1999 Jeep grand cherokee limited with Quadra trac only works as two wheel drive when all wheel is selected and will not go into 4-lo. Sounds like it isn't engaging fully and feels like the lever should go back a little more but it won't.

so is AWD,? command trac or what trac?

no working means..... using or 4low,?
my wild guess: 1:
Quadra-Trac-II NV 247 Gerodisc system 1999+
got that? what you have for real MATTERS? we cant guess.
the 247 adds LimSlipDiff option to the system got that too>?
symptoms for working are>......
1: lamp dead.
2: lever stuck
3: tires x4 missing torque to earth?
1999 WJ jeep
4 steering binds up.?

say what is there.
and say what not working means , exactly
and say what tires are touching, (pavement , ICE or dirt)
we cant guess, road, either.

WJ jeeps.
what mode? 4h, 2l lock >?
why not just drive it and get it all loose and happy first.
get the gearlube hot, see if it wakes up, i bet it does.
there is no vacuum hose. that is part time. used long ago.
vacuum ended in 1995 with command trac.
the newer cars the front axle is cut out, inside the transfer case front end. ending vacuum and now electric.

Select track (stay off dry pavement in 4wd)
Quadra-Trac-II NV 247 Gerodisc system 1999+
Quadra-Drive NV247
if quada stay out of low or lock.

read this page,. and discover what you have.
or go under car, see that transfer case, see that silver and red tag
that is the NV number. what is yours>?
we can not guess options. ever.

http://en.wikipedia.org/wiki/Jeep_four-wheel-drive_systems

which one of 4.
http://www.wjjeeps.com/tcases.htm

First you need to check the transfer case fluid. It may be low or the wrong type. You need to go to the dealership to get the right type. It would be hard to go into more details without more info from you. Does both ranges not work? (4 wheel high and low)
Or is it just the 4 wheel high range that doesn't work?

are you on dirt? or pavement...????????????????????????
we cant answer until you answer what 4wd option you have.
if that makes no sense, then read the operators guide,
it tells you what's there and how to use it.
read that first, then ask questions,?
and if Part time 4wd?, it';s not to be used on dry pavement only ICE.

eg:

4WD: Select-Trac (or older Select-Drive has a slip coupling too, NP129/229) is AWD in that, "the "4Hi" setting the drive shafts were coupled together using a viscous-type coupler " this anti wind up slipper"
Watch out for exception 1: Select-Trac NP228 based jeeps, it does not have a viscous-type limited-slip coupling. It was used briefly in 1986.
Quada-Trac is full time 4WD (not in lock mode) has a real center differential to shift torque between front and rear. This is the best system , not just a slip clutch as above. Then went BACK to the slipper in 1980. (odd huh?) Up to 1998.
Quadra-Trac-II "4-All Time", "N" or neutral, and "4-Lo". In "4-All Time", torque is applied to the rear wheels under normal driving conditions.
If the rear axle starts rotating at a significantly higher rate than the front axle, hydraulic pressure builds up in the gerotor oil pump and causes the clutch pack, to progressively transfer torque to the front axle, until both axles return to the same speed
Quadra-Trac I was introduced in 2004-10, same as above but is automatic with no driver controls ,like above.
The Quadra-Drive system was introduced in 1999 and is based on the Quadra-Trac II system but adds limited slip differentials (the best full time system ,with great traction to all wheels all the time) 1999 to 04.
Quadra-Drive-II has electronic limited slip differentials or ELSDs 2005 up.

which system?
we cant guess what is In YOUR CAR, ever.
you must SAY. or RTM, in the glove box.
and why are you using 4wd on dry pavement, now>?


4WD: Select-Trac (or older Select-Drive has a slip coupling too, NP129/229) is AWD in that, "the "4Hi" setting the drive shafts were coupled together using a viscous-type coupler " this anti wind up slipper"
Watch out for exception 1: Select-Trac NP228 based jeeps, it does not have a viscous-type limited-slip coupling. It was used briefly in 1986.
Quada-Trac is full time 4WD (not in lock mode) has a real center differential to shift torque between front and rear. This is the best system , not just a slip clutch as above. Then went BACK to the slipper in 1980. (odd huh?) Up to 1998.
Quadra-Trac-II "4-All Time", "N" or neutral, and "4-Lo". In "4-All Time", torque is applied to the rear wheels under normal driving conditions.
If the rear axle starts rotating at a significantly higher rate than the front axle, hydraulic pressure builds up in the gerotor oil pump and causes the clutch pack, to progressively transfer torque to the front axle, until both axles return to the same speed
Quadra-Trac I was introduced in 2004-10, same as above but is automatic with no driver controls ,like above.
The Quadra-Drive system was introduced in 1999 and is based on the Quadra-Trac II system but adds limited slip differentials (the best full time system ,with great traction to all wheels all the time) 1999 to 04.
Quadra-Drive-II has electronic limited slip differentials or ELSDs 2005 up.

You need to be more specific. To start, which 4 wheel drive system your jeep has? (Select Trac, Quadra Trac II or Quadra Drive)
Then: does it never work, or only in 4-Lo?

a bad wheel speed sensor or not matching tires

universal joint on the driveshaft may do this !
check transmission fluide as well.
good luck

1st let me make sure I understand your Jeeps 4 wheel drive. I believe the quadra trac system is a full time 4 wheel drive, there is no 2 wheel drive setting, only a separate 4 Lo (for very slow speed). If this is correct, the problem is, the quadra trac system you have is supposed to compensate for any variations in wheel speed, whether it's driving in the snow, or cutting the wheels sharply to park on dry pavement. What u describe is typical behavior of a part time 4 wheel drive system. The problem is, your full time 4x4 should be compensating for this, and it's not. So, let me know if the above info about your 4wd is accurate (no part time 4wd setting, no 2wd setting, only full time 4wd and 4Lo setting. If it is, the system is not compensating for changes in the wheel slippage correctly.

sounds to me like the transfer case clutches are worn out. also the fluid could be low or dirty. try draining and refilling the transfercase with clean fluid. if it is still not working after driving it around for a few miles then you may need to replace or overhaul your transfercase