Mechanical vs Electrical oil pressure gauge?

[jvmoore]

I'm getting ready to put a set of Autometer Phantom series gauges in the 03' an I was wondering what the max oil pressure reading you fellows have had? I've heard that the oil pressure can spike over 120 psi @ start-up which eliminates the electric gauge. (I always worry about oil leaks in the cab with mechanical gauges)

 

[y-knot]

First off, congraduations for installing gauges and secondly for choosing AutoMeter. They are by far the best gauge manufacturer available, and offer many many different styles and types of gauges.

The oil pressure "spike" you referred to happens in every engine diesel or not. Usually found to happen in the cooler weather on start-up, and moreofften with the use of conventional motor oils. This spike, does no harm to the electrical sender, it simply shows up as a oil pressure to the maximum level. If anything the mechanical gauges would suffer the most, but most have a relief built-in.

I have been using Autometer for over twenty years, and have never had a single problem. Many of my vehicles were off-road or competition, and were not as protected from the elliments as those in my truck. The decission to use mech or elec gauges is yours to make, but I can tell you I have never liked using any gauges that allows oil,fluid,fuel,or high pressure gas to enter the cab. It is a risk that is completely un-neccessary to take, they create a safty danger from hot liquids, combustable fluids, and can lead to a very big mess if a line developes a leak.

With todays technoligy, there is no reason to not use electric gauges for the montoring of oil and fuel pressures and temps. I still use some mechanical gauges, Vacuum, Boost, and air pressure are a few. These are excellent choices for mech gauges and pose no danger to truck or personel. Your selection of the Phantom series gauges by Autometer is a fine choice, they make a large selection of both mech and elec gauges. Their 5704, Boost gauge is mech and will fuction fine, it gives 0-35 psi. The 5744 EGT gauge is a 0-1600 degree guage that will take care of any concerns you might have when it comes to Exhaust gas temperatures. And the 5727 oil pressure gauge will work just fine for the engine oil pressure. The factory uses an electrical oil pressure sender, and it functions just fine. The only problem with the way the factory chooses to monitor the engine oil pressure, is they set up a paramiter and as long as it see's at least 6 psi, it figures everything is just fine. The gauge in the stock truck is not based on oil pressure at all, it is simply programed to give a reading that most owner would find exceptable, sound stupid but it's the truth. One of the main reasons I decided to install a oil pressure gauge.

 

[Rams-n-Hogs]

The factory uses an electrical oil pressure sender, and it functions just fine. The only problem with the way the factory chooses to monitor the engine oil pressure, is they set up a paramiter and as long as it see's at least 6 psi, it figures everything is just fine. The gauge in the stock truck is not based on oil pressure at all, it is simply programed to give a reading that most owner would find exceptable, sound stupid but it's the truth.

Y-knot,



I had heard this, too, but I'm not real clear on it. I was watching the gauge today as I was driving my truck, (the 2004), and it acted exactly like any other oil pressure gauge. When the truck was hot, (and the oil thin), the pressure dropped whenever I stopped, and went up whenever I started moving again. It doesn't make sense that DC would make the gauge act real if it's not actually based on oil pressure. At worst, I can see them programming the light to come on, or a bell to chime, or something, if the gauge doesn't see at least 6 psi. Does your gauge read different than the factory one? I'm new to these computer controlled trucks.



Jim

 

[y-knot]

Well it's suppose to act like any other oil gauge, that was the intent of the program. As long as the oil pressure from the engine sensor is in the defined paramiters of the program, it should read in the area that most consumers would deem normal. The reason for all of this, is to limit the number of complaints , manily those woory warts that would come in to the dealer everytime the gauge read lower or higher then what they are use to seeing. In the cold, you will have a higher then normal oil pressure at start up. In the heat of summer, the oil pressure may drop a bit. These normall swings in oil pressure are exactly what they (Dodge) want to remove, this elliminates a very large number of service calls, which get very expensive. The computer, looks for a minimum of oil pressure. It then takes in consideration the engine water temperature, and outside temperature, and computs a oil pressure that the normal opperator of the truck would expect to see for a reading, this is what your stock oil pressure gauge will show. If you take the time to install your own oil pressure gauge, then you will see real time pressures and there fluxuations. From my observations, there is plenty of oil pressure, I just like to know what is happening as it happens. Yes if you depended on the stock gauge for accurate and real time reporting, the damage from low oil pressure would be done before you ever realized their was a problem.

 

[Forrest Nearing]

I run mechanical gauges whenever possible... less stuff to go wrong.



I will say that the copper line that I used to plumb my oil pressure gauge transfers a lot of noise, but I like knowing what's going on in my engine!



Forrest

 

[rbattelle]

Y-Knot is a wise man, and he speaks the truth. I have an electric oil pressure gauge installed (0-100 psi), and I can say for a fact that it's rare for the factory gauge to read a pressure similar to my gauge and in those cases it's meerly a coincidence.

 

[Rams-n-Hogs]

y-knot,



Thanks for explaining that. I plan on installing an oil pressure gauge anyway, but it also looks like my gauge works exactly like it's supposed to. It looks like real-time readings and fluctuations. I just can't understand DC programming the gauge to do that. That gauge shouldn't even be hooked to the computer. The 12V's aren't set up like that, are they? That would mean I need another gauge for my '96.



Jim

 

[Kirwin]

Max Oil Pressure

I like the Cyberdyne gauges. My max oil pressure is around 80 psi at startup cold just prior to shifting. (Note that it doesn't get that cold here in Virginia) At hot idle, just pulling off the interstate oil pressure can drop down to 6-8 psi. It will slowly rise over the next couple of minutes to 12-15 psig. I run 5W-40 Valvoline Premium Blue Extreme. As a comparision my 97 never drops below about 18 psig using the same oil. My oil pressure sender for the gauge in the 03 taps into the main oil rail right by the left motor mount (vice the oil filter location) same as the factory sender.

 

[rbattelle]

y-knot,



Thanks for explaining that. I plan on installing an oil pressure gauge anyway, but it also looks like my gauge works exactly like it's supposed to. It looks like real-time readings and fluctuations. I just can't understand DC programming the gauge to do that. That gauge shouldn't even be hooked to the computer. The 12V's aren't set up like that, are they? That would mean I need another gauge for my '96.



Jim

Dodge's programmers have worked their magic and fooled you into believing your factory gauge is real. It's not. I don't know why people think it would be "so much trouble" to program the needle to dance like it does... an algorithm to do this would probably be just a couple lines of code. Anyway, 12v's are not like this... back then they had a real gauge.

 

[Dkuhlman]

Dodge's programmers have worked their magic and fooled you into believing your factory gauge is real. It's not. I don't know why people think it would be "so much trouble" to program the needle to dance like it does... an algorithm to do this would probably be just a couple lines of code. Anyway, 12v's are not like this... back then they had a real gauge.

I thought the 12Vs simply read mid-gauge anytime there was acceptable oil pressure present. At least my '94 did. It was a constant 40 psi on the gauge anytime the engine was running, hot or cold, idle or fast.



My '02 24V actually moves a little but, as most have said, probably isn't a true reading either.

 

[Forrest Nearing]

my factory gauge on my 12v hovers right around 42psi while I'm cruising down the highway... my aftermarket mechanical gauge hovers around 70psi while I'm cruising down the highway...



when I first start it up, I'll peg the 100psi gauge at 1800rpm... the factory gauge is still showing 42psi.



maybe the 1st gens had a real gauge, but my truck doesn't.



Forrest

 

[rbattelle]

Oops! I stand corrected. I was honestly under the impression that the 12v trucks had a real gauge, and that the el fake-o unit didn't come into play until the 24v trucks. Sorry about that!