GMC Motor home Torsion Bar Adjusting Tool
by Gary Zingle
To remove or reinstall the torsion bars on the GMC front wheel drive motor home a tool is required to pre-load the torsion bar prior to removal or installation of the retaining bolt.
If not done properly this procedure could cause damage to parts or people. The following is a tool that I have used successfully for this work. The OTC 927 is a commonly available puller. The rest of the parts are easily made from common materials.
On the GMC Motor home the torsion bar adjusting bolts must only be used hold the torsion bar in adjustment. Adjusting the bolt should not be attempted without first removing the pressure from the torsion bar.
If I built this tool again I would probably use 11/16" threaded rod even though more grinding would be required for clearance on the OTC 927. The lateral loads bend the threaded rods. I would also probably make the threaded rods and the support tubes 1" or 1 ½" shorter to reduce the lateral loads.
Click on photo to see with higher resolution.
The above photos show the tool:
To remove the pressure the arm, rear of torsion bar, contained within the cross member is raised. A reveal has been provided in this arm for this purpose. Significant tension is required to raise this arm.
This puller is based on an OTC 927 puller with the addition of 2 - 5/8" X 11 1/2" threaded rods and the 8 1/2" long cross tube made earlier for the GMC Motorhome spindle puller.
The above photos show the:
- 2 - 1 1/4" X 1 1/4" sq tube Support Tubes 6 1/2" long through which the Threaded Rods pass
- 2 - 5/8" X 11 12" fine thread grade 8 threaded rods ground for puller clearance
- 1 - 1 1/4" X 1 1/4" sq cross tube 8 1/2" long made for the spindle puller
You must evaluate the information presented for you and for your circumstances. If you are without the experience or skills or if the enclosed is not suitable for your use then please do not use. While this assembly has worked well for me I can take no responsibility for your use of this information.