Roger-The only thing the liquid filling does is to dampen the fluatuation of the needle because of the immersion of the needle in the fluid-the lubing of the moving parts of the guage is highly questionable as an asset because more of these gauges are replaced because of leakage of the fluid than other dry gauges are because of worn out needles.

If you guage needle is fluactuating its because your pressure is also--------fix the cause and the needle wobble will go away.