Had transmission service last week - now something is wrong

My son's D3 V8 had some alternative fluid in the transmission when we got it after it had been serviced by the previous owner. We pulled it out and replaced it with Lifeguard 6 as soon as we got it home after I read on the supplied invoices what oil had been used. The car is now up to 230,000km with no transmission issues at all so it doesn't seemed to have been harmed by the alternative oil, luckily. As for yours, the blurb on the web says it is suitable for D3 and D4 ZF 6 speed, but I certainly would not have used it.

The issue with alternative oils is not in the short term but the long term impact on the gearbox.

Is anyone technically minded here? As a complete novice on both oils and transmissions I understood how you would get more long term more wear and tear etc but I’m at a loss to understand he mechanics of how it has an instant effect on the smoothness so if someone can explain it I’d love to learn

curiosity kills

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Originally Posted by Lukeis

Is anyone technically minded here? As a complete novice on both oils and transmissions I understood how you would get more long term more wear and tear etc but I’m at a loss to understand he mechanics of how it has an instant effect on the smoothness so if someone can explain it I’d love to learn

curiosity kills

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Oils have various additives and viscosities. Those both play a part to how the complex interactions of clutch plates occur. An oil that does not conform to the specification may allow slippage between clutch plates, may flow too fast or slow through the valves etc. All this equates to how gears change. Oil flows through valves at a rate and clutches slip at certain rates dictated by the oil. Mess with this and you have the potential for poor performance.
This is no different to the engine which is why we stress to meet the Ford specs as these engines seem to be sensitive.

ZF do have an approved aftermarket lubrication list for their products. Currently there is no aftermarket approved oil as a replacement for LG6,8 or 9
https://aftermarket.zf.com/remotemed...e-ml-11-en.pdf
There are a few oil products out there that claim to meet specs, but nothing that ZF themselves have approved yet

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Originally Posted by shanegtr

ZF do have an approved aftermarket lubrication list for their products. Currently there is no aftermarket approved oil as a replacement for LG6,8 or 9
https://aftermarket.zf.com/remotemed...e-ml-11-en.pdf
There are a few oil products out there that claim to meet specs, but nothing that ZF themselves have approved yet

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Spot on!!!

As one of the primary chemicals of the blend is not available to other blenders I would question if they truly do meet the full specifications!

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Originally Posted by Tombie

Spot on!!!

As one of the primary chemicals of the blend is not available to other blenders I would question if they truly do meet the full specifications!

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Which is that?

Kryptonite

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Originally Posted by PerthDisco

Kryptonite

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[emoji23]

Just to close this one out.

I got the car back today with a gearbox full of ZF Lifeguard 6 and it feels amazing. I didn’t think there was anything wrong with it to start with but now I know how smooth a car can be.

Thanks all all for the input, happy to have a good result.