The Fordson Tractor Pages Forum

Brian,

What does HD really mean?

I grew up thinking it means High Detergent. I put 30W Shell Rotella T in my Dexta gearbox and rear axle. I was looking at the container last night and noticed it only says 30W, not 30W HD. But, elsewhere on the container it says Heavy Duty.

So is it Heavy Duty or High Detergent?[/b]

Bill,
I have moved your post into the main part of the board.

You are correct as far as I was alway taught about the letters HD when refering to oils. It designated the first diesel engine oil which actually had less detergent qualities than some of the modern engine oils.

There also used to be a Series 3 diesl engine oil which was designated HDD. This was a very high detergent and now most of the agricultural and diesel engine oils are up to this level.

The HD would only be important in the engine not in the gearbox and rear axle. Your standard oil would be perfectly OK for that.

I posed this question to the online Shell Rotella expert:

The specs for my tractor call for 30W HD motor oil in the gearbox
and hydraulic system. I am using 30W Rotella T in it. The question came up as to what HD really stands for. I grew up thinking it was for High Detergent. It was pointed out to me that the 30W Rotella container doesn't have the designator HD printed on it, but it does say Heavy Duty. So is HD High Detergent or Heavy Duty, and does the 30W Rotella meet the specs for 30W HD?

Here is Shell's answer:

We intend for "HD" to stand for heavy duty, but it is also a high
detergent oil, so we'd be covered either way in this situation.

Thank you for your interest in Shell Lubricants!

Regards,
Edward A. Calcote
Staff Chemist
Shell Lubricants US Technical Information Center



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