I have had my 1992 4x4 S-10 Blazer for about 3 years with no trouble at all.
However,
this winter season something weird is happening in the 4 wheel drive system, and
I
actually know very little about them. I'm hoping I can describe the trouble and
maybe get
some ideas what to look at. Up in these parts a decent mechanic is rare, I
don't trust most
of them, the dealership that I didn't really trust is now on the brink of
bankruptcy and has
no inventory and most of the experienced mechanics have left. So..help if you
can!

I generally use the 4 wheel drive only a few times in the nice weather,
generally to climb a
hill to maintain a radio transmitter. Over the past good weather season the
couple times I
needed it, it was fine. About 6 weeks ago we took a trip to Minneapolis after a
lot of snow
and ice, so I used the 4 wheel drive for about 100 miles or so on the drive. i
noticed when
I shifted the transfer case into 4 wheel high that the little lights that light
up the front tire
picture on the console did not come on all the time. Specifically, it seemed
they would
illuminate when I was under load, but would go out when I was coasting, or let
off the gas
a bit. However, the 4 wheel drive seemed to be working just swell. Upon
arriving in the
city, I switched back to two wheel drive and noticed that the front wheel lights
did not go
out. They remain on when driving in the city, go out at highway speeds, and
come back
on at hiway speeds under load. So, basically the lights for the front tire logo
come on and
off with engine load at speed, and stay on in town. However, when I shift from
2 to 4
wheel and back, I can tell that the truck is actually changing from 4 to 2
wheel, but
something is very much not right.

Further, if I drive at hiway speeds with the selector in two wheel drive for any
distance..10
miles at 65 mph for example, *sometimes* (rarely) when I slow down to 40 coming
into
town I get a horrible whining gear sound that gets louder as I slow down, till I
get down to
about 30 and it goes "foomp" and the sound goes away and all seems
normal....except of
course the front wheel lights stay on, telling me I'm in 4 wheel drive, when I'm
not. this
does not happen if I leave it in 4 wheel drive, but I seem to notice a bit of
increased
vibration in 4 wheel. Also..it *seems* that the consonle cover gets quite hot
(hotter than
the air coming out of the heater for example) after about 10 miles in 2 wheel
drive on the
hiway.

As I said, I really don't know much about the system, how it works, or the
actual meaning
of the 2, 4, n, and 4 lo lights (I mean, I know that they mean I'm in that
respective mode,
but what is physically happening in the system I don't know) as opposed to the
little lights
for the front wheels in the little diagram on the console. But something is
wrong, and I'm
forced to drive it 10 miles each way to work and I'm worried that I'm slowly
destroying
something. All I have done is check the lube in the differentials and transfer
case, which
are full. I also noted there were a couple fuses marked in the fuse block that
had
something to do with 4 wheel drive, something for a control module and something
else..both are good.

Any clues as to things to look for would be of much help. Any ideas? Hope I'm
not too
redundant but I will post this to another appropriate group as well. I have
auto
transmission and the V6 if that helps. About 120,000 miles on it. Never really
used for
offroading or any really abusive uses.

Thanks in advance for any help!

Tim in Bovey, Minnesota

its too bad you arent near an Aamco Transmission place that would
give you a free diagnosis.. honestly, ive had some concerns with my
4 wheel drive as well, but not with the lights.. sometimes its
difficult to put into 4 wheel drive mode and back into 2 wheel
drive.. i have very little troubles in 2 wheel drive, but sometimes
it seems 4 wheel drive i get a noticeable shake or grinding
sound..and a few times, i could barely reverse in 4 wheel drive..
but ive taken it to aamco on several occasions and all theyve really
noticed wrong is the transfer case leaks a little bit and that i
should get it serviced, which i havent.. but i have the fluid
changed much more frequently than recommended and checked out for
other issues.. thankfully, it does ok except for an occasion shift
problem..

you could call an aamco facility and give them your symptom over
the phone and see what they say, but im sure theyd have to have ya
bring it in and looked at.. but generally, theyll give you a free
diagnosis and estimate..

good luck..

jt

ok for the first guy, check out the sensors for the 4wd unit. and as to the
other problems, it sounds like it might be something with your driveshafts,
maybe the u-joint or bearings.

kurezi1