It is a std Ford feature – the filler plug is the level indicator same with their gearboxes. I should imagine that most manufacturers will have the same approach to oil level indication.
From: lotus-...@googlegroups.com [mailto:lotus-...@googlegroups.com] On Behalf Of Charles Helps
Sent: 01 August 2012 09:51
To: lotus-...@googlegroups.com
Subject: Re: series 1 eleven differential oil level
That's how it works on the majority of Mk VIs with the Ford Popular axle. One plug at the bottom to drain it and one on the side to fill it. I use a container with a bendy tube, fill until the oil reaches the bottom of the tapped hole and put the plug back in.
Perhaps an Eleven owner with the de Dion arrangement could confirm this.
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