Re: 55PackardGuy's '54 Clipper Deluxe

Posted by Owen_Dyneto On 2015/6/22 8:10:49

I TOLD him I thought it said the U-joints should have 140 wt. gear oil. He greased them. I checked the chart again: even though they look like plain grease zerks, they are NOT supposed to be greased, but lubed with 140 wt. using a grease gun.

Packard called for gear oil on the king pins and universal joints for many years, for example on my 34, though Texaco and other independent lube charts of the era indicated chassis grease. Here's the issue as I understand it: There is a small reservoir in the center of the universal joint, if it's filled with gear oil the oil will gradually "spin" out to the cups over a period of time from centrifugal force at a rate allowed by the seepage of the cork seals; this gives lubrication over a lengthened interval. Grease, being immobile, it kind of a "one-shot" lube and is good for as long as the seals retain the grease. So, assuming the seals are reasonably effective I wouldn't be concerned about using grease on the universals but I'd be giving them a shot of grease more often. And DON'T use a high pressure grease gun as it can damage the seals, just use a hand grease gun with modest pressure. And if the seals are not reasonably tight, neither method will be adequate.

The situation with regard to the older style king pins is similar; over time the gear oil, loaded from the top to a reservoir, would continue under the force of gravity to seep down to the lower bearing and provide a longer interval of lubrication which grease, being less mobile, wouldn't do. But using grease is OK IMO as long as you do it often enough and the internal passages remain open. But once you use grease for the first time, the lube passage to the lower bearing is essentially plugged so if you revert back to oil, the oil may no longer be able to pass thru the grease.

So, IMO once you've used grease on either one, if you want to revert to gear oil you really need to either take it apart and clean the grease out, or flush it enough times with gear oil to make sure the passages are clear of grease. For me, I went to grease on my universals and king pins many years ago before I was aware of these nuances so I've stuck with it, just using the grease gun more frequently will no ill effects.

I'm fairly certain the instrument current regulator is mounted to the rear of the instrument cluster, same as prior years - others will correct me if I'm wrong on this.