1997 geo tracker with manual hubs keeps jumping out of 4 wheel drive.

I got this free Pdf manual from reliable-store for free and I don't think Ive visited a mechanic or fixya for help for more than 3-4 times out of the 20 times I fixed the chipper in these 4 yearsmust try this bitman and reliable-store. Both are good

For Trackers (and Sidekicks) of this era (1989 to 1998) the front axle locking device is a locking hub on each front wheel. (There are no actuators until the model change in 1999.) Locking hubs come in two flavors, Manual and auto locking hubs. A look at the from wheel should tell you what you have. Manual hubs have a knob like lever with the word "lock" and "free." Auto hubs say "Auto-Locking" right on them. Both types of hubs require servicing periodicity. (Normally annually.) This means removing and disassembling. Then cleaning and light greasing before reassembling. There are some good videos on the web on how to service the manual hubs. Auto hubs are a little harder to ensure they are working properly, but some people like them. (Not me.)

Please note two things:
1. Due to differential action, BOTH hubs need to be locked for any power to be applied to the front wheels.
2. Trackers of this era are PART TIME 4x4, NOT all wheel drive. They have nothing providing for different wheel speeds front to back like a center differential. This means they should NOT be used on non-slippery surfaces like dry pavement. Beside causing handling and braking issues, it can destroy your transfercase driving on dry pavement in 4x4 due to what is called "driveline wind up".

PLEASE if you do not understand this, look it up... if you still do not understand, ask and do not use the 4x4 until you do.

old post
and common, prob.
it can be just the wear markets on the front pads yelling at you
"change me" soon for i die.
or the 4wd axle ends lockers are rusty and clicking. (common)

both the hubs and bearings are here.
http://www.fixkick.com/hubs/FW_BEARINGS.html

you can in fact remove just the auto/manual locking hubs
and drive, to prove they are good or bad. (easy huh)?

Bad transfer case

old post
all 96 trackers 89=98 for sure)
the hubs are a 15k service point
they are bad, if automatics
or need service if manual locks.
in the box
type hubs
http://www.fixkick.com/

bingo city

if it is in 4 low it will lug also in 4 high if excessive u-joints could be dry and binding or just needs to be ran in 4 wheel for a few miles to lube everything up bearings gears front axle etc... be sure transfer case is full and differentials are full also you need to have same size tires all the way around.

One of you can break down and buy a 3 dollar owners manual from a used manual vendor on ebay and make a copy for the other. Then both of you could read it and have the answers to many questions, including this one.

You need to take the cover off your hub and clean and grease the lock ring. It is attached to the spring. It sounds as though your hub is rusted open.

My son tracker o into 4 whdr. then jump out of 4 wh.dr. going down the road when he needs it.

Does it have manual hubs? If so, try disassembling the hubs and cleaning them. This happened to me after a while. I try to engage the 4WD at least once a month for 5-10 minutes on a loose gravel road to keep everything moving.