Hi, we were finally able to successfully change the automatic transmission FLUID on our 2015 Cherokee.
There was so much contradiction and various transmission combos and access points as well as many omissions and mission steps! Such that I had to piece the procedure together and create my own how to notes(sharing below) afterwards, for anyone who is going through the same thing. I am not a professional and I am not an expert. Yet I do try to be thorough and accurate in my sharing. Below is what worked for us and what my understanding is thus far. Don't blame me if yours might be different.2015 Cherokee w/3.2 v6 “Pentastar”, AWD(Active Drive 1), ZF 9 speed transmission(9HP48 ),transfer case & front & rear differentials. W/Optional trailer tow package(dual(not single) piston caliper w/larger-pads front brakes, etc).
-Transmission fluid & other fluids:

Change(PERFORM EVERY 60K MILES or sooner for severe duty. If you have gone much longer than that, after changing and driving the vehicle say 10k miles, do perform another transmission fluid change).



Procedure for 2015 (2014-19 same?) w/Cherokee’s w/9 Speed ZF Auto transmissions, 3.2L=9HP48 trans.

USE Valvoline Maxlife Multi-Vehicle ATF(NOT ATF+4-don’t buy) @ Walmart etc.!(NOT the ATF +4 fluid).

Transmission in total Holds 9-9.5 QTS, BUT you can only Drain & Fill the sump, which holds Only 4-5 QTS.



*NOTE: Models with 4/All wheel drive(aka “Active Drive ..”), also have 2 other components with fluids to check/top off & possibly change if able(read on):

#1, the DK4 P.ower-T.ransfer U.nit-Case. Located behind the engine oil pan(Sends power to the R.ear D.ifferential M.odule unit) &

#2, the RDM’s double compartment oil sumps.

Notes: The front differential is integrated with the PTU and therefore the front differential gets no separate fluid/sump.

In the efficient-normal mode(system has not detected a slipping surface I.e. rain, snow etc), these vehicles are front wheel drive. Rear wheels are activated when automatically called for.



Procedure for PTU(modern transfer case)& Differentials.

(For Transmission-See further below).

Notes:

These all use 75w 90 GL-5 Full Synthetic Gear Oil.

None have a drain plug Because:

These units normally only need:

Metallic debris cleaned from the inside of their magnetic fill plug.

Their fluid condition checked,by dipping your finger into the hole & then finger wiping onto a white cloth/paper towel.

Also topping off of the oil if low at all, and check for leaks.

To add oil into their small fill holes, you’ll need a pointed tip squeeze type bag-bottle or a hand pump.

These do Not need gear oil changing for their life. With normal moderate driving, say at 100k miles, the top of the gear oil is surprisingly clean/still light amber in color, with strong/fresh additives smell.

This is because of several modern changes such as: sealed units(no air-oxidation transfer & no moisture can enter), precision machining, turned off most of the driving time, full synthetic oil.

HOWEVER, with more miles, there can be sludge and wear particles in the lower end of the unit which will accelerate internal wear.

It would be wise to change the gear oils every 150k miles at minimum. Which may double the expected (approx. 200k miles) life span of these unites.

However both the PTU & the RDM’s passenger side sump plug hole have internal gears mostly blocking insertion of reverse pump hose. Although the RDM’s rearward driver’s side sump hole does allow a hose insertion, enabling reverse pumping out the old oil for fresh.

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The Fill Plug: Located on the passenger side of the PTU, positioned about at the centerline of the unit, covered with a heat shield(10 & 13mm hex bolts).

The last top shield bolt is inaccessible so move the shield away some). Use common a 3/8” square ratchet end to unscrew the plug. Do not over tighten the plug when reinstalling. These plugs have built in sealing washers so no Teflon tape is needed on the plug threads.



PTU & Note:



(If the old fluid smells sweet, it might actually be ATF fluid which different design models can require.

In that case, your jeep is differently equipped than the 2015 Cherokee model discussed here. You’d need to find a procedure that matches your design).



Simply remove upper Driver’s side fill plug & remove drain plug(use an 8mm(or 5/16”) Allen socket) & drain. Reinstall drain plug, after adding leak proof Teflon tape to plug threads(do NOT over tighten a plug). Hand pump ATF fluid into fill hole until it drips out. Reinstall fill plug w/teflon tape on threads.

Note: Differentials: Instead, !:

Front differential (1.5-.6 QTS) & Rear(4 wheel drive models only)(2.2-.3 QTS).

Rear Differential Fill Plug: 26 Ft. Lbs., PTU Fill Plug: 30 Ft. Lbs., PTU Heat Shield: 10 Ft. Lbs.

Friction modifier Note: No Cherokee models offered a mechanical clutch type LSD. So NO bottle of friction modifier additive required. In fact a friction modifier can interfere with a Trail-hawk model’s “Active Drive Lock” electronic LSD.



A major cause of failure of the RDM & Especially the PRU is driving with 4 tires which were Not replaced at the same time.

Always replace all 4 tires with New, at the same time with the same brand and amount of wear. A difference in the overall diameter of any of the tires compared to the others, will cause activation of the clutch packs and on dry surfaces, causing them high stress and wear.



TRANSMISSION FLUID CHANGE PROCEDURE:

9 speed(Note: 8 speed found on other Jeep models, the fill level procedure is Not the same/applicable.)

Ref:

You Tube

1. REQUIRED: Allow the engine to cool down somewhat. The transmission/fluid must not be too hot.
2. Using wire of a coat hanger, cut to about 7.75”, bend into the following small dip stick: The Long straight end must be 140 mm(14 cm) long. So it has a straight long wire tail of 140mm and then the following L bends are above it: Bend an L hook “stop handle” on the top end of the “dip stick” wire. More detail: make the L stop handle: 2 flat sides(1 perpendicular and one parallel to the long end), about 1” each. The long straight end of the stick, starts abruptly, after the 2 perpendicular bends. Rough file the first several inches of the wire bottom end so the fluid will stick/level will be obvious to see. The hook will be inserted to rest on the check plug opening with the long tail inside to touch-measure fluid level. Then extract to measure.
3. Wear Disposable GLOVES. Turn engine off.
4. Set the emergency/park brake.
5. Chock rear tires(with a rock etc). Loosen Only the front driver’s wheel lug nuts.
6. Using a jack and stand, placed under the lower control arm, close to the tire: Jack up the driver’s front wheel, just until off the ground. So that the front of the vehicle is still relatively level.
7. Remove the front driver’s side tire. Leave the pass front tire & lugs on!
8. Start engine & turn the steering wheel all the way to the left. Then turn engine off.
9. Access the transaxle-rearward’s “check & fill” bolt plug, from the driver’s side wheel well.
10. It is Not the somewhat lower diagnostic plug which is close to wheel well area. The plug you want, you must reach deep into the wheel well by the steering strut bellows.The bolt is on top of a rearward metal ledge surface.
11. Remove the plug using an 8mm(or 5/16”) Allen wrench socket. If for some reason you can not remove it, do not proceed to the draining step.
12. For good access to the bottom drain plug, you will probably need to remove the plastic under engine cover. Use a 10mm socket.
13. Using a 10mm Allen wrench, loosen the transaxle’s bottom/obvious drain plug.
14. Place drain pan under and remove plug. Clean plug & area & reinstall the plug, torque to 26 ft. lbs.(do not over tighten). The plug has a built in washer so no Teflon tape is needed on the threads. Which presents a hazard to the transmission if the tape enters it upon the next draining.
15. Accurately measure the amount of fluid that drained out. (A used plastic oil container with side measurements etc).
16. Insert a hand pump tool, adding new fluid to the approx. same quantity that previously drained out.
17. Clean & reinstall the plug loosely.
18. Start the engine. With a foot on the brake pedal: Idle for 1 min and then shift manually through all the gears(assures trans valve body passages are full of fluid), pausing 2 seconds in each gear. Now shift into park. Leave engine running.
19. Using display panel on the instrument cluster and the left side select buttons on the steering wheel, select the “#2 Vehicle Info” & down to “trans. temp”. Press the OK button to display. “Vehicle Info” will display after 5 sec.
20. Using up/down arrows button, select “Trans. Temp”.
21. Again remove the check & fill bolt plug.
22. With engine idling in park/neutral.
23. As soon as the trans temp climbs to 122 F, min.(212 F max), Insert the cut off coat hanger’s long tail, so that the hook is resting outside the plug hole.
24. Pull the wire out and measure the fluid level. Review chart below against temp display.

IMG_4632.PNG

1. As needed, add small amounts using a pump. Until desired chart level is achieved. (Also for cross referencing, consider how much old fluid came out).
2. Reinstall check/fill plug and torque to 17 ft lbs.(do not over tighten).
3. Assure there are no leaks.
4. Reinstall tire, torque lug nuts to 100 Ft lbs.
5. Remove both jack stands and wheel chucks.
6. Change fluid again in 60k miles.
7. Check/service the other fluid levels as mentioned above.

Take care