Bryan wrote:

The short answer- I have overheated  the Ford once.


The very long answer  (delete if you wish)

I have only had the red light on once on the pickup truck and that
was with the travel trailer ( gross combination weight 13,000 lbs).
We were in Nevada up in Bristlecone pine country around 9 to 10,000
feet above sea level.  As it is a park we where moving
very slowly up a hill with the air conditioner running ( a
significant
additional load on the cooling system) when the red light came on.
     When I am hauling more weight with the pick up  I usually
avoid summer travel just because of the overheating worry.
Just  for information  current production semi tractors up here are
often 525 hp.  Some are  up to 600 hp but the 600 has been
discontinued because of the EPA.  We gross 140,000 lbs winter and
summer on 8 axles and haul over grades that are typically in the 6
to 9 % range and a few spots up to about 11%. The bulk of US trucks
are 80,000 lbs gross weight on 5 axles. 11 western states are
members of the heavy haul compact and allow higher weights on more
axles.  There are a few other states that allow more weight on more
axles but by far and away the majority of the trucks you see every
day on the interstate will be the 5 axle
80,000 lb  tractor with single semi trailer.
       Heavy truck radiators today are about 2/3 the size of the
rads
found in trucks from the mid 80's .  Air to air heat exchangers are
in front of the rad and used to cool the charge coming out of
the turbo charger.  The cooling systems also pump far less
coolant than the old systems.  Turbo boosts run around 25 psi
( one race truck application was running 100 psi out of twin turbos
but had trouble with the stock after cooler housing exploding...
I guess he exceeded the design parameters. )    Bryan  in Princeton
B.C.  - leaving soon to take my semi to Texas

Thanks Bryan more good data and evidence on figuring out what is
going on with our cooling systems. It is hard to find data on this
stuff as nobody publishes any useful information in the SAE anymore.

Paul Lamar
 
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