4.6 Motor Question

The 10W40 today is excellent if you don't try to run it too long. 3500 mile changes are no problem. 7000 mile intervals you are begging for trouble (but then, I'd not go 7000 on 5W30 either - same viscosity spread, means same amount of VI improvers, and the same propensity to "shear".

Or fuel dilution (on a pre OBD2 engine - OBD2 will throw a code if an injector leaks- unless the engine isn't running) or oil viscosity breakdown (which has happened to me) or "foaming" which has happened on my brother's car - both due do crappy oil. Saved both engines by getting an oil change IMMEDIATELY upon noticing the pressure drop.

No way that I'm putting an ammeter into a Ford product, since they tend to burst into flame quite well without the "outside help" of an aftermarket ammeter install. In any event, a voltmeter is much more useful than an ammeter, and WAY safer, per this article:

"Sharon Cooke" wrote in message news:mQ8Yh.108528$ snipped-for-privacy@newsfe22.lga...

I agree with the major points of the article. If you have a good voltmeter and pay careful attention it is very useful. However, the last few OEM voltmeters in vehicles I've owned only had markings at the extreme, so you had to "guess" where 14 volts was. One of my OEM voltmeters always seemed to drift higher on long trips, and this worried me. I thought it was some sort of alternator problem. I finally checked it with a real voltmeter and determined it was the gauge that was drifting. However, I don't suppose I could claim it was "faulty" since it was indicating a voltage somewhere between 11 and 18 volts, and it never got to the "red" on either end of the scale. I am very suspicious of the voltmeter in my current Nissan Frontier - it never moves when the truck is running. Either this truck has a super duper alternator, or the voltmeter is also a computer controlled gauge. I can't tell from the wiring diagram since the wiring harness just disappears into the IP module. If you really want to know what is going on with your electrical system, having both a voltmeter and an ammeter is better than either alone. With the voltmeter, you know the "pressure" in the system, with the ammeter you know the "flow" to and from the battery. If you have a good alternator, the voltmeter is always going to be in the 13.5 to 14.5 volt range with the vehicle running unless there is a major problem. If you also have an ammeter, and it shows significant current draws, even when most accessories are off, then you know you have a problem.

The article is wrong on one point - you don't have to run all the wires through an ammeter in your dash. There are remote sensing ammeters where the only thing transmitted to the gauge is an indicator voltage. You might want to look at

for an example of how this works. My old 800 Ford Tractor had an even simpler sort of ammeter. It did run the main power lead through the ammeter, but there was no physical break in the power lead. The ammeter had a loop that the main power lead ran through and this "detected" the current flow. With modern vehicles with scores of circuits this is impractical, but a remote senor like shown in the example on the web page can be applies at the main batter connection and transmit an indicator voltage to the dash gauge. Ed White

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I come from the world of heavy commercial truck repair. Never seen a pressure gauge or hose dump oil behind the dash. The electronic dashes use transducers that cost $15 from the dealership and rarely fail and are always accurate within 2 or 3 psi when checked against my mechanical gauge. I have seen one inaccurate transducer; owner brought it in for low oil pressure. Everyone else who complains of low oil pressure needs an overhaul. Most drivers are too stupid to know what is or isn't good oil pressure, and I see quite a few drivers dump that lucas shit in the engine to get the psi higher. But I don't think that's a good argument to use an idiot light over a real gauge. I do not know of any commercial truck makers that equip $20,000 engines with just idiot lights. All of the recent gauges are however equipped with an idiot light in addition to the needle. Comes on with low pressure, loss of signal, or excessively high signal. LED "bulb." Seems to me an optimum compromise. Needle for drivers who read the book, light for drivers who don't. Granted, it's a different market, where engines do routinely wear out simply due to mileage and most drivers do not own the driven vehicles. But direct-reading gauges aren't difficult or expensive.

I knew someone that thought the oil light was supposed to be a reminder to change the oil.

Or how about a low oil level indicator. True story: A long time customer had an early 70s Buick. Very well maintained, high mileage. As was common on Buick engines of that vintage, the oil pump was weak and the oil lamp would flicker at idle on hot days. He gave the car to his 30ish yo son. After a few weeks, the son brings the car in pouring oil from every opening and barely running. I drained 7 gallons of oil out of that engine! When the oil light would flicker, he would add a quart or 2 of oil. He "estimated" 2 quarts at a time by the amount of oil running down his driveway!! The father was such a smart man and well informed customer, he was a retired Steelworker. The son had a Masters in Electrical Engineering. Go figure!

my sister added some oil whenever the idiot light came on.

she blew out a head gasket on her fox..

Please bring back *analog* gauges...

They are not that hard to read.

What makes you think she would have done any different with a gauge?? Very possibly she would not have noticed the problem at all with a gauge. At least with a light there's something bright and shiny to attract their attention.