gearbox oil

I think the 2nd synchro takes more abuse because it is used more and because of the slower engagement caused by the hydraulic lock caused by the blind hole in the clutch housing spacer that slows the shift fork rod (especially when the oil is cold and more viscous.) I drilled my blind hole last week.
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Derek,

last time I had my transmission cover off I still wasn't aware of the whole story.
I'm not only glad, that my second gear works without issues. I would love to know, what's going on on my car. Therefore my question for the next time I have my cover removed:
Would I be able to determine, what's going on there? Would one see, whether the relief hole is present or whether the shifter fork has a relief groove?
Or would this require more dismantling?
(what I of course wouldn't do without urgent need)

Best
Martin

 

old Alfa Romeos

For some reason Alfa's 2nd gear syncro holds up about as well as a house of cards.

 

Unless we can figure out how to separate different weight oils in the same gearbox...I'm vindicated!

 

Mike, your response seems to indicate that we're still not seeing eye to eye, so I guess I will go in to more detail. I COMPLETELY AGREE THAT OIL WEIGHT AND TYPE EFFECT TRANSMISSION WEAR AND PERFORMANCE!....and there's more...I know GL4 is the recommended type! If you'll reread my post, you will see my post is not related to that particular concern whatsoever. You're telling me to reread the thread as if I missed something, when in reality you are still misreading my post...just want some clarification...Thanks! Peace, Chaya

 

P.S. Once again you must have misread my other post. I didn't tell anybody to use that oil...the frog told me to use it in my car and I believe him when he tells me it'll work just fine...

 

Not really.

The problem, as we all know, is second gear - but not just for the reasons of cold oil shifting from first to second. The second gear synchro gets the hardest workout of all the gears, because of the relative ratios - the ratio of first to second is greater than second to third etc when upshifting, i.e. The percentage change in rpm due to the change in gear ratios, and on downshifting, the ratio from third down to second is greater than fourth down to third, etc (I hope nobody is trying to shift down from second to first at any speed without double clutch!). So, second gear synchro gets worked harder than any other synchro, so any gear oil shortcomings will show up on second gear shifts (upshift first to second, or downshift third to second) before any other gear shift.

That is why you can have a gear oil problem show up on just second gear - because it will always be the most stressed, and thus the first to show effects of a marginal gear oil while the other gears are just fine. It's the canary in the coal mine, if you like.

 

Gordon, so in other words, it is effected by oil, but can not be "repaired" by oil...that was my point...Vindcated again! Hehehehe!

 

The original discussion centered around the ability to shift through second gear more smoothly (hot or cold) through different oils/viscosities. In that case, yes, oil can be the cure.

Worn or damaged synchro affect can be lessened through oil's but not repaired..

 

Ok...I give up..."Uncle" Hehehe...

 

Redline all the way

 

Which Redline? GL4 or GL5? LOL!

 

Synthetic or natural? LOL!

 

What year is your Ferrari. My '89 Mondial t has Limit Slip, so it says I should use the 75w90 without the NS, but Redline recommends NS. I have the 2nd gear issue. If yours is an '89 or newer &/or has Limited Slip and you're happy w/ NS then that's what I'm going with!

 

This thread was 6 years old before your post! There are multiple different threads discussing the best/most appropriate lubricant - but many of us have moved on from Redline 75W90 to Redline MTL as recommended by Ferrari mechanic Rifledriver.

GL5 hypoid gear oil, like 75W90 and 75W90NS, isn't necessary in a 308 transaxle since there are no extreme pressure hypoid gears present! I was using the Redline 3 litres 75W90/1 litre 75W90NS cocktail when I first got my 308 QV in 2013, but I switched a few years later to straight MTL and the shifting was definitely improved.

Gordon

 

MTL