My 2010 Limited has a rattle in the shift linkage which I would say comes from the shaft.
Is there a way to firm up this whole assembly and stop some of the rattling?
Thanks

 

The factory set up sucks. You need to go to a helm joint setup. Cheap and easy, much more stable. If I wasn't mobile I could find the link. Do it and don't look back. Nothing like not being and to shift when merging onto a freeway in traffic...

 

loosen both jam nuts on your shift rod & adjust it tighter to push out the slack.
Hatch.

 

If its the shaft that fits thru the boss on the primary... Remove both outside shift levers , push the shaft back & apply grease to the shaft as best you can. Before you replace both levers get a 1/2" ID dia black nitrite type rubber o-ring, put it on the shaft then put the levers back on. The inside lever will need to be slightly compressed against the o-ring to get the bolt in. The outside lever goes on w/ no issues. This takes out most of the fitment slop & greatly reduces the rattle. Worked on my 07 SG.

 

Also on my 07 RK i removed the shaft from the primary case. Then drilled and tapped for a grease nipple. This will prevent the case and/ or case bushings from wearing out(which is caused mostly by rattling.)

 

I have been told (no personal verification) that the older machines came from the factory with that grease fitting already installed. Others have installed wave washers. Having some slop in the lever/shaft connection on the transmission seems very common also.

 

Yes, this is true, I have grease fittings on my 99 EG, one on the shift lever that goes thru the primary and one on my rear brake lever, I grease them a couple times a month.