ZF 9HP48 Problems & Specs

Ideally, a ZF automatic transmission will have a low enough first gear to provide strong acceleration from a stop, and multiple overdrive gears are used to lower engine RPM when the vehicle has reached cruising speed. A CVT transmission generally does this best, because it can instantly vary the gear ratio based on the situation. However, this type of gearbox does not traditionally work well with higher torque engines, or vehicles that are designed to go off road or tow trailers. The ZF 9HP48 transmission on the other hand, is a traditional geared transmission with a super wide gear ratio spread of 9.81:1. This means there are enough gear ratios in this ZF 9 speed transmission to provide excellent performance characteristics, without sacrificing fuel economy. Of course there are a few caveats with the design of the 9HP48 transmission, which we will explore now.

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What Transmission Do I Have?

9HP48 Transmission Overview

The 9HP48 transmission is a 9-speed automatic transmission that was designed and built by a German auto parts company called ZF Friedrichshafen AG. It can be found in a number of vehicles from the Acura MDX and Honda CRV, to the Jeep Cherokee and Land Rover Discovery Sport. The ZF9HP48 transmission is a transaxle type 9 speed transmission which combines the drive axle and gearbox into a single unit. This is ideal for front-wheel-drive based crossover utility vehicles / CUVs that have transversely mounted engines. An AWD transfer case can be connected to the ZF 9HP48 transmission, and it is engine stop/start compatible.

The ZF 9HP48 transmission uses four planetary gear sets (two of which are situated on top of each other), six multi-disk clutch packs, and two dog clutches. Hydraulic control of the dog clutches (and everything else) is achieved with an axially parallel vane cell pump, which itself is designed to reduce drag and increase efficiency. Because of the dog clutch arrangement (dog clutches are essentially two toothed gears that have to be spinning at the same speed in order to lock together), the 4-5 shift and

7-8 shift (both up and down) may feel unnatural because the engine RPM’s have to briefly drop (like you just shifted into neutral) in order to facilitate the dog clutch engagement. Each car manufacturer is responsible for creating the software that controls these shifts, so the feeling that you get when driving a Honda Pilot 9 speed transmission can be completely different from a Jeep Renegade 9 speed transmission.

ZF 9HP48 Applications

ZF 9HP48 Diagnostic Trouble Codes | DTC

ZF 9HP48 Transmission Problems

ZF 9HP48 Transmission Software Updates

Because the ZF 9HP48 9 speed transmission is sold to automakers as a ‘kit’ or manufactured under license, it’s the responsibility of each car company to create the software for the 9HP48 transmission control unit that will govern how it behaves. ZF works with the car companies to help them develop the appropriate programming, however not everybody got it right. Particularly Fiat-Chrysler / FCA and Honda. Since its introduction in the 2014 Jeep Cherokee, it has been known to be plagued with a number of problems that have prompted several recalls, along with a number of TSB software updates and warranty replacements. Some of the known symptoms include:

Lunging forward after an expected downshift
Failure to downshift when accelerating
9HP48 transmission unexpectedly shifts into neutral
Erratic upshifts/downshifts
Failure to shift into 8th or 9th gear
Unintentional rollaway due to the driver possibly selecting neutral instead of park

Some of the vehicles known to suffer from the above ZF9HP48 transmission problems include:

2014> Jeep Cherokee
2015> Jeep Renegade
Ram ProMaster City
2015> Chrysler 200
2016> Fiat 500X
Acura TLX
2015> Honda Pilot
2014> Land Rover Evoque
2015> Land Rover Discovery Sport

ZF 9HP48 Transmission Recalls

– Recall ID – NHTSA: 16V529000 – ZF 9 Speed Automatic Transmission

— Summary
In August 2016, Fiat Chrysler / FCA and German transmission supplier ZF Friedrichshafen AG, recalled 329,540 Chrysler Group vehicles equipped with the ZF 9HP48 transmission. These vehicles include:

2014-2015 Jeep Cherokee
2015 Jeep Renegade
2015 Ram ProMaster City
2015 Chrysler 200
2016 Fiat 500X

— Consequence
According to the recall, there may be insufficient crimps and the transmission wiring harness, which powers the transmission sensor clusters. As a result, the transmission could unexpectedly shift into neutral, which could lead to a crash.

— Remedy
Dealers were instructed to reprogram the powertrain control module and the transmission control module. If necessary, they would have also replaced the transmission range sensor wiring harness. For more information, owners may contact Chrysler customer service at 1-800-853-1403 (refer to the Chrysler / ZF Transmission recall S55) or the National Highway Traffic Safety Administration at 1-888-327-4236

9HP48 Technical Service Bulletins | TSBs

TSB 08-054-18 REV A – Replacement of the PRNDM bezel and harness – 948HP transmission
2015/ – 2018 Jeep Cherokee KL
Problem – Drivers may notice a “service shifter” warning message in the instrument cluster, along with U1465 and P1C86 DTC stored in the ECU memory.
Solution – The PRNDM bezel/display and wiring harness will need to be replaced.

9HP48 Transmission Specs

General – 9-speed automatic
Application – FWD/AWD
Variations – 9HP48X, 9HP48XO, 948TE
Weight – 189 lbs +/-
Fluid Type – ZF Lifeguard 8

Need a replacement transmission? Get an estimate for replacement transmissions and local installation. Look up your transmission model by vehicle make and model.

What Transmission Do I Have?

9HP48 Transmission Gear Ratios

First – 4.71
Second – 2.84
Third – 1.90
Fourth – 1.38
Fifth – 1.00
Sixth – 0.80
Seventh – 0.69
Eighth – 0.58
Ninth – 0.48
Reverse – 3.80