I have a problem with my 4wd. Actually, two problems. I noticed the other day (while pulling out out of a snowbank) that my front wheels weren't spinning. The indicator lights don't work, and I've never actually seen them work, so I consider them useless. Now, I skipped a troubleshooting step and went right to the mechanical cable between the diaphram and gears, there is no play at all. I guess my question goes out to anybody who has played with the cable. Should it be movable by hand? If not, I will proceed to check the vacumn switch,lines and so on. Thanks.

"Sorry Man, I didn't mean to drive over your Honda."

<font face="Comic Sans MS">The cable should be easy or at least relatively easy to move by hand. [img]/wwwthreads_images/icons/crazy.gif[/img] Did the 4x work before without the indicator lights? If not then that's the problem. The indicator lights (for the little truck diagram) are operated by a sensor right on the differential itself that seems to sense when the mechanism moves. It would make sense that it doesn't come on since the linkage is apparently not moving... [img]/wwwthreads_images/icons/crazy.gif[/img] You're probably going to have to pull the cable out and see what's wrong in there... [img]/wwwthreads_images/icons/crazy.gif[/img]</font>

Tim "Sandman"

ORC Land Use columnist:
My February article on ORC
(I'm finally back)

I had a similar problem. I put the Truck on 4 Jack Stands and had someone slowly put the truck in gear while the shifter was "in 4WD". I pulled the cable into the Diaphram thing by hand, and bam! front wheels engaged. Turned out that the Diaphram thing had a rip in it. I actuall got a used diaphram in good condition from the local Salvage yard for free (while purchasing other small items). Good luck in tracking down your problem.

Rexxshelby
84 S-10 Winter Driver

rexxshelby
84 s10 Blazer 4X4 2.8 5 Speed

Thanks for the suggestions. The truth is that my truck diagram light is always on - 2wd or 4 wd. The only way to be certain the truck was in 4wd was to "feel" for it. This sucks, because spring is coming and after last summer, I'm convinced that spring is the only time you can find mud in this area. But anyway, your right about the diaphram, however I cannot budge this cable (while disconnected) at all. My buddy has a access to a garage with a hoist that he can rent ($6.00/hr - SWEET!) and I will be hopefully doing some serious troubleshooting this weekend. If anyone is interested, I will post the results.

"But Officer, I was only trying to gain enough speed to get over that hill up ahead."

the indicator light is activated by a swithch on your front diff, you can see it right where the cable goes into the front diff, if it is allways on then your front diff is allways engaged(not good) when it is up in the air, put it in 4x mode and if the front wheeles don;t turn, then try to stop your front driveshaft fron turning, if you can, your transfercase is shot, if you can;t then your front end is broken, thats what happened to mine, theres a little slider gear in there that contolles the front diff(slides passenger side to engage, driver to disengage) the thing is there is a really cheep flimsey retainer that helps slide the gear out of 4x, if that breaks your in trouble, then it is allways in 4x (front end engages) or allways out (front end not engages) or half way between, (front end half engaged makes funny grinding noise when not in 4x front wheeles not turning) thats what happened to me, i just need to get up in there and fix it.
if you do open up your front end, if you could take some pics and do a write up, it would be greatley appreciated, or if you live close enough i could come help you... I live in north west indiana.

Hope I helped

Tim

88 blazer
Like A Rock

Thanks for the info. I almost think that my biggest problem is not having a garage. The front driveshaft is turning, however the front wheels do not turn, I have watched the driveshaft spin while driving in 4wd (tricky but possible through the floor consule opening) so I'm thinking that maybe the gears are toast inside the front end. But that's only true IF the front gears are engaged as indicated by the light, however as I mentioned before the cable does not appear to be working. So I guess my first step will be to disconnect the cable at the front end and try to move the gear with needlenose pliers, if they will fit. If that works ok than I'll get a new cable. Yes, the indicator is on, but that could also be caused by the switch being stuck on right? From what I've seen in these posts, most everybody has these problems from time to time, I think the GM engineers had too much time on their hands when they decided to take a mechanical shifter and a mechanical acuator and connect the two with a vacumn system.
Anyway, I will see what I can do. I couldn't get to my buddy's garage today, so I'll have to try again next week. Later, G.
By the way, I'm in Nova Scotia, but I appreciate your offer to help Tim.


"But Officer, I was only trying to gain enough speed to get over that hill up ahead."