Help Understanding Bushing Lubrication in Automotive Industry

[YoshiMoshi]

Hello Friends,

So I have seen that polyurethane bushings in the automotive industry are greased every few years or otherwise squeaking will occur. This got me thinking if Rubber bushings in the automotive industry ever need to be greased? I think they are designed to run "dry" and don't need lubrication? I have heard of vehicles that are two to three decades old that have original rubber bushings that have never been greased. But is there any benefit in greasing them?

I've read that silicone can be very beneficial to rubber. Silicone grease can come in either a spray can or grease cartridge form. I've read that petroleum in spray cans is bad for the rubber and can deteriorate it. So silicone grease in a cartridge should be used. Should you inject the grease into the rubber with a needle so it gets absorbed into the bushing, or just put it on the top of the bushing were it is exposed to the elements?

 

[jack action]

This got me thinking if Rubber bushings in the automotive industry ever need to be greased?

No, because:

Rubber does not squeak since the bushing is chemically bonded to the metal shell and sleeve. The torque of suspension movement is soaked up by the bushing internally so the rubber does not move against the metal, and thus, no noise

Should you inject the grease into the rubber with a needle so it gets absorbed into the bushing, or just put it on the top of the bushing were it is exposed to the elements?

You should follow what is recommended by the manufacturer. It is usually a matter of properly greasing them once, during the installation:

Poly bushing design has advanced over the years and even now some manufacturers will guarantee that if their bushings are properly greased upon install later servicing will not be required. Using the right kind of grease for poly bushings is imperative since some grease does not have the same staying power as other options.

 

[Lnewqban]

Please, see:
https://www.gmtrubber.com/advantages-of-using-rubber-bushes/