Factory Peterbilt 379 air suspension between cab and sleeper.

Yes, not too difficult. No drilling at all. Everything fits in the pre-drilled holes .
I do have some pics, I'll try to get them posted this week.

 

Installed by moonlightluwi, on Flickr
Top mounting plate by moonlightluwi, on Flickr
Top mounting plate PN by moonlightluwi, on Flickr
Lower bracket and bags by moonlightluwi, on Flickr
Top plate underside by moonlightluwi, on Flickr
Top of bag by moonlightluwi, on Flickr

 

There seems to be some pressure at the back top of the cab created by the long unsupported span from the cab mounts up front and the sleeper mounts out back. Over time that pressure pushes the cab top forward creating an uneven door jamb to door interface. Starts out with uneven door gaps in the jamb that don't seal well. Then it gets worse until the doors are hard to shut, they don't latch right.

In 2002 I think, Peterbilt started putting these mid-mounted air bags to combat that problem. I just wanted to help any other pre 2002 379 owners who are having this problem to retrofit this system to their truck.

 

Here is how you can tell the problem starting, look at the gap at front top of door compared to rear top.

20170519_124511 by moonlightluwi, on Flickr

 

Nope, these air bags were off of a 2002 379 with a Unibilt, I put them on my 97 also with a Unibilt.

 

Not yet. Was looking into doing it myself but, thinking I would be better off letting Peterbilt handle it.