Gearboxes.  Which is best, the four or five speed gearbox?  When do they need an easy fix and when a overhaul? How about the other components? 

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Q: Ross D ; I am having a very hard time with the second gear on my 912. I can gear up into second but gearing down from third always elicits a grind even when I have the clutch completely depressed. The strangest thing is that for about a week it worked fine and I was having a grand time driving the car, then all of a sudden when I tried to downshift from third it began to grind again. Any thoughts? I am a relatively new standard driver so any suggestions are appreciated.

A: erik ; Remove the transaxle access cover inside the cabin and take a look at your coupling bushings.  I'll bet that yours are disintegrating and need to be replaced. This same thing happened to me and has now been cured with new bushings. BTW: I bought the entire new coupling with bushings installed. Erik.

Q: christian ; I took a 1967 912 for a test drive today (I am looking to buy my first car). I noticed when moving from 1st to 2nd, it was not so easy, had to kind of move left and right to get into gear without crunching. The owner of a car said this was normal, something to do with a dog leg shift. Can anyone clarify this behaviour. As I say, just not so easy to get into second from 1st. I am only used to driving a new car. Thank you.

A: erik ; Christian, You didn't mention if it was 4- or 5-speed, but I'll assume you mean a 5-speed. Sometimes when the car is first started, sceond gear will "catch" a little because the transaxle is not warmed up enough, but it doesn't crunch unless there is something wrong or you have slammed it in there!
The transaxles on these cars are fairly easy to find...however the ailments that can wreak havoc on the way they shift are numerous.
There isa lot of "monkey motion" going on when you drive and shift. If your transaxle mounts are worn or loose, it will act weird, if your motor mounts are worn or loose, it will act weird...if your coupling bearings are worn or missing, it will shift very badly or almost not at all (don't ask me how I know).
But if the car is in CA, keep looking...they have lots of good rust-free cars out there. If it is a rust free car with "minor" trans issues in say Kansas and the price is right...snap it up! erik.

From: Rick B ; Christian, if it is an early 5-spd, first to second shift should be almost straight up while applying slight pressure to the left, (reverse is locked out). If it is a 4-spd, it should be straight down. These shifters can be somewhat vague, especially if you are on a bumpy road. But there are also plastic and rubber parts that gradually wear out that make shifting more difficult. Under the shifter, there is a plastic cup that is easy to replace; under the access cover at the rear of the shifter tunnel, there is a coupler that is somewhat easy to replace (a good time to replace the dust boots as well), there are two plastic shift arm guides inside the tunnel that are more difficult to replace (but not too bad) and finally the motor mounts, very accessible to change at the fanbelt end of the engine, but not fun at the front of the transmission. Replacing all these parts can make quite a difference!  Rick B

Info on gear oil: click here 

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