If I change to Redline 75W90 will it leak ?

Thanks. I'm assuming I'll need to take the car down and test drive it after each adjustment?

Anyone have photos of these forks?

 

The adjustment info provided by Iain is excellent but bear in mind that if you didn't need physical adjustment prior to your oil change you hardly need it now. It's pretty easy to make a passable situation worse so I really would recommend holding fire a little longer before you adjust what does not perhaps require adjustment.

 

Greg, I'm with you on that one as well. I kinda hate dumping the new oil I put it just to find another is no better.

 

The second picture in this post - you can see the three fingers & the fork on the end of the shift shaft

http://www.ferrarichat.com/forum/showpost.php?p=139559396&postcount=7

The 3 fingers are lined up in a straight row but because the selector fork is rotating on the end of the shaft when its acting on the 1-R or 4-5 fork its hitting them at a slight angle. Therefore adjustment/alignment is key to getting a clean change & a small adjustment can make all the difference if the fork is just nicking the adjacent finger to the one you are trying to engage.

When you adjust the thing, you will find that at some points in the range the thing won't go into gear at all, so you can try it at one side of the range, the middle & then the other side & start to get an idea about where it wants to be. You'll be able to get it pretty close, if not dead on, before you drop it on the floor & test drive it.

 

Be careful using GL5 oils in gear boxes meant to use GL4.

Oils are made from base stocks, refined and then mixed with additives to improve them. As a general rule, GL-5's incompatibility is often due to the extreme pressure (EP) wear additives. To give the gear oil its EP rating, it's traditionally been easiest to add a sulfer based friction modifier like MoS2 (molybdenum disulphide) but the broken down sulphur left in the oil (you can smell it) has in the past been responsible for corrosion and pitting of the synchros.

I use Royal Purple Max Gear. It is GL4- GL-5 rated and is non-corrosive to copper, brass, bronze used in the synchros and other various bushings.

http://www.royalpurple.com/product-categories/automotive/#!max-gear

 

On the subject of notchy gearchanges there is a strange statement in the 328 workshop manual which states:

"Each time the gearbox is disassembled, replace the synchro rings if they have over 30,000 KM"
How many times do they expect the gearbox to be disassembled for goodness sake? Also 30,000 KM (18,750 miles) is a stupidly short life expectancy for synchro rings.