tire pressure Ram 2500 2020 Owner's Guide

250STARTING AND OPERATING
Transfer Case Position Indicator Light
The “Transfer Case Position Indicator Light” in
the instrument cluster is used to alert the driver
that the front axle is fully engaged and all four
wheels are driving.
AIR SUSPENSION SYSTEM — IF EQUIPPED
Description
This air suspension system is a rear leveling ride
height system. The main purpose of this system
is to maintain the truck’s rear ride height level.
There are two selectable heights that can be
chosen based on your operating conditions.
The system requires that the ignition be in the
ON/RUN position or the engine running with
zero vehicle speed for all user requested
changes and load leveling.
Rear Leveling Ride Height Switch

Normal Ride Height (NRH) – This is the standard
position of the suspension and is meant for
normal driving. It will automatically adjust to
maintain the rear ride height as conditions
change.
Alternate Trailer Height (ATH) – Lowers the
vehicle approximately 1 inch (25 mm) for a level
truck, to be used as required while trailer
towing. It will automatically adjust to maintain
the rear ride height as conditions change.
Trailer Decoupling/Unloading - The air suspen-
sion system will continue to load level after the
vehicle has been turned off for 10 minutes
without compressor activation. This allows for
easy removal of a trailer and/or load from the
back of the truck by maintaining the ride height.
After 10 minutes you will need to turn the igni -tion to the run position for the air suspension to
re-level due to addition/removal of load in the
vehicle. If the air suspension system is disabled
using the settings menu (Tire Jack Mode, Trans
-
port Mode, Alignment Mode, or Bed Lowering
Mode) the system will remain disabled when
the vehicle is turned off. Reactivating the air
suspension can be accomplished via the
settings menu or driving the vehicle above
5 mph (8 km/h) for Tire Jack Mode, Alignment
Mode, Transport Mode and Bed Lowering
Mode.
NOTE:
Most 3500 models will not lower to Alternate
Trailer Height (ATH) when unloaded.
Refer to “Trailer Towing” in “Starting And
Operating” for further information.
WARNING!
The air suspension system uses a high
pressure volume of air to operate the system.
To avoid personal injury or damage to the
system, see your authorized dealer for
service.

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256STARTING AND OPERATING
firm grip on the steering wheel and maintain a
good driving posture. Avoid sudden accelera -
tions, turns or braking. In most cases there are
no road signs, posted speed limits or signal
lights. Therefore you will need to use your own
good judgment on what is safe and what isn't.
When on a trail you should always be looking
ahead for surface obstacles and changes in
terrain. The key is to plan your future driving
route while remembering what you are currently
driving over.
When To Use Low Range
When driving off-road, shift into 4WD LOW for
additional traction or to improve handling and
control on slippery or difficult terrain. Due to the lower gearing, low range will allow the engine to
operate in a higher power range. This will allow
you to idle over obstacles and down hills, with
improved control and less effort. Also, use 4WD
LOW in rain, ice, snow, mud, and sand to get
heavy loads rolling, improve traction, or when
-
ever 4WD HIGH traction will not do the job.
Driving In Snow, Mud And Sand
There is a drastic reduction in traction when
driving in snow, mud or sand. The vehicle will be
less responsive to steering, acceleration and
braking inputs. Therefore you should accelerate
slowly, leave greater stopping distances and
avoid abrupt vehicle maneuvers. You want to
keep a slow constant steady pace. The key is to
maintain the vehicle's momentum.
Snow – In heavy snow or for additional
control and traction at slower speeds, shift
the transmission to a low gear and shift the
transfer case to 4WD LOW if necessary. Do
not shift to a lower gear than necessary to
maintain headway. Over-revving the engine
can spin the wheels and traction will be lost.
If you start to slow to a stop, try turning your
steering wheel no more than a quarter turn
quickly back and forth, while still applying throttle. This will allow the tires to get a fresh
"bite" and help maintain your momentum.
Mud
– Deep mud creates a great deal of
suction around the tires and is very difficult to
get through. You should use 4WD LOW with a
gear low enough to maintain your momentum
without shifting. If you start to slow to a stop,
try turning your steering wheel no more than
a quarter turn quickly back and forth for addi -
tional traction. Mud holes pose an increased
threat of vehicle damage and getting stuck.
They are normally full of debris from previous
vehicles getting stuck. As a good practice
before entering any mud hole, get out and
determine how deep it is, if there are any
hidden obstacles and if the vehicle can be
safely recovered if stuck.
Sand – Soft sand is very difficult to travel
through with full tire pressure. When crossing
soft sandy spots in a trail, maintain your
vehicle's momentum and do not stop. The
WARNING!
Always wear your seat belt and firmly tie down
cargo. Unsecured cargo can become
projectiles in an off-road situation.
CAUTION!
Never park your vehicle over dry grass or
other combustible materials. The heat from
your vehicle exhaust system could cause a
fire.
CAUTION!
On icy or slippery roads, do not downshift at
high engine RPMs or vehicle speeds because
engine braking may cause skidding and loss
of control.

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STARTING AND OPERATING257
key to driving in soft sand is using the appro -
priate tire pressure, accelerating slowly,
avoiding abrupt maneuvers and maintaining
the vehicle's momentum. If you are going to
be driving on large soft sandy areas or dunes,
reduce your tire pressure to a minimum of
15 psi (103 kPa) to allow for a greater tire
surface area. Reduced tire pressure will dras -
tically improve your traction and handling,
while driving on the soft sand, but you must
return the tires to normal air pressure before
driving on pavement or other hard surfaces.
Be sure you have a way to air the tires back
up prior to reducing the pressure.
Crossing Obstacles (Rocks And Other High
Points)
While driving off road, you will encounter many
types of terrain. These varying types of terrain
bring different types of obstacles. Before
proceeding review the path ahead to determine the correct approach and your ability to safely
recover the vehicle if something goes wrong.
Keeping a firm grip on the steering wheel, bring
the vehicle to a complete stop and then inch the
vehicle forward until it makes contact with the
object. Apply the throttle lightly while holding a
light brake pressure and ease the vehicle up
and over the object.
Using A Spotter
There are many times where it is hard to see the
obstacle or determine the correct path. Deter
-
mining the correct path can be extremely diffi -
cult when you are confronting many obstacles.
In these cases have someone guide you over,
through, or around the obstacle. Have the
person stand a safe distance in front of you
where they can see the obstacle, watch your
tires and undercarriage, and guide you through.
Crossing Large Rocks
When approaching large rocks, choose a path
which ensures you drive over the largest with your tires. This will lift your undercarriage over
the obstacle. The tread of the tire is tougher and
thicker than the side wall and is designed to
take the abuse. Always look ahead and make
every effort to cross the large rocks with your
tires.
Crossing A Ravine, Gully, Ditch, Washout Or
Rut
When crossing a ravine, gully, ditch, washout or
a large rut, the angled approach is the key to
maintaining your vehicle's mobility. Approach
these obstacles at a 45-degree angle and let
each tire go through the obstacle inde
-
pendently. You need to use caution when
crossing large obstacles with steep sides. Do
not attempt to cross any large obstacle with
steep sides at an angle great enough to put the
vehicle at risk of a rollover. If you get caught in
a rut, dig a small trench to the right or left at a
45-degree angle ahead of the front tires. Use
CAUTION!
Reduced tire pressures may cause tire
unseating and total loss of air pressure. To
reduce the risk of tire unseating, while at a
reduced tire pressure, reduce your speed and
avoid sharp turns or abrupt maneuvers.
WARNING!
Crossing obstacles can cause abrupt steering
system loading which could cause you to
loose control of your vehicle.
CAUTION!
Never attempt to straddle a rock that is
large enough to strike your axles or under -
carriage.
Never attempt to drive over a rock which is
large enough to contact the door sills.5

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STARTING AND OPERATING261
around your tires putting you and your vehicle
in jeopardy. There is still a high risk of
personal injury and vehicle damage with
slower water currents in depths greater than
the vehicle's running ground clearance. You
should never attempt to cross flowing water
which is deeper than the vehicle's running
ground clearance. Even the slowest current
can push the heaviest vehicle downstream
out of control if the water is deep enough to
push on the large surface area of the
vehicle's body. Before you proceed deter -
mine the speed of the current, the water's
depth, approach angle, bottom condition and
if there are any obstacles, then cross at an
angle heading slightly upstream using the
low and slow technique.Airing Down For Off-Road Driving
Running lower tire pressure off-road can
improve your ride comfort and vehicle traction.
Reducing the tire air pressure allows the tire to
bulge slightly, improving its surface area for
better flotation and ability to mold or form to the
ground contour. Different terrain, tires, and
vehicles require different tire pressure. Hard
surfaces like rock and heavier vehicles require
higher pressures than softer surfaces such as
sand and lighter vehicles. You will need to
experiment to determine what is right for your
situation. It is easier and faster to let air out
than it is to replace it. Start high and lower it as
required. Remember you must return the tires
to normal air pressure before driving on road or
at highway conditions. Be sure you have a way
to return the tires to their normal on road air
pressure.
Vehicle Recovery
If you drive off-road, you may encounter a situa-
tion where you will need to recover your vehicle.
Vehicle recovery should always be given consid -
eration before attempting a questionable
obstacle. You should never go off-road driving
without the ability to recover your vehicle from a
situation. Having another vehicle with you
usually works best for most situations. The first
thing to do is assess the situation. Why are you
stuck? Are you hung up on something? Would it
be easier to go forward or to go backward? Can
you still move the vehicle? Is there an anchor
point to winch to? Are you alone or do you have
another vehicle to help? Is there high risk of
vehicle damage during the recovery process?
Answering these questions will help you deter -
mine the best method of recovery. If you can still
move the vehicle slightly and the only issue is
slick ground, then rock cycling your vehicle
would be the first choice. If you have ample
room, an additional vehicle and there is low risk
of vehicle impact on the surroundings, then
using a tow strap to the vehicle tow hooks would
be fast and easy. If the vehicle is severely hung
up or in a situation where great care needs to be
taken during the recovery, then nothing can do
the job better than a winch. If you are severely
WARNING!
Never drive through fast moving deep water. It
can push your vehicle downstream, sweeping
it out of control. This could put you and your
passengers at risk of injury or drowning.
CAUTION!
Reduced tire pressure increases the risk of
tire damage and may cause tire unseating
with total loss of air pressure. To reduce the
risk of tire unseating, while at a reduced tire
pressure, drive at slower speeds and avoid
sharp turns or abrupt maneuvers.
5

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318STARTING AND OPERATING
Rim Size
This is the rim size that is appropriate for the tire
size listed.
Inflation Pressure
This is the cold tire inflation pressure for your
vehicle for all loading conditions up to full
GAWR.
Curb Weight
The curb weight of a vehicle is defined as the
total weight of the vehicle with all fluids,
including vehicle fuel, at full capacity condi -
tions, and with no occupants or cargo loaded
into the vehicle. The front and rear curb weight
values are determined by weighing your vehicle
on a commercial scale before any occupants or
cargo are added.
Loading
The actual total weight and the weight of the
front and rear of your vehicle at the ground can
best be determined by weighing it when it is
loaded and ready for operation.
The entire vehicle should first be weighed on a
commercial scale to ensure that the GVWR has
not been exceeded. The weight on the front and
rear of the vehicle should then be determined separately to be sure that the load is properly
distributed over the front and rear axles.
Weighing the vehicle may show that the GAWR
of either the front or rear axle has been
exceeded but the total load is within the speci
-
fied GVWR. If so, weight must be shifted from
front to rear or rear to front as appropriate until
the specified weight limitations are met. Store
the heavier items down low and be sure that the
weight is distributed equally. Stow all loose
items securely before driving.
Improper weight distributions can have an
adverse effect on the way your vehicle steers
and handles and the way the brakes operate.
TRAILER TOWING
In this section you will find safety tips and infor -
mation on limits to the type of towing you can reasonably do with your vehicle. Before towing a
trailer, carefully review this information to tow
your load as efficiently and safely as possible.
To maintain the New Vehicle Limited Warranty
coverage, follow the requirements and recom
-
mendations in this manual concerning vehicles
used for trailer towing.
Common Towing Definitions
The following trailer towing-related definitions
will assist you in understanding the following
information:
Gross Vehicle Weight Rating (GVWR)
The GVWR is the total allowable weight of your
vehicle. This includes driver, passengers, cargo
and tongue weight. The total load must be
limited so that you do not exceed the GVWR.
Refer to “Vehicle Loading/Vehicle Certification
Label” in “Starting And Operating” for further
information.
Gross Trailer Weight (GTW)
The GTW is the weight of the trailer plus the
weight of all cargo, consumables and equip -
ment (permanent or temporary) loaded in or on
the trailer in its "loaded and ready for operation"
condition.
CAUTION!
Do not load your vehicle any heavier than the
GVWR or the maximum front and rear GAWR.
If you do, parts on your vehicle can break, or
it can change the way your vehicle handles.
This could cause you to lose control. Also
overloading can shorten the life of your
vehicle.

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324STARTING AND OPERATING
(Continued)
Towing Requirements — Tires
Do not attempt to tow a trailer while using a
compact spare tire.
Do not drive more than 50 mph (80 km/h) when towing while using a full size spare tire.
Proper tire inflation pressures are essential
to the safe and satisfactory operation of your
vehicle. Refer to “Tires” in “Servicing And
Maintenance” for proper tire inflation proce -
dures.
Check the trailer tires for proper tire inflation
pressures before trailer usage.
Check for signs of tire wear or visible tire
damage before towing a trailer. Refer to
“Tires” in “Servicing And Maintenance” for
the proper inspection procedure.
When replacing tires, refer to “Tires” in
“Servicing And Maintenance” for the proper
tire replacement procedures. Replacing tires
with a higher load carrying capacity will not
increase the vehicle's GVWR and GAWR
limits.
Towing Requirements — Trailer Brakes
Do not interconnect the hydraulic brake
system or vacuum system of your vehicle
with that of the trailer. This could cause inad -
equate braking and possible personal injury.
An electronically actuated trailer brake
controller is required when towing a trailer
with electronically actuated brakes. When
towing a trailer equipped with a hydraulic
surge actuated brake system, an electronic
brake controller is not required.
Trailer brakes are recommended for trailers
over 1,000 lbs (453 kg) and required for
trailers in excess of 2,000 lbs (907 kg).
When hauling cargo or towing a trailer, do
not overload your vehicle or trailer. Over -
loading can cause a loss of control, poor
performance or damage to brakes, axle,
engine, transmission, steering, suspension,
chassis structure or tires.
Safety chains must always be used
between your vehicle and trailer. Always
connect the chains to the hook retainers of
the vehicle hitch. Cross the chains under
the trailer tongue and allow enough slack
for turning corners.
Vehicles with trailers should not be parked
on a grade. When parking, apply the
parking brake on the tow vehicle. Put the
tow vehicle transmission in PARK. For
four-wheel drive vehicles, make sure the
transfer case is not in NEUTRAL. Always,
block or "chock" the trailer wheels.
GCWR must not be exceeded.
WARNING! (Continued)
Total weight must be distributed between
the tow vehicle and the trailer such that the
following four ratings are not exceeded :
GVWR
GTW
GAWR
Tongue weight rating for the trailer
hitch utilized.
WARNING! (Continued)

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336STARTING AND OPERATING
(Continued)
Off-Road Driving Tips
Care should be taken when attempting to climb
steep hills or driving diagonally across a hill or
slope. If natural obstacles force you to travel
diagonally up or down a hill, choose a mild angle
and keep as little side tilt as possible. Keep the
vehicle moving and make turns slowly and
cautiously. If you must back down a hill, back straight down
using REVERSE gear. Never back down in
NEUTRAL or diagonally across the hill.
When driving over sand, mud, and other soft
terrain, shift to low gear and drive steadily.
Apply the accelerator slowly to avoid spinning
the wheels.
Do not reduce the tire pressures for this type of
driving.
After Driving Off-Road
Off-road operation puts more stress on your
vehicle than does most on-road driving. After
going off-road, it is always a good idea to check
for damage. That way you can get any problems
taken care of right away and have your vehicle
ready when you need it.
Completely inspect the underbody of your
vehicle. Check tires, body structure, steering,
suspension, and exhaust system for damage.
Inspect the radiator for mud and debris and
clean as required.
Driving through standing water limits your
vehicle’s braking capabilities, which
increases stopping distances. Therefore,
after driving through standing water, drive
slowly and lightly press on the brake pedal
several times to dry the brakes.
Failure to follow these warnings may result
in injuries that are serious or fatal to you,
your passengers, and others around you.
CAUTION!
Always check the depth of the standing
water before driving through it. Never drive
through standing water that is deeper than
the bottom of the tire rims mounted on the
vehicle.
Determine the condition of the road or the
path that is under water and if there are any
obstacles in the way before driving through
the standing water.
Do not exceed 5 mph (8 km/h) when
driving through standing water. This will
minimize wave effects.
WARNING!
(Continued)
Driving through standing water may cause
damage to your vehicle’s drivetrain compo -
nents. Always inspect your vehicle’s fluids
(i.e., engine oil, transmission, axle, etc.) for
signs of contamination (i.e., fluid that is
milky or foamy in appearance) after driving
through standing water. Do not continue to
operate the vehicle if any fluid appears
contaminated, as this may result in further
damage. Such damage is not covered by
the New Vehicle Limited Warranty.
Getting water inside your vehicle’s engine
can cause it to lock up and stall out, and
cause serious internal damage to the
engine. Such damage is not covered by the
New Vehicle Limited Warranty.
CAUTION! (Continued)

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350IN CASE OF EMERGENCY

Dual Rear Wheel Jack Placement

6. Finish tightening the lug nuts. Push down on the lug wrench while at the end of the handle
for increased leverage. Tighten the lug nuts in
a star pattern until each nut has been tight -
ened twice. For the correct lug nut torque refer
to “Wheel And Tire Torque Specifications” in
“Technical Specifications”. If in doubt about
the correct tightness, have them checked with
a torque wrench by an authorized dealer or
service station. 7. Install the wheel center cap and remove the
wheel blocks. Do not install chrome or
aluminum wheel center caps on the spare
wheel. This may result in cap damage.
8. Lower the jack to its fully closed position. Stow the replaced tire, jack, and tools as
previously described.
NOTE:
The bottle jack will not lower by turning the dial
(thumbwheel) by hand, it may be necessary to
use the jack driver in order to lower the jack.
9. Adjust the tire pressure when possible.
NOTE:
Do not oil wheel studs. For chrome wheels, do
not substitute with chrome plated lug nuts.
To Stow The Flat Or Spare
NOTE:
Have the flat tire repaired or replaced immedi -
ately.

1. Turn the wheel so that the valve stem is facing the ground and toward the rear of
the vehicle for convenience in checking the
spare tire inflation. Slide the wheel retainer
through the center of the wheel.

Reinstalling The Retainer

WARNING!
A loose tire or jack thrown forward in a
collision or hard stop, could endanger the
occupants of the vehicle. Always stow the jack
parts and the spare tire in the places
provided.
WARNING!
A loose tire or jack thrown forward in a
collision or hard stop could endanger the
occupants of the vehicle. Always stow the jack
parts and the spare tire in the places
provided. Have the deflated (flat) tire repaired
or replaced immediately.

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380
SERVICING AND MAINTENANCE
SCHEDULED SERVICING — GAS ENGINE
Your vehicle is equipped with an automatic oil
change indicator system. The oil change indi-
cator system will remind you that it is time to
take your vehicle in for scheduled maintenance.
Based on engine operation conditions, the oil
change indicator message will illuminate. This
means that service is required for your vehicle.
Operating conditions such as frequent
short-trips, trailer tow, extremely hot or cold
ambient temperatures, and E85 fuel usage will
influence when the “Oil Change Required”
message is displayed. Severe Operating Condi-
tions can cause the change oil message to illu -
minate as early as 3,500 miles (5,600 km)
since last reset. Have your vehicle serviced as
soon as possible, within the next 500 miles
(805 km).
Your authorized dealer will reset the oil change
indicator message after completing the sched -
uled oil change.
If a scheduled oil change is performed by
someone other than your authorized dealer, the
message can be reset by referring to the steps described under “Instrument Cluster Display” in
“Getting To Know Your Instrument Panel”.
NOTE:
Under no circumstances should oil change
intervals exceed 8,000 miles (13,000 km),
12 months or 350 hours of engine run time,
whichever comes first. The 350 hours of engine
run or idle time is generally only a concern for
fleet customers.
Severe Duty All Models
NOTE:
Change Engine Oil at 4,000 miles (6,500 km) or
350 hours of engine run time if the vehicle is
operated in a dusty and off road environment or
is operated predominantly at idle, or only very
low engine RPM. This type of vehicle use is
considered Severe Duty.
Once A Month Or Before A Long Trip:
Check engine oil level
Check windshield washer fluid level
Check tire pressure and look for unusual
wear or damage. Rotate tires at the first sign
of irregular wear, even if it occurs before the
oil indicator system turns on.
Check the fluid levels of the coolant reservoir,
brake master cylinder, power steering and
automatic transmission (six-speed only) and
fill as needed
Check function of all interior and exterior
lights
Maintenance Plan — Gasoline Engine
Required Maintenance
Refer to the Maintenance Plan on the following
pages for required maintenance. More frequent
maintenance may be needed in severe condi
-
tions, such as dusty areas and very short trip
driving. In some extreme conditions, additional
maintenance not specified in the maintenance
schedule may be required.

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412SERVICING AND MAINTENANCE
Engine Coolant Checks
Check the engine coolant (antifreeze) protec-
tion every 12 months (before the onset of
freezing weather, where applicable). If the
engine coolant (antifreeze) is dirty or rusty in
appearance, the system should be drained,
flushed and refilled with fresh coolant. Check
the front of the A/C condenser (if equipped) or
radiator for any accumulation of bugs, leaves,
etc. If dirty, clean by gently spraying water from
a garden hose vertically down the face of the
A/C condenser (if equipped) or the back of the
radiator core. Check the engine cooling system hoses for
brittle rubber, cracking, tears, cuts and tight
-
ness of the connection at the coolant recovery
bottle and radiator. Inspect the entire system
for leaks.
DO NOT REMOVE THE COOLANT PRESSURE CAP
WHEN THE COOLING SYSTEM IS HOT.
Cooling System — Drain, Flush And Refill
NOTE:
Some vehicles require special tools to add
coolant properly. Failure to fill these systems
properly could lead to severe internal engine
damage. If any coolant is needed to be added to
the system please contact an authorized
dealer.
If the engine coolant (antifreeze) is dirty or
contains visible sediment, have an authorized
dealer clean and flush with OAT coolant (anti -
freeze) (conforming to MS.90032).
Refer to the “Maintenance Plan” in this section
for the proper maintenance intervals.
Selection Of Coolant
Refer to “Fluids And Lubricants” in “Technical
Specifications” for further information. NOTE:
Mixing of engine coolant (antifreeze) other
than specified Organic Additive Technology
(OAT) engine coolant (antifreeze), may result
in engine damage and may decrease corro
-
sion protection. Organic Additive Technology
(OAT) engine coolant is different and should
not be mixed with Hybrid Organic Additive
Technology (HOAT) engine coolant (anti -
freeze) or any “globally compatible” coolant
(antifreeze). If a non-OAT engine coolant
(antifreeze) is introduced into the cooling
system in an emergency, the cooling system
will need to be drained, flushed, and refilled
with fresh OAT coolant (conforming to
MS.90032), by an authorized dealer as soon
as possible.
Do not use water alone or alcohol-based
engine coolant (antifreeze) products. Do not
use additional rust inhibitors or antirust prod -
ucts, as they may not be compatible with the
radiator engine coolant and may plug the
radiator.
Keep hands, tools, clothing, and jewelry
away from the radiator cooling fan when
the hood is raised. The fan starts automati -
cally and may start at any time, whether the
engine is running or not.
When working near the radiator cooling fan,
disconnect the fan motor lead or turn the
ignition to the OFF mode. The fan is
temperature controlled and can start at any
time the ignition is in the ON mode.
WARNING! (Continued)

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