2023 Jeep Grand Cherokee — Transmission & Axle Gear Ratios

Transmission gear ratios

The 2023 Jeep Grand Cherokee (WL, two‑row) was offered with two propulsion families: the 3.6L Pentastar V6 and the 4xe plug‑in hybrid. Both use 8‑speed automatics with the following internal ratios.

8-speed automatic (850RE) — 3.6L Pentastar V6

8-speed automatic hybrid (8P75PH eHybrid) — 4xe PHEV

Note: The hybrid uses the same basic 8HP family gearset with an integrated electric drive module in place of a torque converter. Internal ratios are effectively the same as the conventional 8HP set used behind the V6.

Available axle ratios

For the 2023 two‑row Grand Cherokee, axle/final‑drive ratios vary by powertrain. Most V6 models carry a 3.45 ratio; 4xe models use a numerically higher 3.70 to support the hybrid’s torque curve and towing. Always confirm by VIN/build sheet.

Tip: The three‑row Grand Cherokee L (WL75) with the 5.7L HEMI used a different configuration and often a different axle ratio; this page focuses on the two‑row WL74 for 2023.

How to identify your axle ratio

• Mopar build sheet by VIN (best for Jeep): Enter your VIN at Mopar’s official “Equipment Listing/Build Sheet” site or ask a Jeep dealer to print it. Look for the line item “Axle Ratio x.xx” and any differential options (e.g., Quadra‑Drive II with electronic LSD).
• Window sticker: Many Monroneys list “Axle Ratio x.xx.” Owners can retrieve the original sticker by VIN from various online archives.
• Axle tag/label: From the rear of the vehicle, inspect the differential. Many Jeep axles have a metal tag or an adhesive barcode label on the axle tube or a diff‑cover bolt. The tag typically shows the ratio (e.g., 3.45) and build date. Clean the area to reveal stamping.
• Spin test (no tag present): Chock the front wheels, raise the rear axle safely, mark the driveshaft, and rotate a tire two full turns while counting driveshaft revolutions. ~3.5 turns ≈ 3.55 (close to 3.45), ~3.7 turns ≈ 3.73 (close to 3.70). Limited‑slip may require turning both wheels together.
• VIN decoders: Some third‑party VIN decoders and Jeep forums can identify the ratio by option codes; always cross‑check with the build sheet.
• For reference on other makes: GM products use an RPO code label (often in the glove box or driver‑door jamb); Ford and Ram commonly list the axle code on a diff tag or door sticker. Jeep does not use GM‑style RPOs—use the Mopar build sheet instead.

Towing vs MPG impact

• Lower numerical ratio (e.g., 3.45): Better highway fuel economy thanks to lower engine rpm in top gear. Example: 8th gear 0.667 × 3.45 = 2.30 overall ratio.
• Higher numerical ratio (e.g., 3.70): Better launch and grade performance for towing/hauling. Example: 1st gear 4.714 × 3.70 = 17.44 overall, about 7% more wheel torque than 4.714 × 3.45 = 16.27.
• Real‑world: If you tow frequently in hilly terrain, the 3.70 of the 4xe keeps the engine in its torque band and reduces gear hunting. Long‑distance, lightly loaded highway driving favors the 3.45 V6 setup for mpg.

Common issues

The WL‑series Grand Cherokee driveline is generally robust, but technicians commonly see:

• Ring and pinion whine: Most noticeable 45–70 mph on light throttle/overrun. Check gear pattern and backlash; verify correct 75W‑85/75W‑90 synthetic gear oil fill.
• Pinion seal seep: Early weeping can be addressed with seal replacement and vent inspection.
• Limited‑slip clutch chatter (Quadra‑Drive II): Often improved with fresh fluid and the appropriate friction modifier; complete clutch service if persistent.
• 8‑speed service notes: ZF‑family units prefer the correct ATF (Mopar 8&9‑Speed ATF or ZF Lifeguard 8 equivalent). Adaptations may require a relearn after major service.

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