NP208 SOTF limits

[H2OnSnow]

My 82 K5 came with a 208 and auto locking hubs. It now has Warn manual hubs. The owner manual states NOT to shift from 2wd to 4wd at any speed greater than 25mph (??? I think that's the number). This makes a lot of sense thinking about the state of the front shaft, diff, axles, and t-case internals. All of those parts would be sitting still with no rotation. If you're running 65mph down the highway and get to snow and throw it into 4wd at that speed all those parts go from nothing to 65 spins in zero time. Not good. With manual hubs though, I could have them engaged when I'm in a situation where I might want 4wd. With the hubs engaged, all of those parts are spinning at the right speed already. I'm thinking that I should be able to safely shift on the fly when at speed in this case. My 2002 F250 had synchros and ESOTF and I could do this fine. The 208 has synchros but the 25mph limit. I'm thinking it's the auto lock hubs that drive the limit.

Does anyone have any specific info on this, or thoughts that I've missed?

 

[bucket]

I ran my auto hubs for a couple years. Pretty sure I shifted in and out of 4x4 at 55+ numerous times, but I can't swear to it anymore.

With the swap to manual hubs, I'd lock them into 4 wheel drive in late fall and unlock them in early spring. Lots and lots of shifing at higher speeds.