I have a 2001 Fleetwood Southwind 35R, 6.8L Trition V10, on the F53 motor home chassis. I have the Scangauge II and yesterday while in stop and go traffic with air temperature in the upper 80’s it gradually showed 182 degrees and only cooled down to around 175 to 177 after traffic started moving again. Normally it is around 160 to 165. Never seen it go this high before so I am concerned, what is the danger point and best way to cool it down? Engine temperature was running between 190 and 198. Have never had the clutch fan come but have never seen the engine temperature over 200 either, my other RV would kick on at 210 degrees.
100 degrees above outside temperature is nothing to be concerned with.
Short periods of time above 200 is also ok. If the transmission stays
above 200 then the fluids life will greatly be reduced.
Below is something I copied off the internet sometime ago...
OIL TEMPERATURE MEASURED AT CONVERTER OUTLET TO COOLER:
The maximum allowable temperature. This is the recommended place to install a temperature gauge or sensor. Do not allow the converter outlet temperature to exceed 300° F. The temperature at this location will vary significantly because of load, hill climbing, etceteras. If the temperature reaches 300° F, reduce throttle. To lower transmission temperature with transmission in neutral, run the engine at 1,200 RPM for at least 2 - 3 minutes while keeping a close check for signs of engine overheating. A transmission in a heavy throttle, stall condition (a typical situation is rocking a vehicle stuck in mud, sand, or snow), may increase temperature at a rate of 1° degree per second of stall.
OIL TEMPERATURE MEASURED AT OIL PAN OR SUMP:
The minimum operating temperature. Note: It is possible in low ambient temperatures to overcool the transmission with auxiliary oil to air coolers. Oil to water coolers in standard factory radiators will normally not overcool a transmission.
Normal pan oil temperature operating range.
Maximum allowable oil pan temperature for short durations during long hill climbs.
Damage occurs to internal transmission parts, including warpage of metal parts, degradation of clutches, and melting of seals. Transmission oil oxidizes, (forming varnish-like substances causing further clutch slippage and compounding heat build up) and transmission oil life is extremely short.
AUTOMATIC TRANSMISSION FLUID LIFE / TEMPERATURE RELATIONSHIP:
Automatic transmission oil can provide up to 100,000 miles of service before oxidation requires replacement, at an operating temperature of 175° F. Above this temperature, the oil oxidation rate doubles with each 20° degrees F increase in oil temperature. See chart.
DEGREES F MILES DEGREES F MILES
175 100,000 295 1,500
195 50,000 315 750
215 25,000 335 325
235 12,500 355 160
255 6,250 375 80
275 3,125 395 40
Note: Transmission oil and filter should always be changed more frequently when driving with heavy loads (RVs), typically at least every 25,000 mile intervals, since converter outlet temperatures then normally far exceed the ideal 175° F.
Best way to cool it down is by driving at speed. I have a 2000 F53 with the 4R100 tranny with a temp gauge in the cooler line. The hottest mine gets is when it has been pulling a hill or driving at speed and I have to slow down for roads or traffic. Extreme hill pulling, over a mile at 40mph or less, will get it up to 180-185 but with continued driving it will stay there. Normal driving it stays around 160. Never gone above 195 round trip from Texas to Alaska and back. That's with Mobile synthetic tranny fluid.
* This post was
edited 08/18/12 09:41pm by garym114 *
2000 Sea Breeze F53 V10 - CR-V Toad
Some RV batteries live a long and useful life, some are murdered. Get a Digital Multimeter and Learn How to Use It
We have the very same motor home that you do, and we also have a Scangauge. The temperatures you are seeing are very close to what we experience. Our engine temp typically runs between 190 and 198, and our transmission temp is typically around 165 on level ground and goes up to around 180 when climbing grades.
Our former 2000 Dutch Star Gasser with the same drive train ran at roughly the same temperatures.
Roland and Elaine
2003 Newmar Kountry Star 3904 Diesel pusher
CAT 3126 330 HP with Allyson transmission
2004 Chevy Tracker LT V6 4WD
Roadmaster Sterling tow bar