Shift knob rattle?

[BusBerd]

I have been dealing with a rattle in my stick shift for years.

Years ago I refreshed the shift rod hoping that that would take care of it. It did not. I chalked it up to my inexperience: I must have done something wrong with the refresh. Which still could be true, BUT...

Tonight, I was driving on the highway, and there it was again as always, the stick shift rattling! (really annoying on long trips) I have been trying to narrow down WHEN it rattles at its worst, so I was playing with it a bit (again!) to try to figure where the rattle was coming from. When I grab the stick shift, the rattle goes away. This made sense to me. The vibration is coming up the stick and somewhere the stick is hitting something to make that rattle.
But tonight... I grabbed the stick shift and it went away as usual, but then I grabbed further down the stick to keep the stick from vibrating, but the noise did NOT go away. I repeated this until I realized that when I grabbed the shifter knob, the noise went away, but when I grabbed the stick itself the noise remained!
Then, I unscrewed the shifter knob slightly and the noise diminished.
Then, I unscrewed the shifter knob all the way off and the noise was nearly gone!
I shook the shifter knob in my hand to see if something was loose in there, but no noise.
Since I was driving at night, I had to wait until I got back home to look at the shifter knob closely. It is a stock knob. It is one solid piece as far as I can tell. I cannot see any cracks in it. But it does have a kind of echo chamber underneath where the stick is screwed into it.
I have searched samba for any similar issue, but I have not found any post addressing this.
Rather than immediately just purchase a new shift knob, I am going to try some thread tape around the threads of the stick before I put the knob back on, and maybe not tighten it down too hard.
I don't really understand why or how this rattle is happening just from this knob.
Has anyone else had this issue?????

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"The large print giveth and the small print taketh away."
1977 Westfalia Camper Bus 2.0L Fuel Injected Engine, Manual Transmission

[Whaanga]

I had a similar issue and discovered that both grub screws below the bus on the shift rod were loose. I tightened them up, and the rattle was gone.

Here is a thread that came up recently that might be related:

https://www.thesamba.com/vw/forum/viewtopic.php?t=738533&highlight=

Good Luck - Jeff
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Late 1973 Bay w/a transplanted 914 Engine

[BusBerd]

[Whaanga]

I never removed the shift level knob so I don’t know if this would alter what I was hearing. But, from my experience, if I just touched the shift lever, the rattle would stop. And - if I let up on the gas, the noise would stop. But this noise only occurred at highway speeds.

My hunch is that the noise is not related to the shift lever knob. Rather to something under the bus in the shift rod and its linkage which, is being manifest up through the lever - almost like sympathetic vibrations.
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Late 1973 Bay w/a transplanted 914 Engine

[BusBerd]

[Whaanga]

It seems that the knob might act as a weight that amplifies the movement from below. Perhaps when you removed the knob, the slightly less weight allowed the vibrations to dissipate up through the lever. But - this is only a theory. What if you put some Teflon tape on threads to see if it helps absorb the vibration?

And again, from my experience, check the grub screws and see if they’re tight.
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Late 1973 Bay w/a transplanted 914 Engine

[skills@eurocarsplus]

agree on the grub screws but would like to mention how much grease did you use when you did the bushings? I really pack the hell out of them, same with the front shift rod ball and socket too. a lot of guys seem to just barely lube them up

also if the trans was rebuilt with the steel ball in the selector shaft pivot some complain about some shifter rattle but I never noticed it on mine (probably because I use a ton of grease)

I did a thread about worn out shifter levers...how does the lever look? more specifically the pin slot in the front pipe
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[airschooled]

Jeff, I'm surprised that you missed the resonator design on the underside of the shift knob.

The cavernous space in the plastic mold under some shift knobs acts as an amplifier for any minute rattle. Anything from loose motor mounts, to an out of balance engine, to a bent shift coupler can cause vibration. The knob is only turning existing vibrations into sound.

Once you have ensured that all your shifter parts, bushings, and lubricants are in order, and you promise your shift rod and engine alignment are good, filling the space in the shift knob with play-dough or modeling clay will shut it up for good.

Alternative solutions include a grenedilla wood shift knob to match one's oboe.
Robbie
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[nebe]

Take a tiny glob of clear silicone and smear it around your shifter’s male threads and screw that knob back on and then don’t touch it for at least 24 hours. Your rattle will be gone and you will still be able to easy unscrew the knob I’d you have to. Consider painting your shifter lever first because paint won’t want to stick to silicone. If that’s a concern, use polysulfide sealant. Paint will stick to that. Both will stop that rattle

[BusBerd]

[Whaanga]

[Wildthings]

Any thought on what just taping a weight to the shift lever would do? or alternately assuming the shift lever is solid steel, maybe finding a hollow one in the wrecking yard and welding it onto the stub of the OEM VW one?

[SGKent]

it is a one year old post.

One source of rattles in the shifter are the steel doughnut that some folks use in the nosecone. The rattle transmits all the way forward. That is probably why VW used a fiberglass reinforced plastic ball. They are still out there if you can find them. You can see the threads of fiberglass or something like it in them.
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“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin