Powerglide Chassis

TIRE CARE

• What is the most important component of tire care?

TIRE CARE

Maintaining the proper tire inflation pressure is the most important thing you can do to
maximize the life of your tires. An under inflated tire will build up excessive heat that may go
beyond the prescribed limits of endurance of the rubber and the radial cords. Over inflation will
reduce the tire’s foot print on the road, reducing the traction, braking capacity, and handling of
your vehicle. An over inflated tire will also cause a harsh ride, uneven tire wear, and will be more
susceptible to impact damage.
Keep in mind that the pressure rating on the side wall of your tire is the maximum pressure for
that tire. This is not necessarily the correct pressure for the tires when installed on your vehicle.
Maintaining the correct tire pressure for your vehicle’s loaded weight is extremely important and must
be a part of regular vehicle maintenance.

Correct Tire Pressure

To determine the correct air pressure for your tires, load your motor home as you would
normally travel, including water and fuel. Go to a truck scale as found at most major truck stops
and weigh each wheel position independently, with driver and passenger(s) in the vehicle as
described in the Michelin Recreational Vehicle Tire Guide (MWL43146 Rev. 6/07) to
determine the correct air pressure for the weight on each wheel position. Then use the charts in
the guide and adjust the pressure accordingly when the tires are cool or have not been driven for
more than one mile. You may call 1-800-847-3435 for a copy of the Michelin Recreational
Vehicle Tire Guide.
NOTE: Never reduce the air pressure in a hot tire.
REMEMBER: For control of your RV, it is critical that the tire pressure be the same on both
sides of the axle.

Allison Transmission Operation

• Normal driving—best fuel economy

    o Select ―D‖ and ―Mode On‖

• • Performance

    o ―Mode Off‖
    o For mountain driving select lower gears to maintain 2000+ engine RPM

• Hill climbing on hot days

    o Keep RPMs high to cool engine

Allison Transmission Fluid Level Check

Brake System

The rear brakes on the PowerGlide chassis are also used as the parking brakes. This provides
you the holding power of two large drum brakes to prevent your coach from rolling even when
fully loaded on a 20% grade.
A decrease in air pressure will not cause an immediate loss of brakes. If a leak develops in the air
system while driving (at approximately 60 to 65 PSI) you will be alerted via a light on the
instrument panel and an audible alarm. As you apply the brakes, the air supply holding the park
brakes in the released position will gradually be depleted. When fully depleted (approximately 40
PSI to 45 PSI) the rear brakes will set. This allows you sufficient time to pull over to the side of
the road.
NOTE: (The rear brakes have dual chambers—one for the service brakes and one for
the park brake. The service brakes are air applied and spring released. The park brake is
spring applied and air released).
The brake system is equipped with automatic slack adjusters that avoid the need to manually
adjust your brakes. Each time you step on the brake pedal, if adjustment is needed, the adjusters
will take up the slack.

Compressed Air System

The compressed air system is comprised of two air storage tanks. The primary tank stores
and supplies air for the rear brakes, the secondary tank stores and supplies air for the front
brakes.
When air is compressed it becomes hot. As it cools condensed moisture forms in the
system. The air system is equipped with an air dryer to remove most of this moisture. The
dryer has an automatic moisture ejector that releases the trapped moisture back into the
atmosphere. However some moisture will form in the system beyond the dryer, and make
its way into the storage tanks. As moisture collects in the primary and secondary tanks it
displaces the area needed for air storage, thus requiring that the tanks be drained periodically.
The air system is equipped with two air tank drains conveniently located in the left rear
storage compartment. One drain for the primary tank and one for the secondary tank.
These drains should be opened daily for a few seconds to remove any moisture trapped in
the tanks.

Air Dryer

The Tiffin PowerGlide chassis air brake system features a Haldex Purest air dryer which
removes the condensed moisture from compressed air. The air dryer is equipped with a
desiccant cartridge that needs to be changed every 36 months. The dryer is located on the left
hand frame rail (behind the rear axle).
WARNING: Air tanks should be bled of all pressure any time you perform
work on the air system.

Engine Compression Brake

Provides:

• Improved braking power
• Reduces the change of overheating brakes on steep grades
• Works in conjunction with Allison electronic transmission
• Compression brake allows for 3 or 6 cylinder use

All brakes will build up heat when being used due to friction—this is normal. However,
excessive use of the brakes when descending a grade can result in excessive heat and can cause
―brake fade‖ or a loss of braking power, even with disc brakes. The proper way to use your
brakes is to go slowly enough that a fairly light occasional use of the brakes will keep your speed
from increasing.

NOTE: DO NOT maintain continual brake pedal pressure when descending a hill with any
type of brake system.

Rather, down shift the transmission to slow the vehicle and make light, intermittent brake
applications to control downhill speeds. By utilizing the transmission gears and Compression
Brake, continual use of the brakes will not be necessary. When using the transmission’s lower
gears to slow the vehicle on hills, be careful not to exceed the governed speed of your engine. If
engine-governed speed is exceeded, the transmission will shift up to the next range, rapidly
increasing the speed of your vehicle. If you find that you are continually using the brakes to
maintain a safe speed and to keep the RPM within this range, slow the vehicle down even
further and shift the transmission to a lower gear.

CAUTION: DO NOT USE the Compression Brake on wet roads, hazardous, or slippery
conditions. As with any motorized vehicle, practice safety when on the road.

Scheduled Maintenance

Lubrication Points

Maintenance Parts

Primary Fuel Filter / Water Sep W/ WIF sensor
Fleetguard part #             FS1003                                                                     Tiffin part # 31647

Secondary Fuel Filter
Fleetguard part #             FF5636

Engine Oil Filter
Fleetguard part #             LF9009

Engine Air Filter
Parker / Racor #             094973007                                                                 Tiffin part # 30596

Alternator / AC Belt
Gates part #                    K080755                                                                     Tiffin part # 5000139

Fan Drive Belt
Carlisle part #                 RSVX-750-2                                                                Tiffin part # 32306

For assistance with your Tiffin PowerGlide Chassis...

Please contact one of the following
Chassis Specialists at Tiffin Motorhomes, Inc.

256-356-8661

Pre-Trip Inspection

• Check fluid levels & add as necessary
• Check tire inflation pressure
• Look for fluid leaks

Before starting your motor home daily, a few things must be checked. By doing so, you
ensure that a safe trip is in order and lessen your chances of experiencing difficulties while
on the road.

• Check the tires for proper inflation pressure and any damage. Also check the inner duals.
  Refer to the air pressure charts in this manual for proper inflation pressures.
• Look for fluid leaks under the motor home. This can prevent any serious problems from
  occurring later.
• Check the coolant level in the reservoir and add a 50/50 mix of coolant and water if
  necessary. This reservoir can be found on the rear of your vehicle
• Check SCA (supplemental coolant additive) and freeze point every 6 months or
  25,000 miles. Recharge as required.

CAUTION: IF THE WATER TEMP IN YOUR ENGINE IS GREATER THAN 120
DEGREES, DO NOT REMOVE THE RADIATOR CAP! YOU COULD BE
SEVERELY BURNED!

• Approximate COOLING SYSTEM CAPACITIES—does not include the heater core or
  other auxiliary systems added by coach manufacturer:
• Cummins ISL - Side Radiator 56 Qt. or 14 Gallons.
• Check transmission fluid level
• Check engine oil level
• Check for small animals in engine compartment like squirrels, and cats
• Check the power steering fluid reservoir

Pre-Trip Inspection

Check fuel/water separator
ISC / ISL
• Check fuel/water separator and drain any water or contamination that may be present.
After you have completed your inspection, you may now start your engine. Turn the key to the
run position and wait for the wait to start light (in some cases it may read ―Inlet heater‖) to turn
off. You may now start the engine. Never use ether or any other starting fluids to start the
electronic engine. The inlet heater can ignite the fumes and cause an explosion in the air
inlet system. Once you have started the engine, monitor your gauges carefully. Make sure that
the oil pressure rises within 15 seconds. If it does not, shut down the engine and call a repair
facility to determine the cause.

• Check air filter restriction indicator
Brand New Air Cleaner
10‖ to 12‖ of Vacuum
• Engine Air Cleaner Element should be changed when the air inlet restriction indicator reaches
25 inches of vacuum or every two years whichever occurs first.

Instruments & Controls

Message Center
During normal operation the LCD displays the odometer value on the top line and a selected
parameter on the second line.
DRIVE MODE - Display First Line
First line display parameters are odometer and measurement unit selection. Speedometer can be set
to read MPH or km/h by changing this selection. See section on settings and diagnostics.
Speedometer Setup - Units
Speedometer can be set to read MPH or km/h by changing this selection. See section on settings and
diagnostics.

Odometer
The odometer function is always shown with key ON. It can be displayed on the LCD in miles or
kilometers. The odometer reading can be displayed when the ignition switch is OFF by activating
the gauge backlight.
DRIVE MODE - Display Second line
Second line display parameters are selected by pressing the m button for less than 5 seconds.
Pressing the m or t buttons displays a different parameter from the list.

The selected parameter is highlighted with reverse video (sample). The selected parameter is
retained automatically after 5 seconds of inactivity; no further button presses are required. When the
parameter is retained, the reverse video disappears.

Idle Speed Adjustment
When vehicle speed is 0, the cruise on/off switch is in the off position and the cruise control Set or
Resume switch is pressed, the Idle Speed Adjust screen will display on the message center.

Idle speed is adjusted by using the Set & Resume or by using the message center control switches.
The actual engine speed will be displayed as the adjustment is made. Once the Set or Resume
switch has been released, there will be a 10 second delay in removing the Idle Speed Adjust screen
from the LCD. The new idle speed will be retained in the engine control module as the default setting.
Settings and Diagnostic Screens
The Settings and Diagnostic screens can only be accessed when the vehicle speed is equal to 0 mph
and the display is in its normal operating (Drive Mode) screen. Pressing and holding the m button for
longer than 5 seconds enables the Settings and Diagnostics menu.

Once in the Settings and Diagnostics menu, pressing the m or t buttons separately moves the
reverse video highlight (example) up or down through the list, as indicated by the arrows. The
highlighted item is selected when both m and t buttons are pressed at the same time. If no button is
pressed for 5 seconds, the LCD will go back to the standard Drive Screen. The items available in the
menu are:

Set Units
Enables the screen used to select if values are to be displayed in English or Metric units

Contrast
Enables the screen used to set the LCD contrast. Pressing the m (+) button will increase contrast
while pressing the t (-) button will decrease contrast. After 5 seconds of inactivity, the screen reverts
back to the Drive Mode screen. The new contrast setting is written to memory upon returning to the
Drive Mode screen.

Instrument Diagnostics
Enables the screens used to perform diagnostic testing of the instrument system. Navigation through
these menus is the same format as the main menu.

Gauge Test
Each gauge pointer will be driven through three positions, pausing at each position for ½ second. The
LCD shows the position of the pointer as a percentage of full scale. At the end of the test, the gauges
revert back to their original pointer position and the program returns to the Instrument Diagnostics
menu. When available, the warning light internal to the gauge will illuminate steady for the gauge
being tested. Pressing the m button (Exit) will end the test and return to the Instrument Diagnostics
menu. Sample LCD screens:

Lamp Test
Each warning bank light in the instrument panel that is controlled by the gauge network will be 
tested. This test does not test the actual light on the vehicle (vehicle load). Warning lights in 
the secondary gauges are not tested with this feature. They are tested during the Gauge Test 
diagnostic. At the start of the test, all warning bank lights are turned off. Each light is then 
toggled to the “on” state, and then “off”. The LCD displays the name of the light being tested and 
its status. At the end of the test, the lights revert back to their original state (on or off) and 
the program returns to the Instrument Diagnostics menu. Pressing the m button (Exit) will end the 
test and return to the menu. Sample LCD screens:

LCD Test
Displays the ACTIA logo in normal and reverse video three times and then returns to the Instrument 
Diagnostics menu.

Inputs
The module, pin number, and status of each input defined in the system are displayed for this test. 
Pressing the m button exits the test and returns to the menu. Pressing the t button scrolls the 
display to the next 4 inputs. For binary inputs, the value of “high” and “low” refer to the voltage 
level at the connector pin. This information is continuously updated to assist in troubleshooting.

Engine Diagnostics
Enables the screen used to display active Engine fault codes.

Transmission Diagnostics
Enables the screen used to display active Trans fault codes. Screen format is the same as the Engine
Diagnostics Screen.
ABS Diagnostics
Enables the screen used to display active Trans fault codes. Screen format is the same as the Engine
Diagnostics Screen.
Read Parameters
Enables the screen used to display various parameters received by the master gauge. The main use
for these screens is in troubleshooting the system.

Setup Menu
Pressing m and t while turning the ignition on enters the setup menu. Once in the Setup menu,
pressing the m or t buttons separately moves the reverse video highlight (example) up or down
through the list, as indicated by the arrows. The highlighted item is selected when both m and t
buttons are pressed at the same time. If no button is pressed for 5 seconds, the LCD will go back to
the standard Drive Screen.
Self Test
When YES is selected, the start up self test will zero the pointers, sound three tones from the
speaker, sweep the gauge pointers through 50%, 100%, then back to zero, and turn all warning lights
on for 5 seconds. When NO is selected the pointers will zero and all warning lights will be turned on
for 5 seconds. Pressing t toggles between YES and NO, and pressing m exits back to the Setup
Menu screen. The default setting for this is YES.

Cruise Switch Type
This selection changes how the master gauge interprets the three cruise control switch inputs. Upon
entering this screen the present selection will be highlighted in reverse video. The operator is allowed
to select the other method by pressing the t button. Selecting VIP will not be allowed if the binary
input selecting the Rostra Stalk is hardwired low.

Air Supply

The manifold is located in the left front electrical box. The customer quick connect fittings
are located in the left rear of the coach in the compartment labeled “Phone Jacks / TV
Cables.”
CAUTION: Air Tanks should be bled of all pressure before any work is done on the air
system!

Warranty

• Engine
o Cummins ISL 5 Years 100,000 mi

• Transmission
o Allison 3000 MH Series 5 Years 200,000 mi

•  Chassis 3 Years 50,000 mi

•  Drive Train 3 Years 50,000 mi

•  Suspension 3 Years 50,000 mi

*All are completely transferable
 

Allegro Owner’s Club  

The Allegro Owner’s Club is an organization for Allegro motor home owners that provide access to 
rallies and more. Several rallies are organized throughout the year. The rallies are normally a 
package deal which includes your campground fees, entertainment, several meals, transportation to 
and from planned activities, suppliers exhibits, plenty of door prizes, and much more. Service 
technicians from Tiffin Motorhomes, Inc. are also available to do minor repairs to rally 
participants motor homes as well as sales representatives who can answer questions about your motor 
home and other issues. Of course, free time is scheduled into each rally for your personal leisure 
and interests.

If you purchase a new unit, Tiffin Motorhomes pays for your first year of membership. Club members 
are also eligible to purchase insurances at discounted rates as well as other companies that 
provide discounts to our Club members.

Local chapters are also set up throughout the country. These local chapters generally have monthly 
campouts which allow you to meet new friends and share information.

The Allegro Club also publishes a quarterly newsletter, Side Roads, which keeps members informed 
about rallies, caravans, chapter news, safety information, factory news, and much more. Side Roads 
is published in March, June, September, and December.

Allegro Club merchandise is also available at the Allegro Store in Red Bay, AL. You can purchase 
shirts, caps, jackets, and other accessories emblazoned with the Tiffin name brands.

For more information on the Allegro Club or to join, please contact membership coordination at 
256-356-8522 or visit our web site: www.tiffinmotorhomes.com.
 

Suggestions
Please give us your suggestions on what you would like to see
covered in this publication. These should be operation or maintenance items. When you have 
completed your suggestions mail them to Tiffin Motorhomes, 105 2ⁿᵈ Street NW, Red Bay, AL 35582. 
Attention: Gary Harris.