What possible, or likely harm, would it cause to drive my 1993 Suzuki Sidekick in 2 wheel High (2H) with the manual hubs locked?
One of them is stuck in and I don't really have time to fix it right now. So, I was just gonna leave them locked in for a month or more.
I drive about 20-25 miles a day.
Thanks

My 1994 Tracker Owner's manual has a "NOTICE: Do not drive in 2H with the hubs in LOCK or you could damage the driveshaft parts".
Until I saw your post, I never really thought about it (or checked the owners manual) and have driven that way many times without problems. Sometimes I would lock the hubs in my driveway and drive 10-15 miles to where I go offroad and go into 4H or 4L then drive home the same way. During fishing trips I would go between fishing holes and come into and out of 4x4 and never unlock the hubs. Problems could occur with 4x4 on pavement, but I've never heard of problems with just the front end locked. My 2000 Tracker had full time hubs in the front until I changed them out with Superwinch so I could make them free wheeling when I didn't need to turn the front end hardware in 4x2 operation.
If its noted in the owner's manual, there must be a reason for it, but I'm not sure why.

I owned a ?97 for three years (just sold it) and always left the hubs locked as I was on and off unpaved roads. It didn?t seem to suffer any harm. I don?t know if it?s the case with Suzuki but some one once commented that on most 4x4s the front and rear differential and driveshaft compnants are the same so why should the front end wear out before the rear. Seems like the weak link would be the axle U-joints. Also none of the pre ?70s 4x4s American or Japanese came with lock out hubs.