off-roading and towing with it. We go easy on the Infiniti.

The transmission fluid and filter is coming after the plugs, plug wires and brakes.

So what fluid is in it from the factory? or will any ATF fluid do?

I would like to know so I can price check local compared to shipped.

Thanks, David

[kg03]

Nissan ATF fluid. Not any aftermarket brands. You can pick it up cheaper online. if not then it will be quite expensive at harper or ted russel.

Some people recommend mechanical fluid exchange however harper does not offer this service. All they do is drain and fill. Ted Russel may offer but I don't know exactly.

[fueler]

NGK plugs Timing belt is a great idea at your mileage. Might as well replace the fan clutch while you're in there. Mine went bad not long after the t-belt and it needs to be removed anyways. This is a preventative maintenance. Also some people mentioned the "woodruff key" behind the crankshaft pulley needs to be replaced but mine looked fine. Also you did not mention thermostat - that is a MUST during timing belt change. Also - i'd replace the hoses (there three of them - upper, lower, and recovery - the recovery one is by the thermostat) Also, some things my mechanic found during the t-belt. My cam shaft seals were leaking at only 120k miles. My valve cover gaskets were leaking.

[slpdave]

NGK plugs Timing belt is a great idea at your mileage. Might as well replace the fan clutch while you're in there. Mine went bad not long after the t-belt and it needs to be removed anyways. This is a preventative maintenance. Also some people mentioned the "woodruff key" behind the crankshaft pulley needs to be replaced but mine looked fine. Also you did not mention thermostat - that is a MUST during timing belt change. Also - i'd replace the hoses (there three of them - upper, lower, and recovery - the recovery one is by the thermostat) Also, some things my mechanic found during the t-belt. My cam shaft seals were leaking at only 120k miles. My valve cover gaskets were leaking.

Fueler you hit the nail on the head, The mechanic found leaky seals on the camshaft and 1 other seal behind the timing belt cover. We have had a very small oil leak for a while now but I could never run down for sure where it was so I guess now I know. Also the hoses were rotten so he replaced them at cost while they were up close and personal with the engine. My mechanic said since I do most accessory work on the engine, just leave the thermostat alone and change it when it fails (I can do that and it will save bundles of cash I'm sure).

There was 1 item that I had not checked yet, but I would have when I change the plug wires. The distributor cap contacts are just about worn down to the nubs, so when I do the plugs this weekend I will do the cap also.

David

[RockSClone]

Hey Dave. I have a '97 Pathfinder so the vehicles are virtually the same. Your needs on parts will vary on what you do with the truck. Offroading, performance? I prefer performance. I use Nology wires and plugs(a little more expensive, but a big difference). I also use Mobile One exclusively in my trans and engine, with either Lucas Oil additive, or Royal Purple to keep everything cooler. Good Luck.

[slpdave]

I changed the wires and plugs 2 weeks ago. Used NGK Plugs and wires. The NGK plugs were the plantinum plugs (I paid about $7 apeice for them). The wires were also supposedly better than the stock wires.

After driving for a couple of weeks, the gas mileage has increased to over 20 miles per gallon which is great in my book. Also the engine idles and runs much smoother. So in a nutshell, $100 and http://www.sparkplugs.com and we are good for the road again.

[SnowSurfLax]

20 mpg? How fast do you normally drive? How much city/hwy? Run the AC much?

[GoodOmens]

20 mpg? How fast do you normally drive? How much city/hwy? Run the AC much?

On the highway with cruise-control set to 65 I was getting 21MPG on a recent trip. This was through the appalachian mountains as well and with new plugs, wires, fuel filter and k&n filter.