I think I will order a new yoke just to be sure . There is enough play in the yoke that I can see it . I will also pack the yoke with moly .. thanks AJ
I've suffered from a similar vibration for a long time. Be careful using moly on the splines/inside the yoke. That grease can wash out into your transmission and lead to problems. ATF is a very efficient detergent type liquid.
My trans yoke is a new forged unit from Mark Williams. The outside diameter of the barrel is 1.505". Even with a brand new bronze bushing installed, it would wobble back and forth .030" at the u-joint, which I can feel is way to sloppy for new parts and the likely source of vibration /rumble when the driveline is between acceleration and deceleration or coasting in other words.
After years of suffering from this, I installed a teflon coated bushing from a GM 4L60 extension housing. It's a steel backed bushing with a single linear split and a white teflon or delrin inner surface. Ford C4's & C6's also have the same size bushings, but are harder to find the teflon/delrin coated bushings for.
I was about to have my yoke hard chromed to reduce the clearance, when the shop manager squeezed the GM bushing with his fingers onto the barrel of my yoke to simulate what it would fit like installed. There was virtually no detectable play, but it spun and slide beautifully on the yoke's barrel.
I installed the bushing yesterday. It slide in just like the stock one does. I put my yoke back on my driveshaft and installed it. It fit, slide and turned beautifully with absolutely no more side to side play. Problem solved.
I called my friend to tell him about my find, and he is going to install one on his car. He is a machinist and actually made an oversized bushing which still had a touch of play.
I now believe this is a solution for a problem that has plagued many of us Mopar guys for years. The new bushing and seal was less than $20 and it took a matter of minutes to replace in the car with a simple tool designed for the job.
Often times a man's life in these parts depends upon a mere scrap of information.