If the grade is to heavy - use low range then.
That's what I do all the time then.
EB is much better in low range at low speeds then in high range at low speed.
Manually shifted into 1st and TH but no joy! did not shift into AWD tho maybe that would help ???
yeah... I recall my 04 (NV5600/4:10RaR) would stay engaged all the way down it seems... havent really tried or needed it on my 20 yet.. Did save brakes for sure tho, I never in 100k miles put a set on it.