Borg Warner WC T5 oil

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Author Topic: Borg Warner WC T5 oil  (Read 362 times)

Offline AussiePhil

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Borg Warner WC T5 oil
« on: July 24, 2020, 10:51:53 PM »
Hi all,
Sorry to bring this up again! But the main past conversation was back in 2013.
What is to current recommended fluid/oil for World Class T5 Borg Warner gearboxes.

As spoken about before, do we use Valvoline Gear Oil DuraGear 75W GL4 or Dextron lll.

I currently have in my 89 WC T5 Penrite ProGear full synthetic 75W GL4.

Just looking for current thinking!

Exert from MDL, confusing that they do not separate WC and NON WC well enough, How do you read this.

One last piece of important information.  ALL World Class T5 use ATF (Dextron III) oil and NOT heavy gear oil or Redline MTL!  All NON-World Class T5 use 50 wt gear oil. (The original Ford/Borg-Warner recommendation back in 1984 was Dextron II.  As this is no longer available, we and TREMEC recommend the 50 wt gear oil.)
We recommend high quality Synthetic oil as it lasts a long time and over a larger operating temperature.  It is important to change the oil in your transmission based on how you use the vehicle.  If the vehicle is your daily driver then changing the oil every two to three years is fine.  However, if the transmission sees regular track duty and pushed hard, then once or twice a year is in order.
When we rebuild transmissions, we can tell when the oil has been changed often as the parts are much cleaner with less over all wear. There is no filter inside the manual transmission only a magnet at the bottom to pick up the metallic particles in the oil, the only metallic parts in a transmission is the gears or bearings.  Oil is cheap, transmissions are not !

Cheers bigal and Shaun, you recommended Valvoline DuraGear 75W GL4.
How does the Penrite stack up against it, I am keen to change my oil at the moment and just want the best.

Cheers Phil.
« Last Edit: August 04, 2020, 12:56:37 AM by AussiePhil »
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