Cab bushing replacement

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82BBC20

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Question for anyone that’s dealt with replacing cab bushings, new kit came with these 4 steel plates and based on the hole size they can only go between the new bushings and the cab supports on the floor. What is their purpose and is it mandatory to install them? No instructions with the kit and can’t seem to find anything useful on the web! Thanks John
 

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Smtty58

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Looking at the LMC catalog, they go between the bushing and the cab.
 

82BBC20

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I knew that’s the only place for them to go, my question is why and what do they actually do, what is their purpose?
 

nvrenuf

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I’ve seen them but I’m no engineer. My guess would be to reinforce and spread the load across the cab support, they’re not real thick.
 

ali_c20

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Question for anyone that’s dealt with replacing cab bushings, new kit came with these 4 steel plates and based on the hole size they can only go between the new bushings and the cab supports on the floor. What is their purpose and is it mandatory to install them? No instructions with the kit and can’t seem to find anything useful on the web! Thanks John
They are for aligning the cab/raising the front of the cab a little if needed. My 74 C20 had them in.
 

PrairieDrifter

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Seem like shims.
 

Jims86K20

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They isolate some of the vibration from the chassis to the cab. Over time they can shrink and cause the body lines not to match up. Brothers trucks has a good video on replacement.
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Brban88

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NVRUF is spot on, They are there to distribute the load over a much wider area and to reinforce an area that may be somewhat compromised due to age and conditions.
 

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