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I received a PM question about the operation of the auxiliary guage package on an 04 SSR, and thought I would reply to it publicly so that everyone benefits and we can discuss.
The question asked if certain apparently unexpected behavior is normal. It is!
This includes the following:
- The guage package for the 03 and 04 is different than on the 05. The 03/04 package displays voltage, Gallons per hour (yes, per hour), and transmission temperature. The 05 substitutes a current "torque" readng instead of the GPH. Bizarre? Yes.
- The voltage guage does indeed normally read what seems "high". I suspect this is because it reads the raw alternaotr voltage, not the battery volatge.
- The GPH guage operation seems strange until you watch it for a while (NOT while driving!!). Then it makes sense. It is NOT displaying "instantaneous" GPH. That would have the guage moving ALL the time over a very wide range of readings! Instead, it samples the actual GPH for a period of "x" seconds and then abruptly moves the needle to display that average value. It displays that average value until a new value is available to display after another "x" seconds. That way, it is actually readable by a human. It is NOT intended to display your instantaneous fuel consumption, but rather your "current" fuel consumption rate. So, for example, use it as a quick verification that you are indeed hearing louder engine note because you are going into a strong headwind at 70 mph, and fuel consumption IS higher!
The GPH reading at idle looks like "no" reading, but it is actually just a "very low" reading.
- The transmission temperature guage is intended to warn you if your transmission is starting to run hot under the current circumstances, as high transmission temperature is what actually severely degrades the life a an automatic tarnsmission. If you pull that 2500 maximum allowed trailer for example, into a headwind, or in the mountains, expect to see some movement upward.
The operation of this guage MIGHT appear at times to be strange, with it sometimes showing a low reading (say 10 o'clock position) and sometimes a reading right at the 12 o'clock position. In most cases, it is real. The difference is that in stop and go traffic for example, or at high highway speed, it will be closer to 12 o'clock,a s the transmission IS really handling some load. When the vehicle is cold, or the speeds are low and steady (city at 6am and no traffic), the reading will be low.
Note that after changing my rear axle ratio from 3.73 to 4.56, there is NO detectable difference in transmission temperature. This makes sense, as regardless of the relative rpm versus torque at that rpm combination, the net WORK done is the same, and it is the work done that generates heat.
One more thing. If your guage package displays voltage, but NOT GPH or transmission temperature, that means that the installer accidentally shorted the package via improper installation. The package must be replaced, The reason you still get the voltage reading is that that reading is straight from the vehicle and unaffetced by the destruction of the circuitry for the other 2 guages. The short circuiting is apaprently very easy to do, according to the service writer that told me that a Chev dealer mechanic had shorted mine, and replaced it under warranty.
Jim G
The question asked if certain apparently unexpected behavior is normal. It is!
This includes the following:
- The guage package for the 03 and 04 is different than on the 05. The 03/04 package displays voltage, Gallons per hour (yes, per hour), and transmission temperature. The 05 substitutes a current "torque" readng instead of the GPH. Bizarre? Yes.
- The voltage guage does indeed normally read what seems "high". I suspect this is because it reads the raw alternaotr voltage, not the battery volatge.
- The GPH guage operation seems strange until you watch it for a while (NOT while driving!!). Then it makes sense. It is NOT displaying "instantaneous" GPH. That would have the guage moving ALL the time over a very wide range of readings! Instead, it samples the actual GPH for a period of "x" seconds and then abruptly moves the needle to display that average value. It displays that average value until a new value is available to display after another "x" seconds. That way, it is actually readable by a human. It is NOT intended to display your instantaneous fuel consumption, but rather your "current" fuel consumption rate. So, for example, use it as a quick verification that you are indeed hearing louder engine note because you are going into a strong headwind at 70 mph, and fuel consumption IS higher!
The GPH reading at idle looks like "no" reading, but it is actually just a "very low" reading.
- The transmission temperature guage is intended to warn you if your transmission is starting to run hot under the current circumstances, as high transmission temperature is what actually severely degrades the life a an automatic tarnsmission. If you pull that 2500 maximum allowed trailer for example, into a headwind, or in the mountains, expect to see some movement upward.
The operation of this guage MIGHT appear at times to be strange, with it sometimes showing a low reading (say 10 o'clock position) and sometimes a reading right at the 12 o'clock position. In most cases, it is real. The difference is that in stop and go traffic for example, or at high highway speed, it will be closer to 12 o'clock,a s the transmission IS really handling some load. When the vehicle is cold, or the speeds are low and steady (city at 6am and no traffic), the reading will be low.
Note that after changing my rear axle ratio from 3.73 to 4.56, there is NO detectable difference in transmission temperature. This makes sense, as regardless of the relative rpm versus torque at that rpm combination, the net WORK done is the same, and it is the work done that generates heat.
One more thing. If your guage package displays voltage, but NOT GPH or transmission temperature, that means that the installer accidentally shorted the package via improper installation. The package must be replaced, The reason you still get the voltage reading is that that reading is straight from the vehicle and unaffetced by the destruction of the circuitry for the other 2 guages. The short circuiting is apaprently very easy to do, according to the service writer that told me that a Chev dealer mechanic had shorted mine, and replaced it under warranty.
Jim G
