I have a 1999 ford ranger 4x4 ext cab and it has problems with engaging in 4x4. So far that it seems, the front driveshaft turns fine(just replaced), the differential is turnning the cv joints(the cv joints are new too), but I still cannot get this thing to go into 4x4. It engages by hitting the switch on the dash and the rest supposta be vacuum. Does anyone have an answer to help with this or A way to change this thing over to make it manual lock-outs.???? And the hubs are new too--so the rubber seals are good and in place.........I need help...............

AVM manual hubs. They aren't all that strong though. Manual hub swap. Available here.

You can always lock the stock ones in permanently. How to lock vacuum hubs

Also check the connections and lines to and from the vacuum ball that is on the passenger side splash guard.

__________________
2010 Magnetic Grey Metallic Toyota Tacoma Double Cab TRD offroad 4wd

I had the same problem with my 99. take the auto locking hubs off, if they are unlocked you should be able to turn the teeth freely, push the center down to lock them(the teeth should not turn) put the hubs back on in the locked position, that should hopefully solve your problem..
i had my wheel bearings replaced at a shop and they didn't put my hubs back on right took me about a week to figure it out and 10 miniutes to fix
hope this helps.

__________________
1999 ranger 4x4 supercab, 4.0L
-3 inch PA body lift
-16 inch pro comp alloys
-33x11.50 BFG all terrain
-Go Rihno roll bar with 4 KC Daylighter lights
-weston bull bar
-dual exhaust,
-air box mod, tightend throttle cable.

Thanks guys, I've been kickin myself in the ass trying to figure this out and no-one around here seems to know. Oh Ya, the ford garage does and for 75.00 they will look at it. LOOK AT IT. Not fix it, that cost more.I will try big greens idea first and if that doesn't work, I guess I'm on my way to ordering the manuals. Two more questions though--Big green, do you put your 4x4 switch on to 4x4 high-low before you do this? Or just leave it off? And whippersnapper02, what do you do with the vacuum lines once you install the manuals? plug it up, as there should be no need for vacuum no more...... Thanks again guys, I'm sure I'll be on here more now that I know this forum exists........

just leave it in 2wd, take off the hubs try to turn the teeth if they turn freely it is in the unlocked position, put your thumb in the center push down hard it should make a click and it will lock and the teeth wont turn ( if the teeth still turn freely push down again till they are locked), then put the hub back on...
when you switch it into 4wd do you hear it switch (like a click or clunk)? and when its in 4wd do the driveshaft and drive axles spin? if they do it is engageing the 4wd but your hubs arent locking the drive axles.. i had this problem...

__________________
1999 ranger 4x4 supercab, 4.0L
-3 inch PA body lift
-16 inch pro comp alloys
-33x11.50 BFG all terrain
-Go Rihno roll bar with 4 KC Daylighter lights
-weston bull bar
-dual exhaust,
-air box mod, tightend throttle cable.

i had this problem with my truck, the vaccuum lock hubs are infamous for it, my temporary fix was to permanently lock the hubs but it was hurting my gas mileage so i bought the AVM hubs from tellico4x4.com, although they are now called rugged ridge hubs, they work great though, i have had no problems with them, i don't know what you have done to your truck but if you have bigger tires on it, say 33-35 inches, the hubs will have trouble, they aren't built for that kind of stress

Done big greens idea and now it works fine but I'm still going to but the manuals for a back-up...... Good looking guys and thanks alot.

Yeah just get rid of the lines and plug up the ends because the vent run off of the same vacuum source.

__________________
2010 Magnetic Grey Metallic Toyota Tacoma Double Cab TRD offroad 4wd

There is this plastic cap on mine that I cannot get off - how did you get yours off? It has these tabs that lock it in and I cannot get all those tabs to release at once???? Do you have any step by step directions on this?

you can use a screwdriver lift 1 tab up and pull pull the hub till it moves a little, and just repeat for the other tabs. it should slowly come off
(easier if you take the wheel off)

__________________
1999 ranger 4x4 supercab, 4.0L
-3 inch PA body lift
-16 inch pro comp alloys
-33x11.50 BFG all terrain
-Go Rihno roll bar with 4 KC Daylighter lights
-weston bull bar
-dual exhaust,
-air box mod, tightend throttle cable.

reviving this old thread. I am trying to understand how this 4x4 system works and what happens when you do Big Greens fix. We are talking about the pushbutton vacuum system right?. this system has a vacuum line going to each wheel correct?. is the wheel bearing and vacuum system all one unit or are they separate?. when you lock the hubs the way Big green did it this means that both front wheels are always under power right? Does this wear anything out.? When the vacuum system breaks what is usually the issue? Are there sealls in the hub that leak vacuum out? thanks in advance

__________________
2004 Ext Cab, 4WD, 4.0, Auto, 154k. (4.0 engine is out of a 2009 Ranger w/96k) ( as of 7/1/2017)

2004 Ranger, Ext Cab, 2WD, 3.0, 5 speed , 4WABS, crank windows, no cruise, Edge 116k.(6/5,2014) (SOLD).
1999 Ford Ranger, Reg Cab, 2.5, 5 speed, 2WD, no AC, 150k (SOLD).

Were the hubs easy to put on. i am thinking about doing that to my ranger becuase i am having the same problem.

__________________
ranger with 33X12.50 all terrains with torsion bars turned up all the way and a 3" block in the back, intake, and flowmaster 50 series with duals.

Did this quick fix on my '98 Splash and now I have 4x4. Thanks for this info, I really appreciate this forum there are many tidbits of information here. This should hold me over till I can get my new hubs installed!

I have 1999 xlt It will engage into 4HI but I can not get it to go into 4LO. I follow the instructions in the manual but nothing happens. Is there a common problem that would make this happen?

__________________
99 XLT 4X4 3.0L FLEX

IM having the same problem, if I permanetly lock in the stock hubs, will I lose gas mileage? If I go to the avm, rugged ridge hubs are they hard to.install? If so where can I get directions to install them? Need help!