Technical Service Bulletin (TSB)
Rear Heater Coolant Tube Repair
REFERENCE:

TSB: 07-002-26
GROUP: 07 - Cooling

Date:

April 9, 2026

VEHICLES
AFFECTED:

2018 - **2025** (WD) Dodge Durango
**This bulletin applies to vehicles built on or before June 03, 2025
(MDH 0603XX) equipped with Rear Air Conditioning W/Heater (Sales
Code HBB) and 3.6L V6 24V VVT Engine UPG I W/ESS (Sales Code
ERC).**

REVISION: 23-023-20

MARKET APPLICABILITY:
NA

MEA

EE

IAP

SA

CH

NOTE: **This bulletin applies
to North and South
America, Enlarged
Europe and Middle East
& Africa markets.**
CUSTOMER
SYMPTOM:

Customers may comment on one or more of the following:
● A coolant leak or fluid appearing from under the vehicle.
● Elevated engine coolant temperature and/or indication of overheating.

CAUSE:

**Coolant tube interference**

This bulletin supersedes Technical Service Bulletin (TSB) 23-023-20, date of issue August 25, 2020,
which should be removed from your files. All revisions are highlighted with **asterisks** and include
additional model years, new build date, new sales code, new Market Applicability note, new Cause,
new Repair Procedure note, updated Diagnosis, and updated Repair Procedure steps.
REPAIR SUMMARY:
This bulletin involves inspecting and possibly repairing the rear heater coolant return tube.
CLAIMS DATA:

Labor Operation No:
24-46-17-90

24-46-17-91

Failure Codes

Labor Description
Coolant Return Tube,
Rear Heater - Repair
(2WD Vehicles Only)
(2 - Skilled)
Coolant Return Tube,
Rear Heater - Repair
(4WD Vehicles Only)
(2 - Skilled)
ZZ

Skill Category
1 - Engine Repair and
Performance

Labor Time
2.9 Hrs.

1 - Engine Repair and
Performance

3.0 Hrs.

Service Action

J07 FSAR-TSB-6899

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SPARE PARTS:

Qty.
1 (AR)

Part No.
05069003AA

1 (AR)
2 (AR)

68319146AD
68103040AA

(AR)

68163848AB

Description
Notes
1/2" Coupling, Line Repair –
Kit
Coolant Tube, Outlet
–
Clip, A/C Line Spacer 4–
Way
Mopar Antifreeze/Coolant –
10 Year/150,000 Mile
Formula OAT (Organic
Additive Technology)
meeting the requirements
of Material Standard
MS-90032

DIAGNOSIS:
**If the customer describes any of the symptoms listed above in the customer symptom section, perform the
Repair Procedure.**
SPECIAL TOOLS/EQUIPMENT REQUIRED:

Equipment No.
8456

Description
A/C Line Repair Tool

REPAIR PROCEDURE:
1. **Perform a cooling system pressure test. Refer to the detailed service procedures available in
DealerConnect> Service Library under: Service Info> 07 - Cooling/Diagnosis and Testing.
2. Raise and support the vehicle. Refer to the detailed service procedures available in DealerConnect>
Service Library under: Service Info> 04 - Vehicle Quick Reference/Hoisting/Standard Procedure.
3. Was coolant found to be leaking from the rear heater auxiliary coolant tubes at the engine/bulkhead area?
● YES >>> Proceed to Step 4.
● NO >>> Coolant was not leaking from this area. This Bulletin does not apply. Normal diagnosis should
be performed.

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J07 FSAR-TSB-6899

4. Using a mirror, inspect the rear heater coolant return tube located above the transmission on the left side
of the vehicle Fig. 1 and Fig. 2, for contact on the transmission oil heater tube clamp.

Fig. 1
Location Of Tubes
1 - Rear Heater Coolant Return Tube (Inspect This Tube)
2 - Transmission Oil Heater Tube

Fig. 2
Inspecting For Damage With Mirror
1 - Mirror
2 and 3 - Rear Heater Coolant Return Tube Damage/Leak

5. Are there any signs of a leak, deep wear, or gouging on the aluminum rear heater coolant return tube Fig.
2?
● YES >>> Proceed to Step 6.
● NO >>> Coolant is not leaking from the rear heater coolant tube. This bulletin does not apply. Further
diagnosis should be performed.**
6. Disconnect and isolate the negative battery cable.
7. Partially drain the engine cooling system. Refer to the detailed service procedures available in
DealerConnect> Service Library under: Service Info> 07 - Cooling/Standard Procedure.

J07 FSAR-TSB-6899

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8. Disconnect the heater hose from the underbody heater tube in circled area only Fig. 3.

Fig. 3
Heater Hoses And Tubes
1 - Heater Hoses
2 - Underbody Heater Tube To Disconnect

NOTE: It may be necessary to heat exhaust fasteners to avoid damaging exhaust components.
9. Lower (do not remove) the transmission as necessary to access the rear heater coolant return tube. Refer
to the detailed service procedures available in DealerConnect> Service Library under: Service Info> 21 Transmission and Transfer Case/Automatic - 8HP70/Removal.
10. Partially remove the heat shield from the underbody Fig. 4.

Fig. 4
Cut Line, Spacer And Heat Shield
1 - Four Way A/C Line Spacer Clip
2 - Section Of Tube To Be Cut - Cut Line Location
3 - Heat Shield

11. Remove and DISCARD the two A/C line spacer clips from the lines and tubes Fig. 4.

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J07 FSAR-TSB-6899

12. Disconnect the original rear heater coolant return tube from the upper heater hose.
CAUTION!
Clean/buff both of the cut rear heater coolant return tube ends with a rotational motion around the
tube to avoid longitudinal scratches in the tube. Failure to do so may result in a coolant leak.
13. Using a suitable pipe cutting tool, measure and mark a cut location on the original rear heater coolant
return tube on the vehicle half way on the straight section of the tube Fig. 5.

Fig. 5
Original Coolant Return Tube
1 - Cut Line On Original Coolant Return Tube
2 - Adjacent Tube Wrapped With Tape

14. Wrap the adjacent tube with Tesa tape or equivalent, to prevent the tube splice from making contact with
the tube Fig. 5.
NOTE: Do not replace the entire coolant return tube. The Repair Procedure is to repair the coolant
return tube with a splice.
15. Using a suitable small pipe cutter or equivalent cutting tool and the new coolant tube **P/N 68319146AD**,
mark and cut the line shown in Fig. 6 in the same location as the new coolant return tube cut in Step 13.

Fig. 6
New Coolant Return Tube
1 - Cut Line On New Coolant Return Tube

J07 FSAR-TSB-6899

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16. Using coupling P/N 05069003AA, outlet coolant tube splice P/N 68319146AD and the original rear
heater coolant return tube on the vehicle cut in the previous step, splice the tubes together Fig. 7. Refer
to the detailed service procedures available in DealerConnect> Service Library under: Service Info> 24 Heating and Air Conditioning/Plumbing, Rear/Lines, A/C Underbody/Standard Procedure.

Fig. 7
Tube Splice
17. Connect the spliced rear heater coolant return tube to the upper heater hose on the vehicle.
CAUTION!
Minimum spacing between the transmission oil heater clamp and rear heater coolant return tube
is approximately 25 mm (.98 in.). Use a 22 mm (7/8 in.) socket, or socket of equivalent outside
diameter as a gauge. Failure to space the tubes approximately 25 mm (.98 in). Use a 22 mm (7/8 in.)
may result in wear, or gouging in the aluminum rear heater coolant return tube.
18. Push the transmission oil heater tube forward to increase the clearance between the heater coolant return
tube and transmission oil heater tube clamp Fig. 8.

Fig. 8
Minimum Spacing Socket Location
1 - Transmission Oil Heater Tube
2 - 22 mm (7/8 in.) Socket

19. Install two NEW A/C line spacers on the tubes Fig. 4.
20. Install the heat shield on the underbody Fig. 4.
21. Raise the transmission into place. Refer to the detailed service procedures available in DealerConnect>
Service Library under: Service Info> 21 - Transmission and Transfer Case/Automatic - 8HP70/Installation.
22. Lower the vehicle.

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J07 FSAR-TSB-6899

23. Connect the negative battery cable.
24. Pressure check the coolant system. Refer to the detailed service procedures available in
DealerCONNECT>Service Library under: Service Info> 07 Cooling / Diagnosis and Testing >Leak
Testing>Pressure Tester Method.
25. Is coolant still leaking?
● YES>>> Further diagnosis should be performed.
● NO>>> Proceed to Step 26.
26. Top off the engine coolant. Refer to the detailed service procedures available in DealerConnect> Service
Library under: Service Info>07 - Cooling/Standard Procedure.
27. Start and warm the engine. Check for leaks.
NOTE: ** For SA market only, after applying this TSB, it is not necessary to send DID-I or DID-A.**
POLICY:
Reimbursable within the provisions of the warranty.
This bulletin is supplied as technical information only and is not an authorization for repair. No part of this publication may be reproduced, stored in a retrieval system, or
transmitted, in any form or by any means, electronic, mechanical, photocopying, or otherwise, without written permission of FCA US LLC.