So I noticed that when driving my bug - 1971 'S Bug - that the gears would sometimes grind when downshifting into second from third. This wouldn't always happen, and I'm wondering if its something mechanical or just the way I drive the car. Please also note that I am not use to driving these old cars. So I have a few questions:

1. When should I downshift into second gear? If I'm following the markings on the speedo, that is just under 30MPH, which for me seems a bit fast.

2. There is a lot of play in the gear stick, which may be due to the shifter bushing being worn out (I plan on getting this fixed). Could this cause my problems?

3. I can easily shift into second - always - when I am around 15MPH, which is where the gear 1 marker on the speedo is at (same place I shift into second). Would this mean that the second gear syncro is on the way out?

G'day

First thing you need to do is change the front bushing and rear coupler
That will make a huge difference.

Personally I like the CB Rhino coupler.
A bit harsher - but doesnt fall to pieces like a lot of the new ones

https://www.cbperformance.com/ProductDetails.asp?ProductCode=6110 

Gear changing is more about revs than speed
Those speedo markings are more about up shifting than down

Redline is 5,000 rpm (ish)

As a rough guide I would shift up around 3,000 - 3500 and down 2,000 - 2500

That is unless i want to use the engine for braking - then I am happy changing down at higher revs

After you have changed the bush and the coupler, if you still have issues, add some Nulon Smooth Shift G70 additive to the oil in the gearbox. The more you drive the better the shifting from 3rd to 2nd gets. Not a miracle cure, but very effective stuff.
Cheers

Thanks for the fast reply! I'll look into changing the bush and the coupler, but how do I know what rev's I'm at (since all I have is a speedometer).

if you have the stock shifter try to hold up on the stick so it doesn't select reverse
also look at the quick shift kit to reduce your shift distance aka distance between gates.

Yes you are trying to change down unnecessarily soon...
Use the "double de-clutch" method, if/when you need to change down at such a high(er) speed. If still not smooth (eg. may be worse when cold), can change to a full synthetic trans. oil. (eg. 75W-90).