I'm posting this because I had the same problem many others have had and still had to "learn the hard way" to get mine resolved. There can never be enough good info on the web about things like this so here goes...
I bought and installed the FRPP Hurst short-throw shifter from a Lincoln/Mercury dealer. It rattled like hell after tightening everything. Which is plain embarrassing. You would thing a company that has been specializing in ONE THING FOR THE LAST 60 YEARS, would be embarrassed too?!! After reading tons of "homegrown" fixes I bought 2 rubber grommets/washers (sold for some other purpose) and sandwiched them in-between the shifter stem and chrome stalk where the 2 bolts go. This quieted the shifter considerably, but did NOT resolve the rattle.
After calling the Hurst customer support line, I was informed that I could take it back to the dealer that sold it to me and ask them to file a warranty claim to send it back to Hurst and that the dealer would likely offer a replacement from their in-stock inventory and to keep trying replacements until I found one that worked. WTF?? Are you kidding me? It's not like you can just install/uninstall in a matter of minutes or anything.... Anyway, apparently, there were some that were manufactured poorly but there is no way to track which ones were, he said. Hurst basically didn't want to take any responsibility for it and suggested I keep trying replacements. After arguing with him about any possible fixes (surely somebody has reported some possible causes/solutions to the Hurst customer service department), he finally suggested that the problem was internal to the stem, where the ball-joint sits and that no amount of external bushing replacement or anything of that sort would resolve the issue. FINALLY, a freakin' honest answer. So with that clue I sprayed some 'white lithium grease' down into the ball/socket area, while shifting through the gears (parked and clutch engaged) to ensure good coating and re-tightened the bolts connecting the stem and stalk and FINALLY...IT'S SILENT IN EVERY GEAR, ON UNEVEN ROAD SURFACES, AT ANY ENGINE RPM. No noise whatsoever! Freakin' hallelujah.
Hurst quality assurance sucks and the company sucks, in general, for making an inferior product that requires the customer to modify it to get it to work to the same standards as the stock shifter. I hope anyone contemplating a Hurst shifter will read this and consider their options. I also hope this will help anybody who is not mechanically-inclined (myself) to fix the problem if they already have a Hurst shifter in their S197 Mustang.
I am going to have to give this a try. Mine rattles mostly in 3rd and 5th. I thought it was because of the differences in heat expansion between the shifter bar and the positive stop screws. After pulling apart the shift boot and assembly several times to make adjustments, it still wasn't eliminated. I will grab my bottle of white lithium when I get home and hopefully this will be the last time taking the shifter apart. Thanks for the info!
The noise probably is the shifter itself unless we're talking about a serious rattle. The rubber gasket/boot from Hurst just isn't as good as stock. A little black silicone around the edges will quiet it down to stock. Mine did the same after I got the louder offroad X pipe.
