Jeep WJ Grand Cherokee Transmission Service & Maintenance

Welcome to the JeepSpecs.com in-depth page on WJ Generation Jeep Grand Cherokee transmission service & maintenance. We have organized as much information as we could find into a helpful article below. Is something incorrect or missing? Please get in touch with us and we’ll fix it!

FLUID CAUTIONS:

ATF+4® MUST always be used in vehicles that were originally filled with ATF+4®.

ATF+4® is compatible with ATF+3 and can be used to top off vehicles that currently have ATF+2 or ATF+3.

DO NOT use ATF+2 or ATF+3 to top off vehicles that have ATF+4® fluid

The use of non-recommended fluids can result in transmission failure. The usual results are erratic shifts, slippage, abnormal wear and eventual failure due to fluid breakdown and sludge formation. Avoid this condition by using recommended fluids only.

A low fluid level allows the pump to take in air along with the fluid. Air in the fluid will cause fluid pressures to be low and develop slower than normal. If the transmission is overfilled, the gears churn the fluid into foam. This aerates the fluid and causing the same conditions occurring with a low level. In either case, air bubbles cause fluid overheating, oxidation and varnish buildup which interferes with valve and clutch operation. Foaming also causes fluid expansion which can result in fluid overflow from the transmission vent or fill tube. Fluid overflow can easily be mistaken for a leak if inspection is not careful.

FLUID ADDITIVES:

DaimlerChrysler strongly recommends against the addition of any fluids to the transmission, other than those automatic transmission fluids listed above. Exceptions to this policy are the use of special dyes to aid in detecting fluid leaks. Various “special” additives and supplements exist that claim to improve shift feel and/or quality. These additives and others also claim to improve converter clutch operation and inhibit overheating, oxidation, varnish, and sludge. These claims have not been supported to the satisfaction of DaimlerChrysler and these additives must not be used. The use of transmission “sealers” should also be avoided, since they may adversely affect the integrity of transmission seals.

FILTER SEAL CAUTION (545RFE):

The primary oil filter seal MUST be fully installed flush against the oil pump body. DO NOT install the seal onto the filter neck and attempt to install the filter and seal as an assembly. Damage to the transmission will result. Install the new primary oil filter seal in the oil pump inlet bore. Seat the seal in the bore with the butt end of a hammer, or other suitable tool. Place replacement filter in position on valve body and into the oil pump. Install screw to hold filter to valve body. Tighten screw to 40 in. lbs. torque.

CHECKING THE TRANSMISSION FLUID LEVEL:

All WJ transmissions have a dipstick to check oil level. It is located on the right side of the engine (passenger side). The dipstick cap and fill tube should be wiped clean before checking fluid level. Dirt, grease and other foreign material on the cap and tube could fall into the tube if not removed beforehand. Take the time to wipe the cap and tube clean before withdrawing the dipstick.

MODEL 45RFE or 545RFE: (used with V8 engines only)

1. Transmission fluid must be at normal operating temperature for accurate fluid level check. Drive vehicle if necessary to bring fluid temperature up to normal hot operating temperature of 82°C (180°F). The torque converter fills in both the P (PARK) and N (NEUTRAL) positions.

2. The engine should be running at idle speed for at least one minute, with the vehicle on level ground.

3. Apply parking brakes.

4. Place the selector lever in P (PARK) to be sure that the fluid level check is accurate.

5. Clean top of filler tube and dipstick to keep dirt from entering tube.

6. Remove dipstick and check fluid level as follows:

(a) Correct acceptable level is in crosshatch area or area between “COLD” and “HOT”.

(b) Correct maximum level is to “HOT” arrow mark.

(c) Incorrect level is at or below “COLD” line. The fluid level will be approximately at the upper COLD hole of the dipstick at 70° F fluid temperature.

(d) If fluid is low, add only enough Mopar ATF +4 Automatic Transmission fluid to restore correct level. Do not overfill.

MODEL 42RE:

1. Transmission fluid must be at normal operating temperature for accurate fluid level check. Drive vehicle if necessary to bring fluid temperature up to normal hot operating temperature of 82°C (180°F).

2. Position vehicle on level surface.

4. Apply parking brakes.

5. Shift transmission momentarily into all gear ranges. Then shift transmission back to NEUTRAL.

6. Clean top of filler tube and dipstick to keep dirt from entering tube.

7. Remove dipstick and check fluid level as follows:

(a) Correct acceptable level is in crosshatch area.

(b) Correct maximum level is to MAX arrow mark.

(c) Incorrect level is at or below MIN line.

(d) If fluid is low, add only enough Mopar ATF +4 Automatic Transmission fluid to restore correct level. Do not overfill.

Transmission fluid, filters and service intervals

Transmission Fluid quantity Fluid & filter Interval A Interval B
42RE 4-6 qts. (service)9.5-10 qts. (overhaul) Mopar® ATF +4, type 9602Primary Filter (internal, flat):
P/N 52118789
($14.35 MSRP)(also adjust bands)
100,000 mi. 30,000 mi.
45RFEOR

545RFE

5.5 qts. (2WD service)6.5 qts. (4WD service)

14 qts. (overhaul)

Mopar® ATF +4, type 9602
Primary filter (internal, flat):
2WD – P/N 5015267AC
($21.35 MSRP)OR4WD – P/N 5013470AC
($21.35 MSRP)

Cooler return filter (internal, round):
2WD or 4WD – P/N 4799662
($16.95 MSRP)

 

 

100,000 mi. 30,000 mi.

TRANSMISSION FLUID AND FILTER SERVICE

REMOVING PAN AND FILTER(S) 1. Hoist and support vehicle on safety stands.

2. Place a large diameter shallow drain pan beneath the transmission pan.

3. Remove bolts holding front and sides of pan to transmission.

4. Loosen bolts holding rear of pan to transmission.

5. Slowly separate front of pan away from transmission allowing the fluid to drain into drain pan. A flat plastic trim tool can be used or carefully tap on edges with rubber hammer.

6. Hold up pan and remove remaining bolts holding pan to transmission.

7. While holding pan level, lower pan away from transmission.

8. Pour remaining fluid in pan into drain pan.

9. Remove single screw holding filter to valve body.

10. Separate filter from valve body and oil pump and pour fluid in filter into drain pan.

11. Remove and discard the oil filter seal from the bottom of the oil pump.

12. If replacing the cooler return filter (suggested), use oil filter wrench (Mopar #8321) to remove the filter from the transmission. (NOTE: 45RFE or 545RFE transmission only)

13. Dispose of used trans fluid and filter(s) properly.

14. Inspect bottom of pan and magnet for excessive amounts of metal. A light coating of clutch material on the bottom of the pan does not indicate a problem unless accompanied by a slipping condition or shift lag.

15. Using a suitable solvent, clean pan and magnet.

16. Using a suitable gasket scraper, thoroughly clean original sealing material from surface of transmission case and the transmission pan. NOTE: for 42RE transmission the transmission pan oil gasket may be reusable. Inspect the sealing surfaces of the gasket. If the sealing ribs on both surfaces appear to be in good condition, clean the gasket of any foreign material before reinstalling.

17. Let remaining fluid drain, the longer the better if you want to get more of the old fluid out.

FILTER AND PAN INSTALLATION

1. Install a new primary oil filter seal in the oil pump inlet bore. Seat the seal in the bore with the butt end of a hammer, or other suitable tool.

 

 

CAUTION: The primary oil filter seal MUST be fully installed flush against the oil pump body. DO NOT install the seal onto the filter neck and attempt to install the filter and seal as an assembly. Damage to the transmission will result.

2. Place replacement filter in position on valve body and into the oil pump.

3. Install screw to hold filter to valve body. Tighten screw to 40 in. lbs. (4.5 N·m) torque.

4. If changing cooler return filter, install new one onto the transmission. Torque the filter to 125 in.lbs. (14.12 N·m) (NOTE: cooler filter is only used on the 45RFE and 545RFE transmissions).

5. Place 1/4″ or so bead of Mopar RTV sealant onto the transmission case sealing surface (45RFE and 545RFE). For 42RE transmission reinstall gasket or install new gasket.

6. Place pan in position on transmission.

7. Install bolts to hold pan to transmission. Carefully tighten bolts to 105 in. lbs. (11.8 N·m) torque. Allow RTV sealant to set for 15-30 minutes (45RFE and 545RFE).

8. Lower vehicle and fill transmission with Mopar ATF +4, as described in the Fluid Fill steps below.

TRANSMISSION FLUID FILL

To avoid overfilling transmission after a fluid change or overhaul, perform the following procedure:

1. Remove dipstick and insert clean funnel in transmission fill tube.

2. Add following initial quantity of Mopart ATF +4 to transmission:

(a) If only fluid and filter were changed, start by adding 10 pints (5 quarts) of ATF +4 to transmission.

(b) If transmission was completely overhauled and the torque converter was replaced or drained, start by adding 24 pints (12 quarts) of ATF +4 to transmission.

3. Check the transmission fluid level and adjust as required by following the CHECKING THE TRANSMISSION FLUID LEVEL directions above.