Truck ran warmer...

[MMeier]

... on this last trip to Oklahoma and back! Needle was about 3-4 needle widths above 200* for a fair amount of trip, Even last night coming across NM at 66* ambient the temp was still above 200. Lighter load then usual too. Radiator is clear of excessive "junk", seems to be running fine also. Can't hear fan kick in RPM wise as I could before, does seem to work when A/C requires it too(low speed, stop and go, etc. )Soooooo, is there a seperate "control" for temp or is it just a matter of the fan clutch itself going south?? Radiator was recently serviced.

 

[JJ Jackson]

MMeier, 2nd Gens radiators get plugged on the fan side with oil being flung from the crankcase vent puke bottle. Dirt sticks to it the eventually plugs the radiator. Since no air gets through, the fan clutch never sees the high temp and therefore never kicks in. I wonder if 3rd gen trucks have the same problems?... ... Jim

Sorry, I didn't realize I was in the 3rd gen forum, my bad.

 

[bgilbert]

Radiator and overflow filled up ? You mentioned the radiator was serviced recently, what percentage is your antifreeze? You may have too much antifreeze and not enough water or vice versa, ie too high % or too low %.

 

[roperteacher]

Mine ran a FRACTION warmer today . . maybe the width of the needle past where it usually does... . Normally it runs just under the 200 no matter what. . I was pulling 4 horses, steel trailer and going 70 over the mountains. . go figure. .

 

[MMeier]

Yep Bill, both always filled, running about 45% anti, 55% water(distilled of course!) Just made this trip 2 weeks ago with about 5500 more # behind me and the outside temp was about 10-15* warmer that trip. Like I said in my first post, last night the temp was only 66*in NM and no A/C going either and the temp gauge was a shade over 200*, has never done that before. :{ Tonight after unhooking my stack of trailers and driving home the temp gauge was back down to its normal reading of about 2 or 3 needle widths below 200*, where it has usually been most of the time since new. And I could hear the fan clutch kicking in off idle seeing as how I had the A/C going full blast ! So is something preventing the fan clutch from engaging at speed or ??

 

[bgilbert]

MM, well Chrysler from the start of time has been known to have some funky gauges. I'm not sure how your 3rd gen gauge looks, but if you hear the clutch kicking in during slow speeds, AC on, I wouldn't be too concerned with it. Could be a bad gauge or sensor not giving you the correct temp. If you had another water temp gauge there to verify, the engine probly wasn't running 200*f. Then again, maybe your thermostat is going bad. Might find out if Cummins has an updated 160* t-stat. Could have air in the system too. Cummins hasn't gone to egr yet have they? If so, egr engines run damn near 200* most of the time, when worked and loaded.

 

[MHirst]

I have a 05 Cummins with the auto, I recently remodeled the exhaust to allow the truck to breath, the cat on the new trucks seems to be a little restricted anyway after the mods the truck runs right at 185 empty then jumps up tp around 200 to 210 loaded pulling trailer over the mountains, seems to be normal to me it always cools right off when I level out, by the way the performance is a lot better now.

 

[MMeier]

Was thinking along those lines too Bill, gauge and/or sender going bad. Just not used to seeing it run that hot/warm. Have made this trip perhaps 25 -30 times in the past year and never saw it go that high. Driving around here this morning, saw right below 200* as used to be 'normal'. Bug screen cleaned ( same screen thats been in there for well over a year), nothing to inhibit airflow across coolers. Maybe I'll just go down and buy a new sender if it's not too expensive, maybe a T-stat also, oh well!!

 

[GShail]

I have a similar problem with my truck, wierd fluctuations, goes hot and then stays hot