If all other shifts/gears work fine, that indicates operating pressure (front pump) is good. No indiation of B2 trouble, as that is DELAYED engagement--but then full/normal lock--at all times in forward gear.

I'm suspicious of something wonky with the bowden cable. It provides signal for coasting/downshifts as well as upshifts.

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James Marriott
2003 Buick Regal
1983 300D (228k, frau Auto)
1996 Suburban K2500 (192k, 6.5 turbo diesel/4WD towmaster 10,000)
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1987 300SDL junker 170k
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