I have installled and Edge Evolution on my 04. In reading the spreadsheets from bismic I understand that the TFT reads 30 degrees lower than it actually is. Is this correct? Not that I doubt bismic but I want to insure that I read the spreadsheets correctly. The evolution gets all of its readings from the OBDII port except EGT. Thanks!

 

You have couple of things going on against you when you use a digital gauge.

A. The placement of the sensor itself by Ford is not in the best of places to get the most accurate reading.

B. Like everything else, it's electric and it has to go thru alot of wire and encounter alot of resistance, which will drag it down a little bit as well(this is negligible, but when you couple both together, it could amount to a good bit).


I have run both types of gauges at one time or another and the digital one was lower in everything that I got from the OBD-II that I had a corresponding analog gauge for. As long as your aware of this and now by how much, it is easy enough to compensate for.

 

Is a lower reading true for the coolnt temp as well? The ECT is consistantly running at 190 to 192, a little over 205 on hills pulling my 5th wheel.

 

Was it lower... yes, but it was more negligible as it was 2-4 lower(dependant on ambiant temp, loaded or unloaded etc., but it always managed to stay within that range of "error"). What was the ambiant temp, speed traveling, and time on the road when you go those readings?

 

On the ECT's the high numbers occured pulling the 5th wheel up an incline on the highway (60-65) as soon as I got to the top it went back down to the low 190's. Temp outside was 80-85 with relatively high humidity. The number I am most concerned with is the 190-192 consistantly. It always runs at that range pulling or not and regardless of speed or outside temp.

 

I wouldn't be worried about that. When you add in that 2-4 degree error that puts you right at my average temp when I'm driving respectible with my tow tune on(my tow tune would probably have the same hp power rating as people's general street running stock turbo and stock injectors). 215-220 is where I would definately be concerned with. 210 I start to be concerned, but 196(including the high degree of being off just to be on the safe side) I wouldn't be.

 

Thanks Tex. Now that I have access to all this information I tend to get "over sensitive" to the readings.

 

The spreadsheets are an accumulation of much of what I have read, most of which I reference the source. With regards to gauges, this was one area that I had to take from others since I do not have any aftermarket gauges or sensors - yet. I would certainly say that 30 degrees may not be exact, but there sure is a significant offset. Several past "posters" supported an offset up to 30 degrees. Tex 25025's reply is one based on experience - he is the main source for most of my gauge and tuner info (thanks tex).

In the last few months, I have found a few things that were not quite exact in the spreadsheet - minor things, in most cases I was too conservative. I am continually refining them and I would suggest you do too and make them your own reference material.

One thing I found recently was with the transmission temperature. On another website, a former Ford transmission engineer stated that the transmission fluid can take a lot higher temperatures than what most would expect. He said it could take over 250 degrees F. I did some research and found that seals may begin to harden at 240 - but probably not significant with very short exposure. My spreadsheet stated that 220 was too hot and the tow/haul would flash at 230 degrees. I have since discovered that the 230 degree "tow haul flash" was wrong.

After quite a bit of recent "research" help from PowerstrokeHD (big time thanks!), he provided some Ford reference info that stated the tow/haul light would begin to flash at 275 degrees (not 230). This seems to indicate the tranny could take high temps for short periods, although I would NEVER run past 240 (really even 220) if I could help it.

In summary, you will get lower readings from a digital TFT readout than with analog, but as tex states, compare for yourself and compensate as required. The key thing is to watch for changes and know the danger points.

 

Thanks for the detailed info bismic. I will use the numbers now as a "baseline" and track any significant changes that occur.The TFT #'s I am getting right now are in the 140's even pulling my 5'er. I just wanted to ensure I was reading the spreadsheets correctly and make sure that I didn't have any current issues as I move forward.

 

Tranny temps and how hot can one go before the tranny does is definately a hotly debated topic. I tend to be on the conservative side as most people know that I had tranny with burned servos and some scary moments at intersections because of those burned servos. Since then I'm a firm believer in gauges(rather tuned or not as that truck was not tuned) and I really make sure I try to run cool with regard to tranny temp. The tranny oil that is used in the torqshift can take more, probably alot more, then what I tend to keep it at(as far as my defination of hot levels to tow at).

 

Yes, it can.

Modern trans seals don't have ANY problems until they are over 300F. They can run 240F all day and all night with NO hardening.

That's correct.

 

Thank you for the reply Mark.

Like Tex25025, I will be very conservative with my truck also. If I have never run above 200 and then, for an unknown reason, it excedes 220, I will not run it unless I have no other choice. Something unexplained, generating more heat than expected, will cause me to shut down and investigate..... unless I am out in the middle of no-where. Then, I will slow down until I can get it looked at.

Regardless of your conservatism, it is good to know the real limits.

 

Just for referance for the OP. I just got back from a 700 mile round trip and my trans temp range was between 140-175. This was at 75-80 mph and I was running unloaded. My truck ran perfectly so I am happy. Hope that info. helps you out.

Sarge

 

Mine hasnt gone over 200* since i have had the Autometer tranny temp guage. Highest i have hit was 195* while backing a 13.5k 5th wheel camper down a long driveway. I too like to stay on the conservative side, but when i would read those low numbers for what was considered too hot for the torqshift and then get in my dad's 06 d/max and the redlines on the tranny temp didnt start until around 270 it always made me wonder why the torqshift's were soo low. Now that i see the light flashes at 275*, it puts it on par with the allison.

 

Don't sell the allison that high. I had a friend that had the allison tranny and he had his tranny totally fried and his tranny didn't even redline.