1200 Gehl Drive
Yankton, SD 57078
Phone: (605) 665-8415
Fax: (605) 665-0810

2200 S. Ohlman Rd
Mitchell, SD 57301-7064
Phone: (800) 843-3324
Fax: (605) 995-3749

2130 3rd Ave NW
West Fargo, ND 58078
Phone: (800) 762-5557
Fax: (701) 282-3039

300 E. Norway Avenue
Mitchell, SD 57301-7064
Phone: (800) 843-3324
Fax: (605) 996-4727

TECHNICAL SERVICE BULLETIN
DATE: 12/28/2021
TSB # TSB202101
RE: TKOLB FRONT IDLER SHAFTS
Model: TKOLBSD & TKOLBHD
Model Years: 2021-2022
Production Build Dates: June 2020 – September 2021
We have identified some failures of the Front Idler Shaft on the latest
design of TKOLBs due to a fatigue issue. Trail King has a new shaft that
will replace shafts built within the production range listed above.
Replacement of the Idler Shaft will take no more than 15 hours to
complete from start to finish. Trail King will supply an upgraded front
idler shaft, bearings as needed, hardware and allow for up to 15 total of
labor for the repair.
Contact Trail King Customer Service for authorization for repair.
Customer Service can be reached at 1-800-843-3324. Ask for Cassidy
Black or Scott Stenseth.
Please see the attached replacement procedure for instructions of the
repair.
Ty Hanten

Director of Quality
Trail King Industries Inc.
Mitchell, SD 57301

Replacing the Front Idler Shaft OLB 2021-2022 Models

Idler Shaft Replacement Procedure – Removal
Please follow the recommended steps provided to safely remove and reinstall the front idler shaft assembly. Trail
King acknowledges that not all shops will follow this procedure based on their own experience and some modification
may be required to complete the same task. At any point if you have questions, please contact Trail King Customer
Service for assistance.
Step 1.
Using Truck or mobile hydraulic pump, rotate belt and chain until the master link/Z-bar is centered in the inspection
door opening similar to picture shown.

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Replacing the Front Idler Shaft OLB 2021-2022 Models

Step 2.
Loosen the belt tension to allow enough play to easily remove the master link/Z-bar. You will need to pull the cotter
pins and slide the master link back in order to remove the bar itself as illustrated by the picture.

Step 3.
Once the bar is removed use the extra master link provided to drive out existing link from the inside as shown leaving it
installed for future rotation. Repeat procedure on Curbside. (Note: Reinstall cotter pins.)

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Replacing the Front Idler Shaft OLB 2021-2022 Models
Step 4.
Rotate belt and chain so that clip is accessible for removal of belt splice rod. (Note: Rotate between landing gear and 5 th
wheel for this step for easy access to remove rod.)

Step 5.
Once the rod is removed rotate the chain till the master link/z bar is centered at the front for removal. After the chain
has been centered the master links may be removed for access to front shaft. (NOTE: Disconnect hydraulic lines from
tractor or pump.)

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Replacing the Front Idler Shaft OLB 2021-2022 Models
Step 6.
Remove the front fenders and front fender mounts.

Step 7.
Remove the 5th Wheel plate

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Replacing the Front Idler Shaft OLB 2021-2022 Models
Step 8. Loosen the chain tension by backing off the tension bolts completely for easy replacement.

Step 9.
Remove the red and blue supply airlines from the back of the front bulkhead/access plate as well as the tap oiler hoses
as shown below.

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Replacing the Front Idler Shaft OLB 2021-2022 Models
Step 10.
Remove front bulkhead plate.
Bolt locations

(Pic 7)

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Replacing the Front Idler Shaft OLB 2021-2022 Models
Step 11.
Remove the master links at the front to split chain for access to idler shaft as shown in picture below.

Step 11.
Remove the 2 set screws and bearing collars from both sides of the trailer. Then remove the 6 bolts from bearing cages
as well.

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Replacing the Front Idler Shaft OLB 2021-2022 Models
Step 12.
Remove the left and right-hand bearing/cage from the Idler shaft. (NOTE: Any paint or build up must be removed prior
to pulling bearing/bearing frame from shaft on both sides.)
(BEARING PULLER MAY BE REQUIRED)

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Replacing the Front Idler Shaft OLB 2021-2022 Models

Idler Shaft Replacement Procedure – Installation
Step 13.
Install the new replacement shaft as shown in the picture. (NOTE: May require an extra set of hands during this step.)

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Replacing the Front Idler Shaft OLB 2021-2022 Models

Step 14.
Install the chain master links and Z bar.

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Replacing the Front Idler Shaft OLB 2021-2022 Models

Step 15.
Coat shaft ends with anti-seize and reinstall bearing/cage assemble on shaft and tighten fasteners accordingly.
Step 16.
Centering shaft on bearings. (NOTE: Make sure the bearings are equal distance with front of trailer before centering
shaft side to side.)

Measure equal distance side to side.

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Replacing the Front Idler Shaft OLB 2021-2022 Models

Step 17.
Installing the bearing collars.
1. Using a 3/8” drill bit - drill into shaft to countersink collar set screws. (NOTE: 2 per collar.)

2.

Install collar and set screws. (NOTE: Use removeable Locktite on set screws before installation.)

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Replacing the Front Idler Shaft OLB 2021-2022 Models

Step 18.
Reinstall airlines, chain oiler lines and front cover.

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Replacing the Front Idler Shaft OLB 2021-2022 Models

Step 19.
Rotate belt and chain slightly for belt connector rod installation as shown below. (NOTE: In the event that you will
operate hydraulics with the tractor, you may need to install the 5 th wheel plate first so you don’t have to move
tractor for future plate installation.)

Step 20:
Installation of the rod may require an additional person to help pinch the clip together in order to feed the connector
rod into place. This can be done at the front of the trailer with the access doors open.

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Replacing the Front Idler Shaft OLB 2021-2022 Models
Step 21: With the rod is completely through the clip cut rod end so that both sides sit on chain tabs equally. Then tack
weld rod ends to chain tabs.

Step 22:
Tension belt and chain to 300 ft lbs. (NOTE: Please reference standard work instruction on proper tension listed on the
front of trailer per decals #800-000-424. If unable to read the decal instructions please refer to the owner’s manual or
contact Trail King Customer Service for assistance.)

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Replacing the Front Idler Shaft OLB 2021-2022 Models
Step 21:
Reinstall the 5th Wheel plate at this time if it hasn’t already been done and tighten fasteners.

Step 22:
Reinstall front fender brackets and fenders.

FINAL STEP: Rotate belt and chain one revolution to make sure everything is good.

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