2010 freightliner century 120 class is consuming engine coolant AF ,checked the hoses ,tank ,pump ,radiator and find not a single drop of cooler , please advise.

well that is its A#1 job to do just that every cool down cycle even on a brand new car.
not told you how long it takes the fluid to drop 1 day ,1 year? or?
but if the engine eat the coolant AF. then the RAD leak down test finds that. (a tool)
most cars we se the Reservoir to 1/2 full.
and goes higher hot engine and back to 1.2full cold
if engine fails (or any leaks of any kind any where)
the level drops, telling any tech or owner there is a very serious problem.
the tool
https://search.brave.com/images?q=radiator+leak+down+tester&source=web

what a tech does if lots spare time
is open hood get engine fully hot 1/2hr driving . (15psi)
and look for leaks. here is short list (ASE basics all)
new cap is best for $5 and holds 15psi and no longer leaks (cap)

1. AF to ground leaks, seen. (AntiFreeze 50%)
2. hoses all leaking AF.
3. leaks to passengers toes ,heater core leaks.
4. leaks from intake manifolds for sure V6 or V8 engines
5. core leaks block or heads. (aka freeze plugs)
6. the tail pipe has steam all the time running (cloud)
7. the head gasket viewed at sides, leaks.AF
8. RAD leaks (all of it) even squirts to places not leaking oops.
9. water pump leaks.
10. engine oil pan shows oil , is milk chocolate. oops super bad.
11. A/T TRANS SAME , HAS AF MIXED IN TO ATF FLUID. RAD COOLER BAD .
12. THOSE ARE SIGNS. OR USE THE PRESSURE TEST TOOL.

best see the leak,as old signs of leaks can lie you, yes leaks but was a squirted to leak ,not THE leak. source.
watch leaks live hood up, and win.
best is not drive this car too far. (circle the block test to get 180f coolant temp?) and cause full pressure to find leaks for free.

well even the worst WE CAN BLEED IT OUT BUT IS TEDIOUS.

bubble always float up (rule1)
so we open up the highest hose in the coolant loop.
and put a funnel there.
my old jeep was one of the hardest on earth to do.
The silly jeep book manual says jack front of car up 4 feet, wow.
dead cold engine never hot. (generic first)
1: rad cap off
2: leave it off and add coolant dead cold only and add 50%AF
until fully full,
3: key on start engine (2 persons best) and 2nd adds 50%AF as it drops and 2nd person says ,STOP and I key off, ( engine run less than 5min or if rad neck cap off shows fluid starts to overload. we Stop;. ( I chock front wheels doing this) go easy run short times engine , not long, avoid natural engine heat , even 30second runs at first. OK done, it is now expanding, AF>
4: cap back on off, and still cold (ish).
5: now the remainder, (air pockets)
6: is add a funnel to end of one TOP hose. and hang the hose off the top hood latch loop (small rope ;twin)

then fill it up to full that hose. with 50%AF. and start engine
maybe 10 times or less until it will not take any more AF !
run engine say 1min max each try. ok its fully (cross fingers)
7: Ok done here.
8: now fill side bottle 1/2 full. AF
9: LAST , EVERY MORNING CHECK LEVEL AT THE RAD CAP OFF
AND ADD AF EACH TIME. EACH DAY UNTIL NO MORE DROP


---------------------------------OR SKIP ALL THAT----------Grin----------
AND USE THE VACUUM WAY.
WE HAVE SHOP AIR AND WE HAVE THE VACUUM, PRESSURE EDUCTOR DEVICE FOR RAD FILL.
IT SUCKS THE NEW AF IN TOTALLY ALL AT ONCE.
EVERY DROP.

https://www.amazon.com/ADAFIRST-Radiator-Automotive-Universal-Motorcycle/dp/B09YTNML6G/ref=sr_1_7?crid=3ILU143R6JKNY&keywords=Coolant%2BSystem%2BRefiller%2BKit&qid=1663858300&s=automotive&sprefix=coolant%2Bsystem%2Brefiller%2Bkit%2Cautomotive%2C85&sr=1-7&th=1

GOOGLE
ADAFIRST Coolant Vacuum Refill Kit, Cooling System Radiator Vacuum Purge & Fill Tool Kit

leaks at the EGR unit , inside at the heater unit , welsh plugs , cracked radiator tank, hoses , corroded cover behind water pump , water pump seal
check oil and if grey , timing cover corroded
have the system pressure tested to find the leak

1 - Radiator
2 - Thermostat housing
3 - Radiator bottom hose
4 - Viscous fan
5 - Water pump
6 - Radiator top hose
7 - Heater return hose
8 - Coolant supply hose
9 - By-pass hose
10 - Radiator bleed (purge) hose
11 - Bleed (purge) hose, thermostat housing
12 - 'Y' piece ejector
13 - Expansion tank
14 - Heater rail
15 - Heater unit
16 - Heater feed hose
17 - Intercooler
18 - Air cleaner
19 - Air feed hose
20 - Turbocharger
21 - Charge air supply hose
22 - Cooled charge air supply hose
23 - Exhaust manifold
24 - Engine oil cooler
25 - Feed pipe, engine oil cooler
26 - Return pipe, engine oil cooler
27 - Oil filter

Better ask Freightliner.

Freightliner CENTURY CLASS 120 Hood Parts ' TPI

truckpartsinventory.com > Hoods > Freightliner
Freightliner Century Class C120 BBC Fiberglass Hood Shell. Fits Models from 1997-2002 with Old.. ... Shell (Economy). Fits 2002 - 2004 Models with New.

Search Results Freightliner CENTURY CLASS 120 Hood on ...

https://www.heavytruckparts.net/search.php?...FREIGHTLINER...CENT...
Active Truck Parts Hood FREIGHTLINER CENTURY CLASS 120. More Info ... HoodFREIGHTLINER CST120 CENTURY, 2002, 1FUJBBCG92LJ79765, Hood

all happend over night, or what? parked a year.? or?

a daily driver? or a victim of bad service procedures, just came back from a tuneup??



no scan tool? , to see DTCs thrown, my guess,,, overheated. DTC.

fan belt not loose or fell off and gone?

lost fluid (sort time):

1: overheating

2: bad head gasket (or worse cracked head or block)

3: A/T tranny, the cooler is pushing AF in to the ATF

cooler bad, and coolant is pushing to the trans pan oil

4: AF fluid on passenger toes, heater core leaks.

there are many test for hits.

did you check for 50%AF protection using the $2 tool? every fall

if not and not living in KEYWEST, you can crack any engine block or head or both, so dont forget that. most places in USA can freeze

the tests:

engine or A?T oil on dip sticks look like chocolate, milk shake? oops.

overheating, the gauge show it.

the rad leak down test, tool fails.

the read exhuast guesses in rad neck tool

easy:

new thermostat, not put in backwards.

make sure both big hoses are hot on rad, if not the pump impeller fell off.



question

dead cold engine, check the rad lever. in the next first

and fill it with 50%AF. if not.

that is full, the side tank can fail (tube inside drops off)

then does it puke out? in 15min.

oil in the radiator is from a failed transmission oil cooler that is in the radiator tank. You will also have water in the transmission oil as when you shut off the engine the coolant pressure may enter the oil lines through the crack in the cooler.

Removal & Installation To Remove:
WARNING
To avoid being burned, do not remove the radiator cap or surge tank cap while the engine is on or is still hot. The cooling system will release scalding fluid and steam under pressure if radiator cap or surge tank cap is removed while the engine and radiator are still hot.
CAUTION
If the vehicle's coolant is low, drained out, or has repeatedly needed coolant or water added to the system, then the system should be completely flushed.

1. Before servicing the vehicle refer to the precautions at the beginning of this section.
2. Drain the cooling system.
3. Remove or disconnect the following:
   • Inlet hose from the radiator
   • Radiator outlet hose from the radiator
   • Lower fan shroud
   • Surge tank hose
   • Vent inlet hose from the radiator
   • Surge tank hose
   • Engine oil cooler lines from the radiator
   • Transmission oil cooler lines from the radiator Remove the radiator
     
     
   • Radiator bolts
   • Radiator from the vehicle

To Install:

1. Install or connect the following:
   • Radiator to the vehicle
   • Radiator bolts and tighten the bolts, Torque to: 18 ft-lbs (25 Nm)
   • Engine oil cooler lines to the radiator
   • Transmission oil cooler lines to the radiator
   • Radiator vent inlet hose to the radiator
   • Lower fan shroud
   • Outlet hose to the radiator
   • Inlet hose to the radiator
2. Fill the cooling system.
3. Test drive the vehicle to confirm the repairs.

Check for coolant flow at the Purge line,this is a common problem on the Northstar.
There is a small diameter hose coming from near the top of the coolant tank,this is the purge line.
With the engine idling,pull the purge line from the tank,if there is no coolant flow from this small hose,it is blocked and this will cause overheating.If the hose is clear, check for blockage at the nipple on the tank.

I Hope you Find this Helpfull And Please Remember to RATE ME

1. Drain the coolant.
2. Disable the SIR.
3. Move the forwarding discriminating sensor out of the way.
4. Remove the air cleaner assembly.
5. Remove the cooling fans.
6. Disconnect the radiator inlet hose from the radiator.
1. Disconnect the radiator outlet hose from the radiator.
2. Disconnect the engine oil cooler lines from the right radiator end tank.
3. Disconnect the transmission oil cooler lines from the left radiator end tank.
4. Remove the left and the right engine torque struts.
1. Remove the upper radiator support screws.
2. Remove the radiator from the vehicle. Lift the radiator up and out. INSTALLATION PROCEDURE
1. Install the radiator to the vehicle.
2. Install the upper radiator support screws. Tighten the bolts to 6 Nm (53 inch lbs.). NOTICE: Refer to Fastener Notice in Service Precautions.
3. Install the transmission oil cooler lines to the radiator. Tighten the transmission oil cooler line fittings to 27 Nm (20 ft. lbs.).
4. Connect the engine oil cooler lines to the radiator. Tighten the engine oil cooler lines to 18 Nm (13 ft. lbs.).
5. Install the left and the right engine support torque struts.Connect the radiator outlet hose to the radiator.
1. Connect the radiator inlet hose to the radiator.
2. Install the cooling fans.
3. Install the air cleaner assembly.
4. Install the forward discriminating sensor.
5. Enable the SIR.
6. Refill the coolant.
6. Hope this Helps and PLEASE RATE ME