There is an issue, you are right. There is a property of oils called
lubricity. For some types of cars and some types of synchros, some
synthetics have too much lubricity. They are too "slippery" and they
prevent the synchros from gripping well enough to do their job. The
folks at Redline like to think they have solved the problem, but they
can't be sure it will work in all cars. Old Alfas, for example, could
have either of 2 different types of synchros with 2 very different
lubrication requirements. I was running the 50/50 mix of MT90 and
conventional oil in my FJ transaxle, and shifting was better than
conventional alone. I did not try the MT90 alone. The full synthetic I
am on now appears to be better still. My transaxle is an oddball, so it
may not apply to others. This is a case where testimonials may have
SOME value. If you can find somebody with a car EXACTLY like yours, and
he has the race miles to prove his solution works, try it.
The problem with conventional oils is that under the stresses of racing,
the film strength isn't enough to prevent metal to metal contact. This
knowledge could have saved me about $2k in tranny work. ;=(
> Simon,This is an interesting thread & I do have a specific case.We had been
> using Redline in the TR6 gearbox & everything seemed fine.However,it
> seemed to be grinding a lot on gear changes.I dismantled the box & found
> most of the shift dogs on the close ratio gears had a good deal of wear.
> i checked each syncro with the factory tool for checking the syncro balls
> & shift preload ,all were within spec.Desperate for a solution I called a
> resource
> I know who stated it appeared to him that I might be cheating the syncro
> rings
> with a lubricant too slick.I tried a more conventional lubricant & problem
> solved.
>
> KEN G
>
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