I have a 98 4.6 manual with a manual transfer case and it has decided lately not to cooperate. It started in the fall and has been progressively worse, I haven't been able to get it to engage since early January. I try to engage any type of 4 wheel drive and the light won't even come on in the dash with a few random exceptions but I am sure that the only time it dose actually engage is when the light comes on. I can easily spin on dirt when the transfer case is in 4hi or low but the light on the dash doesn't come on but when the light is on the truck jumps forward. Also it seems that if its in 4 low with the light off the rear wheels are in low while the front just isn't engaged.

The interesting part of this is that this problem seems to be related to the problem I have been having with my windshield wipers. The infinite settings on my windshield wipers no longer work but the three highest settings still will work if you understand what I mean (there are infinite settings on the first 2/3 of the *** but the last third or so is divided into three settings which sort of click into place. I wish I could describe it better but most of you should understand.) But I realized the last time that I got the 4x4 to engage that while it was engaged the windshield wipers worked perfectly, I also realized at that time that this problem also started sometime in the fall. I mentioned this to my mechanic but he could not find anything that would tie the two together.

I took it to Ford who told me that nothing was wrong and my mechinic who although couldn't fix it at least recognized there was a problem. He checked all of the vacuum hoses, and he checked and lubricated everything he could think of which makes him think its electrical but I'd rather not have to pay Ford to go through it again and tell me it works fine even though it doesn't. Any ideas would be greatly appreciated.

 

I have the same problem, only 5 times, for the past 4 years
all of a sudden the wipers only work on high speed,no
ranges. check the 4x4 and nothing happens...
come to find out Ford has a problem with some switch down
on the trans case that moisture gets into it....they just
changed the procedure for what parts get replaced,
however this still does not work. So for the 5th time
I will need to get this problem fixed...thee is some technical
service bulletin out there for this....its under 4x4

 

Thanks, I figured I couldn't be the only that had this problem. I'll see if I can find that bulletin, hopefully I'll have better luck fixing this permanently than you have.

 

By any chance do you know the parts (part #s if you can) that are supposed to be replaced??

I had my mechanic check his TSB DVD but he couldn't find what you mentioned.