Hello together,

last year I installed in my 1993er turbo miata the drivetrain from a crashed anniversary NB.
Since that swap i got oszillating vibrations (depending to rpm) only in the sixth gear. They start at around 2400rpm, but there only very quiet. They get louder to 3200rpm-4100rpm where the reach there maximum. After 4100rpm they get very quiet or disappear completely.

Do you know that problem? In the german forum nobody knows that problem and could give me an advice.
I first thought that have to come from the cardan shaft, but if this would be damaged, it also has to vibrate in gear 1-5?!
I also checked and change the PPF-distance without a change.

Would be very nice, if you can help me.

Thanks so far!
Regards from Germany
Basti

 

The only thing I can think to try it to note the speed range at which it happens and try ot replicate it in 5th gear at the same speeds. There are really only a few things that can cause vibrations- driveshaft and wheels. Luckily, all 1.8L driveshafts are the same and are pretty inexpensive.

 

At the same speed in 5th gear i can not notice any vibrations.
Really only in the 6th gear the problem exists.
Regards!

 

Sounds like a tear down of the trans is what you will have to do.

Have a great day,
Jared

 

Sorry, what do you mean?

Regards

 

I have noticed something similar recently in 5th in my 6 speed, that isn't in any other gear.

Doesn't really bother me. You'll probably have to tear it apart if you're looking for an answer.