I have a 04 Dodge dully Cummins with a 6-speed manual trans, and I haul a 18k lb fifth wheel trailer with it. I have a guage for the EGT's, but I'd like to know what are the maximum recommended temperatures I should ever see on my guage when hauling? (What is the maximum temperature for consistant driving?; what is the maximum temperature for a temporary period of time?) Thanks.

 

I have a friend who was a engineer at the Cummins engine plant. He told me the engine is rated for 1350* at max engine speed for 10000 hrs. It will handle higher temps for a short period of time. So I guess to answer your question, the max "safe" temp would be 1350* all day.

 

I''m much more conservative than that!

Good post on towing forum on EGTs below.
https://www.dieseltruckresource.com/...g-t255404.html

I down shift to keep my pre-turbo EGTs around 1100-1150. With my 5 speed and 13.5K 5er in 100 degree temps, I usually cruise up the grapvine in SOCAL (long 6% grade) in 3rd at 35-40MPH, EGTs around 1000 and I think RPM around 2300. In 4th RPMs drop below 2000 and EGTs quickly go over 1200 as the engine starts lugging.

BTW I use the Smarty standard 5 setting with my SO...seems best setting to keep EGTs down.

 

Early 04 or late 04?

03-04 should be in the realm of 1250* max continuous.
04.5-07 should be 1375* max continuous, and up to 1450* for short spurts (like hills and such).. In fact some sources say 1450* is max continuous stock.

 

My truck is a Late '04' model.

 

Stock fueling should be fine, regardless... should...

You can do things like improve intake/exhaust flow (wont net you any power, but may drop the EGT's a few *).. I like the Airaid MIT (keeps the best parts of the stock system and replaces the worst), and a cat delete...

If you want a little oomph and lower EGTs the Smarty Jr is the way to go.