4x4 problems

[reginald fairfield]

I have a 99 ford ranger with (gosh dern it) vacuum actuated hubs. I hate them, as does everyone. I am having problems with the 4x4, and I would appreciate any help that any of you can supply. Here is what it is doing.

It all started one day when one of my friends got stuck in their chevy 3/4 ton. I tried to pull him out, so I put it in 4 low and goosed it. His pickup hardly moved, but my pickup started lurching out of 4 low really quick and then jumping back in. It messed up something, but I have no idea what. I originally thought that it was the chain in the transfer case being loose, so I had a new one put in, but it still does the same thing. I am now thinking that it could be the hubs. The hubs have another problem. Whenever I drive my pickup for a fair distance and time, (say 45 minutes and 100 miles) the hubs simply do not engage, period. Maybe the hubs got stripped, and some shavings are clogging the vacuum lines. I am sick of it not working. Anybody have any ideas or experience with this problem?

 

[MAKG]

It's lurching out of LOW? It has to be in the transfer case, or forward. Low range is controlled by a planetary gearset in the front of the transfer case. The chain does NOT participate.

A possible reason is shifting into LOW while moving. Rounded splines and all that.

IF it's not just variable traction.

Bad hubs and so on may disconnect 4WD, but it won't affect low range.