Preserving suspension bushings.

[jons999]

What is the best way to prevent deterioration and dry rotting or suspension bushings, especially in areas of the country exposed to road salt 4 months a year? I like to spray suspension parts and fasteners with grease every couple oil changes to prevent rust and to make it easier to align the vehicle and replace parts. I would like to spray the bushings with something as well to extend their life but i have heard that petroleum based greases eat the bushings. Would a silicone based spray be better?

 

[Slowzuki]

I have seen silicone based products touting their ability to maintain rubber but I believe it is for sun damage?

I live in the Atlantic provinces of Canada (Ford mentions us in their salt testing as the worst conditions in North America) and bushing life doesn't seem to be affected by the salt.

I drive a 1985 model year vehicle and its body mount bushings are just deteriorating now. Just to note, there are not many cars over 10 years old here. Anything 80's is generally a rustbucket.

 

[FourJawChuck]

Silicone grease is the only thing that will stay put and last, coat your CV boots and other rubber parts with it and they just might last forever.

I use vacuum diaphram grease, works really good on leather to seal out water too.

 

[Chumley]

johns999: Without knowing the specific application and
the type of grease you are using, I can tell you with 100%
confidence that many mineral based lubricants chemically
destroy synthetic rubber isolation bushings/mounts in
short order and should never contact them. Modern
bushings, unless they have grease fittings are usually
designed to operate dry or they are internally lubricated
for life. Does the factory repair manual for your
application suggest any maintenance/lubrication? In
general, if they freeze up, start cracking, squeaking,
grinding, clunking, groaning, or otherwise complaining,
it's time for new ones. Heat and lubricant contamination
usually does the most damage over time.

Lubricants also cause dirt to stick where otherwise, it
wouldn't. Regular washing with clean fresh water under
moderate pressure would be far preferable to any lubricant
to maintain/extend bushing lifespan.

Silicone works as a preservative but it also attracts
dirt which promotes abrasion and corrosion. I've never
used anything on OEM bushings, cv boots, or isolation
mounts and I've found their lifespan acceptable, (8 to
15 years depending on the application) but, I live far
away from the salt belt. I've seen the damage salt does
though. It's ugly stuff.

Hope this helps.

Chumley

 

[matt7]

Rubber will crack and deteriorate from stress as well as environment. The harshest environmental concern is ozone. The earlier post referred to sunlight, it's actually the ozone in the air that causes the rubber to crack. Most OEM manufacturer's of rubber products actually add wax to the rubber compound. The wax is not compatible with the rubber and "blooms" to the surface to protect the rubber from ozone. If you want your bushes to last you have to seal them from the ozone - silicone sounds like a pretty good idea. Heat actually is also very bad for most rubber compounds.