2016 Ram 3500 Chassis Cab ECU

conditions may be reduced. In all cases, normal operation
will resume once the transmission temperature has risen
to a suitable level.
Transmission Limp Home Mode
Transmission function is monitored electronically for
abnormal conditions. If a condition is detected that could
result in transmission damage, Transmission Limp Home
Mode is activated. In this mode, the transmission remains
in fourth gear (for 66RFE transmission) or third gear (for
AS66RC transmission) regardless of which forward gear
is selected. If an AS66RC equipped truck enters Limp
Home Mode at highway speeds, it will initially engage
fifth gear, until the vehicle slows to a speed where third
gear can be engaged. PARK, REVERSE, and NEUTRAL
will continue to operate. The Malfunction Indicator Light
(MIL) may be illuminated. Limp Home Mode allows the
vehicle to be driven to an authorized dealer for service
without damaging the transmission.In the event of a momentary problem, the transmission
can be reset to regain all forward gears by performing the
following steps:
1. Stop the vehicle.
2. Shift the transmission into PARK.
3. Turn the ignition switch to the OFF position.
4. Wait approximately 10 seconds.
5. Restart the engine.
6. Shift into the desired gear range. If the problem is no
longer detected, the transmission will return to normal
operation.
NOTE: Even if the transmission can be reset, we recom-
mend that you visit your authorized dealer at your
earliest possible convenience. Your authorized dealer has
diagnostic equipment to determine if the problem could
recur.
5
STARTING AND OPERATING 411

front or rear axles has been exceeded but the total load is
within the specified 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.
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.
TRAILER TOWING
In this section you will find safety tips and information
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 recommendations 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
502 STARTING AND OPERATING

CAUTION!
•Do not tow a trailer at all during the first 500 miles
(805 km) the new vehicle is driven. The engine, axle
or other parts could be damaged.
• Then, during the first 500 miles (805 km) that a
trailer is towed, do not drive over 50 mph (80 km/h)
and do not make starts at full throttle. This helps
the engine and other parts of the vehicle wear in at
the heavier loads.
WARNING!
Improper towing can lead to a collision. Follow these
guidelines to make your trailer towing as safe as
possible:
• Make certain that the load is secured in the trailer
and will not shift during travel. When trailering
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WARNING! (Continued)
cargo that is not fully secured, dynamic load shifts
can occur that may be difficult for the driver to
control. You could lose control of your vehicle and
have a collision.
• When hauling cargo or towing a trailer, do not
overload your vehicle or trailer. Overloading can
cause a loss of control, poor performance or dam-
age 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
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510 STARTING AND OPERATING

Recreational Towing — Two-Wheel Drive Models
DO NOT flat tow this vehicle. Damage to the drivetrain
will result.
Recreational towing (for two-wheel drive models) is
allowedONLYif the rear wheels are OFFthe ground.
This may be accomplished using a tow dolly or vehicle
trailer. If using a tow dolly, follow this procedure:
1. Properly secure the dolly to the tow vehicle, following the dolly manufacturer’s instructions.
2. Drive the rear wheels onto the tow dolly.
3. Firmly apply the parking brake. Place automatic trans- mission in PARK, manual transmission in gear (not in
NEUTRAL).
4. Properly secure the rear wheels to the dolly, following the dolly manufacturer’s instructions. 5. Turn the ignition switch to the OFF position and
remove the Key Fob.
6. Install a suitable clamping device, designed for tow- ing, to secure the front wheels in the straight position.
CAUTION!
•Towing with the rear wheels on the ground will
cause severe transmission damage. Damage from
improper towing is not covered under the New
Vehicle Limited Warranty.
• Do not disconnect the driveshaft because fluid may
leak from the transmission, causing damage to
internal parts.
524 STARTING AND OPERATING

WARNING!(Continued)
•Block the wheel diagonally opposite the wheel to
be raised.
• Set the parking brake firmly and set an automatic
transmission in PARK; a manual transmission in
REVERSE.
• Never start or run the engine with the vehicle on a
jack.
• Do not let anyone sit in the vehicle when it is on a
jack.
• Do not get under the vehicle when it is on a jack. If
you need to get under a raised vehicle, take it to a
service center where it can be raised on a lift.
• Only use the jack in the positions indicated and for
lifting this vehicle during a tire change.
• If working on or near a roadway, be extremely
careful of motor traffic.
(Continued)
WARNING! (Continued)
•To assure that spare tires, flat or inflated, are
securely stowed, spares must be stowed with the
valve stem facing the ground.
CAUTION!
Do not attempt to raise the vehicle by jacking on
locations other than those indicated in the Jacking
Instructions for this vehicle.
Jack Warning Label
538 WHAT TO DO IN EMERGENCIES

1. If equipped, remove the spare wheel, jack, and toolsfrom storage.
2. Using the wheel wrench, loosen, but do not remove, the wheel nuts by turning them counterclockwise one
turn while the wheel is still on the ground.
3. When changing the front wheel, assemble the jack drive tube to the jack and connect the drive tube to the
extension tube. Place the jack under the axle as close to
the tire as possible with the drive tubes extending to
the front. Connect the jack tube extension and wheel
wrench.
When changing a rear wheel, assemble the jack drive
tube to the jack and connect the drive tube to the
extension tube. Securely place the jack under the sway
bar bracket (unless both tires are flat on one side, then
place jack under shock bracket) facing forward in vehicle.
Connect the jack tube extension and lug wrench.
Front Jacking Locations
6
WHAT TO DO IN EMERGENCIES 539

Proper towing or lifting equipment is required to prevent
damage to your vehicle. Use only tow bars and other
equipment designed for this purpose, following equip-
ment manufacturer ’s instructions. Use of safety chains is
mandatory. Attach a tow bar or other towing device to
main structural members of the vehicle, not to bumpers
or associated brackets. State and local laws regarding
vehicles under tow must be observed.
If you must use the accessories (wipers, defrosters, etc.)
while being towed, the ignition must be in the ON/RUN
position, not the ACC position.
If the Key Fob is unavailable or the vehicle’s battery is
discharged, refer to “Shift Lever Override” in this section
for instructions on shifting the automatic transmission
out of PARK for towing.CAUTION!
•Do not use sling type equipment when towing.
Vehicle damage may occur.
• When securing the vehicle to a flat bed truck, do
not attach to front or rear suspension components.
Damage to your vehicle may result from improper
towing.
Two-Wheel Drive Models
The manufacturer recommends towing your vehicle with
all four wheels OFFthe ground using a flatbed.
If flatbed equipment is not available, and the transmis-
sion is operable, the vehicle may be towed (with the rear
wheels on the ground) under the following conditions:
• The transmission must be in NEUTRAL.
• The towing speed must not exceed 30 mph (48 km/h).
554 WHAT TO DO IN EMERGENCIES

Brake Fluid Level Check
The fluid level of the master cylinder should be checked
when performing under the hood service or immediately
if the brake system warning lamp indicates system
failure.
The brake master cylinder has a translucent plastic
reservoir. On the outboard side of the reservoir, there is a
“MAX” dot and an “MIN” dot. The fluid level must be
kept within these two dots. Do not add fluid above the
MAX mark because leakage may occur at the cap.
With disc brakes the fluid level can be expected to fall as
the brake linings wear. However, an unexpected drop in
fluid level may be caused by a leak and a system check
should be conducted.
Use only the manufacturer’s recommended brake fluid.
Refer to “Fluids, Lubricants, And Genuine Parts” in
“Maintaining Your Vehicle” for further information.
WARNING!
•Use only manufacturer’s recommended brake fluid.
Refer to “Fluids, Lubricants, And Genuine Parts” in
“Maintaining Your Vehicle” for further information.
Using the wrong type of brake fluid can severely
damage your brake system and/or impair its perfor-
mance. The proper type of brake fluid for your
vehicle is also identified on the original factory
installed hydraulic master cylinder reservoir.
• To avoid contamination from foreign matter or
moisture, use only new brake fluid or fluid that has
been in a tightly closed container. Keep the master
cylinder reservoir cap secured at all times. Brake
fluid in a open container absorbs moisture from the
air resulting in a lower boiling point. This may
cause it to boil unexpectedly during hard or pro-
longed braking, resulting in sudden brake failure.
This could result in a collision.
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590 MAINTAINING YOUR VEHICLE