Ford Syn Tranny Fluid

[Funracer]

In addition to the Z I have owned 5 Miatas over the last 8 years.

I read on a Miata forum lots of guys are putting Ford Full Synthetic Manual Transmission
Fluid in the trannys with good reports. I purchased some at the local Ford dealer
and put it in my 1997 MX5.

It is by far the best shifting fluid I have tried in the Miatas. Like Buttah, and it
gets better the longer you use it.

Any Z guys tried this fluid in the ZF? Next time I do any work under the car
I am willing to give it a try unless someone has heard bad stories about it.

[gbrtng]

Way back in the distance past, some tried Mobil 1 10W30 synthetic in ZFs. Turns out it was too slippery and second and third gear synchros began failing - some were repaired and replaced under warranty, but others were not so lucky. I say try it at your own risk.
And report back in a few thousand miles - you may have found the final solution ...

[Funracer]

some tried Mobil 1 10W30 synthetic in ZFs.

My guess is fluid actually made for manual transmissions
will work better than engine oil.

[mike100]

Ford part: XT-M5-QS

The use of that has crossed my mind. It is thicker than synchromesh lube- maybe motor oil equivalent viscosity to a 10w-40 or a 20w-40. My MT-82 trans in my '12 mustang has that and it doesn't flow as well as Amsoil synchromesh in the morning.

I actually lost a main bearing in my mustang running the Amsoil, but it was the Chinese QC and assembly that i blame as the trans guy said he didn't think it was lubrication related....but still kind of makes you wonder. It did shift super with the thinner oil though. but I bet the ford synth trans oil would work fine as it is made for modern synchros and the mustang transmission is a copy of a euro Getrag design.

[Funracer]

Motorcraft® Full Synthetic Manual Transmission Fluid is a premium-quality SAE 75W-90 gear oil recommended by Ford Motor Company meeting warranty requirements. It is particularly recommended for 1995-2011 MTX-75 and IB5 transmissions, and is also recommended for older transmissions including rear wheel drive that recommend GL-3 and GL-4 type gear oils

Motorcraft® Full Synthetic Manual Transmission Fluid is manufactured with synthetic base oils and performance additives providing improved gear shifting at all ambient temperatures. Its wear protection extends the life of synchronizers and bearings

Due to its excellent thermal, oxidative and shear stability, this fluid meets Ford’s fill-for-life requirements. Reduced friction and optimal lubrication reduces operating temperatures, increases component life and improves efficiency.

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