We have been using an air/oil system with linear motion bearings. It uses a light stream of air to move oil along the lines to the bearings. This does 2 things, it provides a positive pressure in the bearings to help stop the ingestion of contamination and also provides a very light constant spray of oil to the bearings preventing load up, where too much lube all at once can actually pump out the seals. If you want more info hit me at deanm@autolube.ca