Etrex 10 & 30x - "Grade" data field

I can't find any reference to a 'Grade' field in any of the Etrex 10, 20, 20x, 30 or 30x manuals I have looked at dated 2011-2015, they do refer to Ascent (and Decent), Average, Maximum and Total rates, which may give you the data in a different format

 

O.K. so this is a new addition to the software, both new and older manuals have a warning that not all fields are available on all models, e.g. :-

But I would guess that the only feature you may need is a unit with an electronic altimeter that measures barometric pressure rather calculating altitude from satellite data, the error in the latter might make 'Grade' unusable because it would be too unstable.

The problem could be that the units you are using are not new enough to be compatible with the new software that has the 'Grade' feature, e.g. only available on 2019 models, how old are your units?, what date / version of software do they have?

 

I must admit I'm running out of suggestions, I would have thought if you pick a screen that displays Data Fields like this one :-



Select Menu >> Change Data Field then the selection window should include GRADE, I can't see an 'Add Data Field' so it may replace an existing one

I would be inclined to contact a Garmin help desk saying you have a Etrex 30x w/software version 3.0 and can't get it to display GRADE, it's worth a try