Revisions to this document are noted by a
stripe in the left-hand margin

SUBJECT:

IS 297, Rev. B
P/N (None)
January 12, 2026
Page 1 of 8

Oil Sampling Procedure and Fluid Analysis

OIL SAMPLING PROCEDURE
Installation of Quick Draw Valve
The most uniform samples are obtained when the transmission is in Neutral, idle speed, and at operating
temperature. To collect a sample under these conditions, POLARIS Laboraties™ offers a sampling valve that can
be installed in an oil gallery with constantly circulating fluid. Contact POLARIS Laboratories to determine which
Push Button Sampling Valve is most appropriate for the specific transmission series.
POLARIS Laboratories
7451 Winton Drive
PO Box 68983
Indianapolis, IN 46268
TOLL FREE: (877) 808-3750
custserv@polarislabs.com
The Push Button Sampling Valve is shown in Figure 1. For on-highway transmissions, refer to Figure 2, Figure 3,
or Figure 4 for recommended placement of the Push Button Sampling Valve.
Refer to Table 1 for Push Button Sampling Valve torque values. An optional remote provision for the Push Button
Sampling Valve is depicted in Figure 5.
NOTE: It may be necessary to tap into the cooler line fittings to provide accessibility.
Table 1 Push Button Sampling Valve Torque Values
Model
1000 Series™, 2000 Series™, 3000 Series™, and 4000 Series™

Torque Values
10-13 N·m (7-10 lb ft)

5000 Series™, 6000 Series™, 8000 Series™, 9000 Series™, and
FracTran®
NPT

5.4-6.8 N·m (4-5 lb ft)

Straight-Thread

10-13 N·m (7-10 lb ft)

CK / IS8372EN

xi69532

Copyright © 2026 Allison Transmission, Inc. All Rights Reserved.

IS 297, Rev. B
(None)
January 12, 2026
Page 2 of 8
CAUTION: Vehicle operating environment must be considered if permanent installation of Push Button
Sampling Valve or remote oil sample hose is desired. Vehicles that operate off-road or have low ground
clearance pose a greater risk of road/debris impact to the Push Button Sampling Valve and subsequent
transmission damage.
Fluid Sampling
Proper fluid sampling consists of the following procedure:
•
•
•

The first sample data point must be from an unused, new fluid sample to establish initial levels for which
subsequent used oil samples will be compared.
Second sample data points of used oil samples should be taken per recommendations in Table 4.
Subsequent sample data points of used oil samples should be taken per recommendations in Table 5.
Subsequent draw of used oil samples will continue until the fluid exceeds any of the limits contained in
Table 2 and Table 3.

Once a fluid/filter change is performed, the next sample data point should occur per the recommendations in
Table 4. Subsequent sample data points should again be taken per the recommendations in Table 5 until the fluid
exceeds any of the limits contained in Table 2 and Table 3.
Extraction of Fluid Sample
To obtain a representative fluid sample, the following conditions must exist at the time the fluid sample is taken:
1.
2.
3.

Transmission sump temperature above 60ºC (140°F) (If transmission temperature is not available, engine
must be at operating temperature).
Engine at idle, transmission in Neutral.
Vehicle wheels chocked and vehicle brakes applied.

Before attaching collection bottle, push the button on end of Push Button Sampling Valve to allow a minimum
of 90 mL (3 fl oz) to purge into a container. This removes prior oil/debris trapped in Push Button Sampling
Valve and/or remote oil sample hose. Once Push Button Sampling Valve and/or remote oil sample hose has
been purged, position collection bottle under the Push Button Sampling Valve output port and fill collection bottle
approximately 3/4 full or to the FILL LINE marked on the sample collection bottle.
Submission of Oil Sample:
To register the sample, go to (https://www.eoilreports.com/login) or download the Horizon Fluid Analysis Results
App from Google Play or Apple App Store on a mobile device and login to HORIZON. If you do not have a login,
follow the steps on the login screen to create a new account. Follow the steps for submitting by selecting your
account number, component ID and enter all relevant information into the form. Fill out the sample label, attach
label to the bottle, package carefully using materials supplied in the kit and send it immediately.
If there is no access to Internet or a device to submit on-line, follow the steps below to submit and enter the
information manually.
Fill out the label completely with the transmission serial number, hour meter/mileage reading, sample date, and
hours/miles accumulated on the oil. Indicate whether or not the oil was changed after the sample was taken.
Attach the label to the bottle, package carefully using materials supplied by the lab and send it immediately.
Presence of glycol contamination is analyzed. Cost of oil analysis is included in the cost of the oil analysis kit P/N
29537805.

Copyright © 2026 Allison Transmission, Inc. All Rights Reserved.

IS 297, Rev. B
(None)
January 12, 2026
Page 3 of 8

FLUID ANALYSIS
Transmission protection and fluid change intervals can be optimized by monitoring fluid viscosity and oxidation.
Fluid degradation is monitored by testing for viscosity and total acid number (TAN). Fluid oxidation limits are
shown in Table 2.
Table 2 Fluid Oxidation Limits
Condition

Limit

Viscosity

+/- 25% Change From New Fluid

Total Acid Number

+3.0 Change From New Fluid

Since limits are referenced from an unused oil sample, when beginning fluid analysis or repurchasing bulk oil
stock, i.e. 55 gallon drum and larger, collect a new, unused oil sample and submit for analysis. Viscosity and TAN
values measured from unused sample create the baseline that future used oil sample will be measured against.
Monitoring Contaminant Levels:
The presence of contaminants in the transmission fluid is detrimental and indicates a fluid change is necessary.
Contaminant limits are shown in Table 3.
Table 3 Contaminant Limits
Contaminant

Limit

Water

0.2% Maximum

Glycol

No Trace Allowed

Alien Fluids*

If Detected, Change Transmission Fluid

* Any fluid not meeting Allison approval. Refer to www.allisontransmission.com/aftermarket-and-channel/parts-and-service/allison-approvedfluids or the latest revision of Service Information Letter (SIL) 10-TR-99 for a listing of approved fluids.

Monitoring Wear:
Absolute maximum values are not applied to wear metals of an automatic transmission due to the many variables
present that affect concentration limits. Wear metal analysis results must be evaluated using a trendline approach.
A trendline approach plots the concentration level of each wear metal over a period of time. A line of best fit
drawn through the plotted points is considered a trendline. A minimum of 4 data points for each wear metal is
required to establish a trendline.
Concern should only occur when significant deviations in the established trendline are present. While trendline
analysis on wear metals can prove informative and useful, a transmission removal decision should not be based
solely upon the analysis. The results should be used in conjunction with other inspection procedures such as a
functional check, road test, oil sump/internal filter inspection, or elevated particle counts. A removal based solely
on wear metal analysis may result in an unnecessary teardown. Transmission removal should occur only if the
additional investigation warrants it.
If there is ever any doubt on the significance of any fluid analysis reports, or a need to react to a condition,
assistance should be sought through a servicing outlet or Allison Transmission regional office.

Copyright © 2026 Allison Transmission, Inc. All Rights Reserved.

IS 297, Rev. B
(None)
January 12, 2026
Page 4 of 8
Table 4 Recommended Initial Fluid Sample Draw
TES 295®/TES 668®/TES 353™ Approved
Fluid

Model

Vocation

1000 and
2000 Series

Severe

24,000 km (15,000 miles)

600 hours

40,000 km (25,000 miles)

1000 hours

General

40,000 km (25,000 miles)

1000 hours

80,000 km (50,000 miles)

2000 hours

Severe*

8000 km (5000 miles)

200 hours

(40,000 km (25,000 miles))

1000 hours

General**

24,000 km (15,000 miles)

600 hours

80,000 km (50,000 miles)

2000 hours

3000 and
4000 Series

TES 389®/TES 439™ Approved Fluid

5000, 6000,
8000, and
9000 Series
and FracTran

250 hours

250 hours

* Severe Vocation: All Retarders, On/Off Highway, Refuse, Transit, and Intercity Coach with duty cycle greater than one (1) stop per mile.
** General Vocation: Intercity Coach with duty cycle less than or equal to one (1) stop per mile and all other vocations.

Table 5 Recommended Subsequent Fluid Sample Rates
Model

TES 389/TES 439 Approved Fluid

TES 295/TES 668/TES 353 Approved
Fluid

1000 and 2000 Series

250 hours

500 hours

3000 and 4000 Series

8000 km (5000 miles)

16,000 km (10,000 miles)

5000, 6000, 8000, and 9000 Series and
FracTran

250 hours

250 hours

NOTE: Fluid sample frequency may need to be modified due to analysis results. For example, if analysis
indicates fluid viscosity has changed by 25 percent, customer should sample at a greater frequency
than recommended in Table 5. Local conditions, severity of operation or duty cycle may require more or
less frequent fluid sample intervals that differ from the published recommended fluid sample intervals of
Allison Transmission.

Copyright © 2026 Allison Transmission, Inc. All Rights Reserved.

IS 297, Rev. B
(None)
January 12, 2026
Page 5 of 8

7001219

Figure 1. Push Button Sampling Valve
MAIN-PRESSURE TAPS
NOTE: Inch Series Threads

7001220

Figure 2. 1000 and 2000 Series

Copyright © 2026 Allison Transmission, Inc. All Rights Reserved.

IS 297, Rev. B
(None)
January 12, 2026
Page 6 of 8

3000 SERIES™

4000 SERIES™

MAIN-PRESSURE TAP
NOTE: Inch Series Threads

MAIN-PRESSURE TAP

NOTE: Inch Series Threads

MAIN-PRESSURE TAP
NOTE: Inch Series Threads

Figure 3. 3000 and 4000 Series

Copyright © 2026 Allison Transmission, Inc. All Rights Reserved.

7001221

IS 297, Rev. B
(None)
January 12, 2026
Page 7 of 8
MAIN-PRESSURE TAPS
NOTE: Inch Series Threads

7001222

Figure 4. 5000, 6000, 8000, and 9000 Series

Copyright © 2026 Allison Transmission, Inc. All Rights Reserved.

IS 297, Rev. B
(None)
January 12, 2026
Page 8 of 8
919-4 HOSE
WITH
10691N-4-4 FITTING

4 GTX

To
Transmission
4 C5OX
1.19 in.
0.125 in.

0.563 in.
0.438 in. - 20

1.52 in.
1.00 in.

0.89 in.

0.563 in.

0.64 in.

0.563 in.

0.79 in.

0.438 in.
- 20

0.76 in.

0.438 in.
- 20
0.125 in. - 27

0.438 in. - 20

4 GTX

10691N-4-4
FITTING

4 C5OX
(1000/2000 SERIES,
3000/4000 SERIES,
5/6/8/9000 SERIES)
7001223

Figure 5. Optional Remote Provision
•
•
•
•

•
•
•

Recommended maximum length of hose is 3 meters (10 feet).
Hose must not contact or have potential to contact sharp or abrading surfaces.
Hose must be routed carefully to avoid sharp bends, kinking, pinching, cutting, or rubbing.
The hose must not be under tension between fixed points. This is especially relevant in view of the
movement of the powerpack within the frame. "Tension" is considered to be any strain greater than the
hose itself.
Hose must be a minimum of 203 mm (8 in.) from radiant heat sources. Heat sources are defined as engine
exhaust systems and manifolds.
Hose should be secured every 400 mm (16 in.). Clamps must be properly sized to the OD of the hose to
avoid crushing or deforming the hose.
Torque hydraulic fittings to manufacturer’s specifications.

Refer to Figure 2, Figure 3, or Figure 4 for placement of fitting.
Refer to Table 1 for adapter to transmission torque values.

Copyright © 2026 Allison Transmission, Inc. All Rights Reserved.