Eaton AT-1202 User manual

Service Manual
Eaton Fuller Heavy-Duty
Transmissions
TRSM0996 EN-US
April 2019
AT-1202 Models

Specifications
1
General Information
Warnings and Precautions
Before starting a vehicle always be seated in the driver’s seat, place the transmission in neutral, set the parking brakes and
disengage the clutch.
Before working on a vehicle place the transmission in neutral, set the parking brakes and block the wheels.
Before towing the vehicle place the transmission in neutral, and lift the rear wheels off the ground, remove the axle shafts,
or disconnect the driveline to avoid damage to the transmission during towing.
The description and specifications contained in this service publication are current at the time of printing.
Eaton Corporation reserves the right to discontinue or modify its models and/or procedures and to change specifications at any
time without notice.
Any reference to brand name in this publication is made as an example of the types of tools and materials recommended for use
and should not be considered an endorsement. Equivalents may be used.
This symbol is used throughout this manual to call attention to procedures where carelessness or failure to follow
specific instructions may result in personal injury and/or component damage.
Departure from the instructions, choice of tools, materials and recommended parts mentioned in this publication may jeopardize
the personal safety of the service technician or vehicle operator.
Warning: Failure to follow indicated procedures creates a high risk of personal injury to the servicing technician.
Caution: Failure to follow indicated procedures may cause component damage or malfunction.
Note: Additional service information not covered in the service procedures.
Tip: Helpful removal and installation procedures to aid in the service of this unit.
Always use genuine Eaton replacement parts.

Introduction
2
Description
The AT-1202 model is a two-speed, twin countershaft auxiliary transmission designed primarily for use with heavy-duty transmis-
sions.
This auxiliary transmission contains two sets of gears, thus giving the reduction (low) ratio when power is delivered through these
two sets of gears. The other speed is obtained by direct (high) drive through the auxiliary. A single shift bar in the right side of the
case controls speed changes.

Specifications
3
General Information
Shift Positions and Specifications
Specifications
Gear Ratios
Mountings
Front bearing cover machined for trunnion mounting.
Four 5/8" diameter mounting studs, two on each side of case.
Gear Ratios
Direct 1.00
Reduction 2.036
Power Take-OFF
Bottom SAE Standard 6-bolt, 30 tooth, 5P gear on left coun-
tershaft turning at .993 input shaft speed.
Top SAE Standard 8-bolt, 30 tooth, 5P gear on right coun-
tershaft turning at .993 input shaft speed.
Weight 330 pounds
Oil Capacity 12 pints
Installation length 16-3/16 inches
Shift Positions
Nuetral
Direct
Reduction

Lubrication
4
Lubrication Specifications
Note: For a list of Eaton Approved Synthetic Lubricants, see TCMT-0021 the list of approved lubricants and TCMT-0021 the list of
lube intervals, or call 1-800-826-HELP (4357). Recommended lubricants for the 2-A-92 are currently the E500 and the E250,
which list a mileage, a year, and a hour change interval.
Note: The use of lubricants not meeting these requirements will affect warranty coverage.
Note: Additives and friction modifiers must not be introduced.
Note: Never mix engine oils and gear oils in the same transmission.
Buy from a reputable dealer
For a complete list of approved and reputable dealers, write to: Eaton Corporation, Worldwide Marketing Services, P.O. Box 4013,
Kalamazoo, MI 49003
Transmission Operating Angles
If the transmission operating angle is more than 12 degrees, improper lubrication will occur. The operating angle is the transmis-
sion mounting angle in the chassis plus the percent of upgrade (expressed in degrees). For operating angles over 12 degrees, the
transmission must be equipped with an oil pump or cooler kit to insure proper lubrication.
Mixing of Oil Types
CAUTION: Never mix engine oils & gear oils in the same transmission.
Engine oils and gear oils may not be compatible; mixing can cause breakdown of the lubricant and affect component performance.
When switching between types of lubricants, all areas of each affected component must be thoroughly flushed.
Operating Temperature
Oil Coolers
Kit K-1702 includes the pump, cooler and accesories to convert the AT-1202.