00 x5 4.4 trans fail mode. gear 1 & 2 kick hard . code 59 stall monitoring & 8D TCM signal error. new battery. drop trans pan no metals, no smell...drop transmission check the clutch A no issue .

is REVERSE OK
is PRNDL ( is L okay)???

OK what is the correct order to test. for sure not that
the service manual covers that, for sure the TCM.
1: ;all fuses good ,every one.
2: next is scan the PCM why skip such a key step> here??????
what if speed sensors fail.?
what if load modulater fail in the box.
the transmission book there and ATSG books tell you that and tells you that pump pressure test ports must be at spec or upshifts fail.
if pressure is low (or vast reasons) it can not fully operater the 2nd gear Servo piston to do so,

see my crude drawing her. (older tech box but works same in principle.
do you know what Limphome means for engine and trans?
on the trans, the TCM brain see horrible errors ,(you ignore)
and goes to limphome mode on the box. just 1 year or 2,
depends on actual box model like 4L60? GM box.there?
not sure I will look it up. not saying I know all Limp modes on all boxes.
below the shift lever is now a bank of shift solenoids
but they do the same thing.
if pump and its regulator work and filter not packed up or sucking air
the pump will have spec pressure at idle and the stall load test
the speed sensors must all work and no P07xx errors allowed
even some engine fail can set the trans to limphome too.
the FSM covers that (factory service manual)

ahhhhh you have this transmission same as my wifes GC2010
4 Door; 5-Speed Auto W5A580 Trans. aka NAG1, and 722.6
I have full manual books on it. but not your TCM
or it has this box
42RLE

learn to decode your VIN and see what trans is there first.

and scan it. next after fuses.
The scans see it all, engine and trans both.
and must never be ignored.

Valve body problems. When engine heat starts to build in the fluid and metal parts inside the transmission, the valve body expands which will cause pressure problems.

To be honest get a new vehicle

Could be bad may you have to rebuilt it.

what could be>>> lots. are you asking just for wild guesses?
or asking for tests to do .>?
simple answer, RTM, read the FSM. it answers that.
longer:
no engine state , nor tranny model, that matches said engine.
bad A/T
The AT is complex device.
read the FSM (factory service manual) see that huge 100s of pages
just for one part of car. bingo,
one might say intensely complex.
so bad, many dealers farm out the work, after all on car test prove its bad. In fact, some manufacture, dictate that action.... (in warranty)

This A./T (no model stated (it has a tag) my be fully electronic
and as such has Tranny brain, called a TCM. (ASE names)
the TCM can be inside the PCM. (matters not)
the TCM is checked to see if it is infact shifting to R.
use a scan tool see if there are TCM errors, called DTCs.
any scan tool works here. older cars. even $9 tool (ask)
the FSM (or alldata.com) has a chapter with on car tests.
here are some... in shorst
1: check fuses. (it shows which)
2: scan it. got P07xx codes or others? post em.
3: Do the stall test, in Drive and REV. fails in REV only?
the test shows a spec. RPM for 1 to 3 seconds. does that pass?
then we check the pump pressure (@side ports)
and if reverse is bad, i check the TCM solenoid drive logic
with any volt meter, backprobing the side connector.
if the logic is right 0v. 12v then the TCM IS in REVERSE
and the TRANNY is bad.
some highly motivate mechs,, will drop the pan and test the REV. soleniod. (coil and valve)

1: even the gear shifter can fail, the PRNDL switch causing the
TCM to go nuts, yah, scan it again, bingo?
ford calls this the DTR.

the AX4 transmission has 5 solenoids to shift it.
3 shift , one EPC and one is TCC
0v is solenoid off, and 12v is on, the logic , shifts the trans.
the FSM shows a table and this logic, rules.
it takes only that table and a voltmeter to see if the TCM works.
the TCM is just a computer so if it has wrong outputs it will not shift right. if there are serious DTC error the transmission goes to
LIMPHOME mode skipping gears. (RTM)

alldata.com. login and read. and do the tests.
or get it fixed
there are only 2 choice, besides wild gue$$ing.

the DTR may not select Reverse. that is a possible.
and is a high failure item on all A/T cars.
its just a switch telling the TCM what you did.

d flash mans, tranny fault
so scan it. us the obd2 scan tool, any and scan it.
the A/T IS VERY complex, do the tests shown in the FSM
guessing dont work
but in general (experience)
wont shift correctly dont cut it. (200 parts, and 50 was to mess up)
????
flare, skips gears, wont up shift, wont down shift, or shifts wrong speed. what gears work, what dont. just a clue and help goes get better
The tranny TCM can go to limphome mode, this mode is very clear.
and covered in the FSM and
one common failure, that happens with high mileage and poor service (not doing a flush at 50k miles)
is stuck in 1st gear, hot. only.
the ATF fluid gets more thin hot and pump output drops
this is usually a vary bad sign.
the Stall test fails.
the pump pressure test fails, hot.
there is no vacuum lines to this electronically shifted trans.
the ended back 1990(about). with old 3speeds.

scan it, could be something slimple like
the PRNDL shift switch fibbing like crazy. (common)
this car has TCM, a transmission brain.
look for OBD2 DTC errors P07xx (trans)
this TCM (part of PCM) function relies on sensor for shifting
they are:
1: TPS
2: engine INPUT rpm
3: tranny output rpm
4: shift selector.
5: ECT (engine temps)
6: ECU part of the PCM calculates load at all times and sends that to the TCM , so that TCM can down shift on hills, or upshift faster on the flat or down hill.
this LOAD feature is what replaced the VACUUM of old days.

The D light , hopefully is just a bad input (cheap)
scan it. and see, its begging for you to do that.

ok , you google that and P0xx codes are a standard. federal codes.
and P07xx codes all are transmission.
so....
the A/T transmission, is a very complex system. "extreme"

http://engine-codes.com/p0758_honda.html

The computer (ECM/PCM/TCM) will not ever tell you what part is bad
it will only tell you which test is bad.
The TCM shifts the trans, and monitors the results at all times.......!

in this case. it shifted gears up, and the MPH speed, failed to rise
meaning the trans mission is slipping.. (for any of 100 of reasons)
it failed to shift at all (only you know) or slips (hidding the shift)

so id bet the car has high miles and the A/T was never serviced.
im i right?
why not do the service, (if slipping , this is the only hope)

why not read the FSM ?
read the on car checks.
1: A/T pump pressure
2: A/T stall tests. (slips is too high RPM) a 5 second test.
and the others....
or if all this is too hard?, take it in.

i have had luck replacing the solenoid packs on these models but i usually had a 12 shift or 23 shift code stored in the tcm controller

2001 grand cherokee?
nor years of all parts swapped.
swaps are super complex topics, endless possibles.

dont expect magic from any TCM.
they cant tell you ever possible way things can be wrong
it will fail to shift right if things are wrong,
the trans TCM can go to limphome mode, read the service manual chapter 21 yet its free, posted here 300 times.
forget the silly engine , light (CEL) use only a scan tool one that can read all factory codes not some $20 tool.
CEL lamp is for failing smog. only. never trust it, if out.

i say bad shift solinoids.
the TCM can see late shift error.s but maybe not all.
stick in 1st is a hard failure.
all inputs to the TCM must be correct for the shift to 2nd happens.
check all inputs.
if those are then see if the TCM did shift to 2nd, but the solenoids ignored the logic inputs to the solenoids.
solenoids have many failure mods
dead. (stuck closed)
stuck open, valve open.
or leaking. (leaking can cause stuck in 1st and confuse any TCM)

leaking means breached, valve leaks where it must not. ever.

P0733 IS GEAR RATIO ERROR IN 3RD AND P0734 IS GEAR RATIO ERROR IN 4TH..THESE CODES USUALLY MEAN AN INTERNAL PROBLEM IN TRANSMISSION,BUT CHECK WIRES AT SPEED SENSOR CONNECTORS FOR BROKEN WIRES BY PULLING ON WIRES AND WIRING NEAR SOLENOID PACK FOR CHAFING..I HOPE THIS HELPS..YOU MIGHT WANT TO DROP THE TRANS PAN AND LOOK FOR A PLUGGED FILTER OR DEBRIS IN PAN..MAKE SURE THE TRANS COOLER IN RAD HAS NOT FAILED ALSO