Silicon grease is incredible stuff - buy the best quality stuff in bulk, like this:
http://www.ebay.co.uk/itm/310395680423?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2648and also buy a couple of large veterinarian syringes like this:
http://www.ebay.co.uk/itm/151015592667?ssPageName=STRK:MEWAX:VRI&_trksid=p3984.m1423.l2661Take out the plunger and you can pack the grease into the syringe quite easily, and the plunger will squeeze it through very effectively.
The proper quality stuff (not the waterbased 'personal' products

) is completely resistant to diesel, petrol, water, salt water, oil of any sort, detergents, soaps, etc. and will protect electrical connections for decades with one application. It is also entirely safe with rubber, plastic, metal (steel, alloys, etc.) and is unaffected by heat, cold, humidity, etc.
Two warnings:
1. Don't get any on your clothes because NOTHING will wash it out, and don't get it on the seat or grips etc. of your bike because they will stay slippery for a very long time.
2. Don't use it on battery terminals, because battery terminal corrosion isn't neutralised by it at all - better to use a petroleum based grease for that (like Vaseline).
If it does get anywhere you don't want it then you will need to rub it off with dry rags, making sure not to get it anywhere else...
I wouldn't be without it in the garage - use it on bikes, outside door locks (pack the inside of the lock and it will never rust or stick again), cars, generators, lawnmowers, the rubber rings on watch casings, waterproof camera casings, etc.