2019 L5P First Problem
My truck and gooseneck trailer loaded weigh in at 25,000 lbs. truck will pull this load as fast as I would want to go, but to slow the fuel burn rate down I set the cruise at 60 hit tow/haul and let her eat. Going into North West Arkansas there are a couple of climbs that 18 wheelers have issues with that drop their speeds from 65-70 mph down to around 35-40. I know that these climbs are out there but in my mind my truck is smart enough to know when to down shift or help itself out, correct? Truck has done fine going the first 20-25 miles up hill with out any real problems speed is at 60 mph, tach setting about 1700 rpm, engine temp according to CTS is 200 degrees trans is about 190 degrees. Going up this long climb about half way up dash lights up and says "A/C turned off", I look at all gagues again, engine at 210 tans at 190 oil pressure is about 30 psi 5th gear 1700 rpm 60 mph, so I think well the truck is thinking for its self lets see what happens now, about 1/2 mile later dash flashes "Reduced Engine Power" and I'm like what the heck, recheck gagues and engine is at 250 and climbing, trans at 200 oil 30 psi still in 5th gear 1700 rpm and 60 mph, about 200 yards to hill top so I just let it eat to the top, as soon as I crest hill engine temps starts to drop, on the down hill run of about 1-11/2 mile temp goes back to about 220 everything else is the same, start up next hill about a 1 mile pull the temp starts to climb to 240 and then I get the "Reduced Engine Power" message, top out at 240 kick cruise off and drive the rest of the way using the foot feed never over 60 going down hill with grade assist on and never over 2200 rpm on any other climb??? Had truck to dealer today to check for codes and they could not find any (which is what I thought would happen) anyone got any ideas???
Sorry this is so long but want to get as many of the details in as I could.
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