shock proof gear oil

All this discussion is about using the shockproof heavy gearbox oil. Redline has two thinner shockproof oils lightweight and superlightweight oil. What about these? I have used the lightweight version in my /2 BMW with very good results. Shifting really improved. Have not had it in long enough for long term evaluation.

Reading through this thread has both educated and confused me. Last season I swapped out the straight 90 gear oil I've been using forever with this Lucas 75-140 stuff, but I can't find any GL rating for it.



Today I drained the tranny and was relieved to see the stuff come out exceptionally clean, no hint of bronze or other particulates. Anyway, I replaced it with this lighter weight Royal Purple stuff that is labeled GL 4 and 5 safe, so we'll see how it goes

Is this the F12 or F20?? A couple of years back I replaced a radiator in a F20 for a friends like yours with tricycle front end....... what a B****** Of a job it was!!!!

Olympus it's an F30 I went through the radiator hose/fan belt replacement thing last winter PS I done got in trouble talking about the tractor so send me private message if you want to discuss it/them

Some of the conversations about shock proof oils relatively poor searching ability got me concerned cos I’ve been using it for a while.

I tried some Bel Ray Sport transmission fluid, simply as I had it in stock. It improved the shift noticeably in both bikes I tried it in. Which I hypothesise is indicative of better lubricity. It also made the Norton leak out of the clutch cable entry point, something it never did with shock proof, which seems to indicate a better splash and searching property to me.

Bel Ray confirmed it is safe for yellow metals.

It has the added advantage of being suitable for wet clutches, so also takes away the worry of gear oil migrating into the clutch.

The issue with GL5 gear oil being aggressive against bronze & copper has been known for years
GL 5 oil has almost twice the amount of EP additive than GL 4, and it's the high sulphur/phosphorus level in the additive that can be unfavourable & aggressive to bronze.
Like most things in life some folks have used the product for years without issue as it does depend on the spec of oil & bronze used...
Having access to GL5 I had no qualms it putting it in all my transmissions.....and as a result wrecked an airhead gearbox.

olympus said:

The issue with GL5 gear oil being aggressive against bronze & copper has been known for years
GL 5 oil has almost twice the amount of EP additive than GL 4, and it's the high sulphur/phosphorus level in the additive that can be unfavourable & aggressive to bronze.
Like most things in life some folks have used the product for years without issue as it does depend on the spec of oil & bronze used...
Having access to GL5 I had no qualms it putting it in all my transmissions.....and as a result wrecked an airhead gearbox.

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What brand and part # of oil and what exactly did it do?

Not all EP additives are sulphur based, been using EP oils for 40 years and never had a bronze bush eaten by oil.

kommando said:

Not all EP additives are sulphur based, been using EP oils for 40 years and never had a bronze bush eaten by oil.

Click to expand...

I appreciate that, but GL5 oil hasn't been around for 40 years, the problems diddnt occur with GL4 oils..
Problems encountered depend on the oil used and the make up of bronze bushes/ bearing cages used