Chevrolet Repair: 4x4 engage, cold north, great shape

Question
Van,
I saw your website regarding the problems that the person was having with their differential acuater that caused the front wheels not to engage when put into 4 wheel drive.  That is the problem that I'm having.  When I put the truck into 4 wheel drive the front wheels don't engage.  I is cold here and it seems to be making the problem worse.  before I would have to rock the truck softly between drive and reverse to get it to engage.  
Question: Is there any maintenance that I can do to make this work properly?  I bought a southern 1995 Silverado and have it the cold north now. Great shape but 4x4 does not like to engage.

Answer
Hi Phil,
The orriginal actuator was, and may still be, a thermal actuator, that wasn't intended to engage instantly. They took several seconds.
Yours may be working fine, but the replacement actuator will engage much more quickly.
I still have several of the thermal ones in service in my fleet, and will only replace them if they give a problem.
Till then, we just anticipate when 4X4 will be needed, and shift a little sooner.
See if that works for you.
Van