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Gearbox oils and notchiness.

BuzLightyear
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BuzLightyear Enthusiast

BuzLightyear

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Posted

Somebody recently reported here that gearbox notchiness was improved by switching to Castrol VMX80.

I also have had some degree of notchiness which was really anoying me. I gave the mechanic a drive of my car, which still shifts down quite smoothly, and he was not sure of the cause, that is, whether the synchros were a bit worn or not.I have an R32 which I've only had for a few weeks. When I went to change the oil, I chose VMX80 and decided to give it a Nulon teflon treatment as well, but the filler plug had siezed in the housing, and so I had to give it to the mechanic (Gavin Wood at Autotech here on the Gold Coast). He put the Nulon in, but forgot to put in the VMX80 and instead used his usual fare - a 75/90 of some sort. Result - no improvement.

Today, I decided to drain that mix and just try the VMX80. It has improved the notchiness somewhat, but more importantly because the box now shifts so much easier the notchiness itself now seems a lot less of a problem.... if that makes any sense.

I recall that I had a similar problem with my wife's Corolla. I put 80/90 into it and the box was no better, but switching to a straight 80 as per the manufacturer's recommendations made things somewhat better.

Now I'm going to stay with the 80 weight, but also add the teflon treatment to see if it improves further still.

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https://www.sau.com.au/forums/topic/6463-gearbox-oils-and-notchiness/
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gtrken Grand Master

gtrken

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Posted

Redline Lightweight Shockproof ( blue smurf ) . Exxy but worth it. Improves syncro crunch and shift speed .

Have used in 2xGTRS to good effect and no I don't own the company but wished I did !

Ken

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