I see you mention that it helps isolate the cab from frame vibrations. Two things:

1. If the cab mounts are installed correctly there is no metal to metal contact between the cab and frame. Adding extra rubber along that mount should only be necessary if those two surfaces would otherwise be in contact without it.

2. One the most common cause of vibration in the AD trucks can be found in the front motor mount (6-cyl only) assembly. The problem is that the aftermarket rubber mount is shorter that the original to the point where when tightened down the cap and the holding cup touch transmitting engine vibration directly to the frame. Anyone using the aftermarket rubber should cut 1/8" of material from the top of the retaing cup to assure there is no contact.

That being said, I know this modification is very popular but IMHO unnecessary if these two items are done properly. I also expect that my comments will cause some contradictory responses so feel free to post them.

Woody
Your Brother in Bolthood

My 1951 half-ton 'Ol Red

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