Okay, here is what I experienced this weekend when towing approximately 10,000lbs.
My pyro/egt dial shows a range from 0-16 (not like the other ones in 1000 intervals). When towing uphills with the overdrive off (light on) the gauge showed 6-7, with the overdrive the gauge showed approx. 8.5. The gauge start creeping up to 8- 8.5 when I was going uphill only, in normal highway stayed at 6-7. Now my boost gauge, uphill with overdrive off when up to 30 or so, but stayed up there for a few seconds and then it went down. The boost gauge shown on a flat range was from 5-15. The trans temperature stayed pretty cool until the stop and go routine, normally 160 at driving, stops go 180 and backing up with the trailer to a max of 210. I also noticed that when I used the overdrive off, my pyro/egt gauge stayed cooler even on hills (6-7). I had to use the overdrive off on hills or else I could not get high rpm's, with overdrive on and uphill 1100 rpms. With overdrive off went from 2000 to 2600 rpms. Should I keep using the overdrive off when going to hills to keep my rpm's high, or it does not matter. To keep my rpm's at least 1700 rpms I have to be cruising approximately 55 miles per hour with the trailer attached. Sometimes I could not keep that speed of 55mph and that was the time I had the overdrive off to keep my rpm's higher than 1700. Should I continue to use the overdrive off and on depending the rpm's the truck shows, or do not worry about the low rpm's because I can get up over 50 mph's and then my rpm's will go over the 1700.

 

wengerda, it sounds like you were getting it right. With that big of a load you will have to drop it out of O/D on the higher grades. I beleive you have the 2004.5 since your truck was built on 3/04 which means peak torque is 1,600 RPM so if you fall below 1600-1700 I would downshift or if you find that the tranny is shifting between 3rd and 4th(O/D) then drop it out of O/D as well. No problem with keeping the RPM's at 2,500 uphill, just keep an eye on your EGT's and you'll be fine.

Karl

 

What should be the normal range for EGT/Pyro gauge. Remember my gauge shows a range of 0-16 and not in the thousands like others. Thanks.

 

Anything above 13 (1300° F) I think you want to back off a bit.

 

my pyro on the gauge face goes from 0-16 [i have the autometer ultra lites] but if you read the small text on the gauge face, it shows x100 on the scale. same deal on your tach. it reads 0-5, but they are in x1000 range... and 1300°f is a good point to start letting off the throttle. i can get to about 1250°f on a hard pull, and i don't have any fueling mods yet...

 

Thank you for the information, I did see now the small letters of x100.