I was thinking since reproductions don't seem to exist that I've found for factory cruise control servos, specifically what the 78 98 had, I was thinking maybe applying a rejuvenator to the rubber diaphram to help it last longer. Does anyone know any good ones, or barring that a rebuild kit in case mine fails at some point later on? Thanks.

 

I had a 93 Buick LeSabre many years ago (2005) with faulty cruise control. I found another servo in the salvage yard and replaced it. It worked for a time but failed again. So, I disassembled the cruise servo. I never found a rebuild kit for it, but I remember cleaning the components and lubing a rubber orifice with the thought that the rubber had failed and caused a vacuum leak. I think I used standard vasoline on the rubber.

I seem to recall that I found a YouTube video many years later that described the suggested GM fix for the cruise control servo. I don't think it was a vacuum leak at all but a faulty actuator rod/ribbon. I thought I posted a link to the video on our website with the thought that 91+ GM H and C bodies were pretty much identical. I'll have to search for the thread.

Here's the thread and it looks like the video link is still good. I suppose nobody has watched it.

https://classicoldsmobile.com/forums...ontrol-140181/

 

Gummi Pflege by nextzett.

 

Jesse - I tried watching it. I'm not sure it would have been any more exciting if a 19 yrs old Raquel Welch had made it.

 

I’m no pro, but check out the YouTube videos on wintergreen oil & water to rejuvenate old rubber. I’m just getting into that level of restoration so I consider myself ignorant.

Thus far what I’ve learned is that wintergreen oil absorbs beautifully and inconsistently into old rubber so results after soaking are unpredictable. I’m in early days, but the oil/water seems useful.

Warmly suggest you learn and run your own experiments.

Cheers
Chris