Why Jeep Wrangler 4 Wheel Drive Not Engaging? (Fix Now)

The 4-wheel drive system in your Jeep Wrangler was invented to help slick and crawling roads to get more control. But the situations on the rough roads can be very frustrating when your Jeep Wrangler needs to engage in a 4-wheel drive.

The 4-wheel drive on your Jeep Wrangler can be unable to engage for several reasons. But actuator problems, malfunctioning switches, damaged vacuum pipes, or due to missing linkages are the most prevalent.

When the 4-wheel drive is not working, the jeep Wrangler will not give you enough support on tricky roads. Go through this blog to understand why Jeep Wrangler 4-wheel drive is not engaging, some possible reasons behind this, and the solutions to this problem!

Why Jeep Wrangler 4 Wheel Drive Not Engaging And How To Fix 

There are many reasons why your Jeep’s 4WD system may fail to engage. The indications will be very similar across all of them; for example, the 4WD light may flicker on the dash but never engage, or the 4WD light may beam solidly, but there is no active 4WD engaged. 

Let’s discuss some common scenarios:

01- Faulty Switch

The switch we are talking about here is the vacuum switch located on the transfer case. The vacuum hoses directly connect to the four nipples on the switch. Any malfunctioning internal can stop your Jeep Wrangler from engaging to 4-wheel drive.

To troubleshoot the problem, unscrew the vacuum switch from the TC and check for faults. If it has jammed balls in the bearing, fix this, or you can consider buying a new one! Reinstall the parts and test your Jeep Wrangler. If the issue still needs to be resolved, consider the following reason.

02- Failed Actuator

The actuator in your JEEP Wrangler helps your car to engage the 4-wheel drive. It can work via an electric signal or air vacuum. So, any problem with the actuator, like a faulty actuator motor, damaged gears, or faulty actuator electric module, will cause the 4-wheel drive not to engage.

You need to take your car to the mechanic or an expert to troubleshoot the problem. They will fix the malfunctioning unit or replace the whole actuator if necessary. If you have enough knowledge about this, you can do it in your garage too!

03- Damaged Vacuum Pipe 

When the whole vacuum system is working, but the vacuum pressure is not enough to reach the front axle shift motor, your 4-wheel driving system will not engage. You can use a flexible pipe to check if there is any vacuum leak in your Jeep wrangler when you try to engage a 4-wheel drive.

When you notice vacuum leakage on your Jeep Wrangler, simply install the 4×4 Posi-Lock system. The directions are straightforward, and it’s a do-it-yourself project that requires only a few basic tools. You’ll never have to worry about your 4WD not engaging again with the 4×4 Posi-Lock system.

04- Missing Or Loose Linkage

The linkage in issue is the one that links the transfer case shifter lever to the transfer case’s actual selector arm. This enables the driver to activate 4-wheel drive mode and select 4-Lo. If the lever is looser than usual, or if you shift the lever back, the Jeep Wrangler fails to enter 4H or 4Lo.

Whenever it occurs, you must examine it quickly by getting beneath the Jeep Wrangler and inspecting the transfer case linkage. It’s a pretty cheap part that you can find online. It’s referred to as a linkage adjuster. This simple fix can solve your problem quickly.

Read Also: How to Put Jeep Wrangler In 4 Wheel Drive? (4H & 4L)

Tips to properly Put Your Jeep Wrangler in 4 Wheel Drive

If you understand how the new part-time 4-wheel drive system works and how to change the gears properly, you will do less damage to your car and face fewer issues with the 4-wheel drive-related problems. 

Shifting Between 2- Hi to 4- Hi

When you want to switch from 2- Hi to 4-Hi, keep your driving speed around 35 mph or 56 km/h. After reaching 4-Hi, you need to maintain a speed of around 15-55 mph or 24-88 km/h. 

Remember to press the clutch if your Jeep wrangler has a manual transmission. You can change gears when the vehicle is stopped, but it’s not recommended because the teeth may not align properly in that case.

Shifting Between 4- Hi to 4- Lo

Shifting from 4-Hi to 4-Lo involves slowing your Jeep Wrangler down to 2-3 mph (3-5 km/h). It would be best if you shifted the transmission lever into neutral and the gear selection into D or depressed the clutch pedal and released it.

After that, firmly push the transfer case lever from 4-Hi to 4-Lo without halting at neutral. Maintain a speed of 25 mph or 40 km/h, and carry on!

Shifting Between 2- Hi to 4- Lo

This transition is a bit tricky, as a wrong move can damage your Jeep Wrangler. When you are on 2- Hi, and you want to move to 4-Lo, you need to move to 4-Hi first and then neutral. After that, you can safely shift to 4-Lo. The process is the same when you shift back to 2-Hi from 4-Lo.

Read Also: What Does Service 4WD Light Mean In Jeep? [Explained]

FAQs

We expect that the above parts were helpful for you, but if you have doubts, go through this section to get answers to some frequently asked questions!

Is It Ok To Drive A Jeep Wrangler In 4WD All The Time?

According to Car and Driver,  the Jeep Wrangler 4WD is intended to be utilized only some of the time. It is only for particular sorts of roads, such as challenging terrain and off-roading, and slippery situations, such as snow or mud. 

Conclusion

Having a 4-wheel drive system is a great advantage for an off-reading car like the jeep Wrangler. But the convenience goes in vain if the feature is inaccessible or the 4-wheel drive is not engaging. So when you see indications that your Jeep Wrangler 4-wheel drive is not working, you need to fix that issue as soon as possible.

A faulty 4-wheel drive will give you less confidence on challenging roads and can cause a significant problem for you. So we recommend you drive carefully and follow the rules of changing gears so that you face these problems less. Maintain your vehicle properly and keep off-roading with Jeep Wrangler!