Occasionally, while testing the limits of our cherished 4WD vehicles, unforeseen mishaps occur. Whether it’s daring an arduous incline with challenging obstacles or enjoying a rugged rock-crawling excursion with friends, there are moments where a final bold attempt is made. And then, amid the fervor of giving it the ultimate push, a resounding metallic snap reverberates—followed by a deafening BANG! The drive shaft shears off cleanly at the yoke. Now, stranded in the remote mountains on a 4×4 trail with mechanical aid miles away, the immediate concern is, can I drive my 4WD truck without the front driveshaft to get the vehicle home for repairs?
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Can I Drive My 4WD Truck Without The Front Driveshaft: REAR ONLY
In emergencies driving a 4WD in rear-wheel drive mode doesn’t pose risks like axle binding or gear shredding on dry ground. If the front driveshaft is removed due to damage and the center differential can be locked, there’s no differential action difference between the front and rear, eliminating binding risks.
Although certain differential components may experience slightly more load, safe driving without excessive speed ensures security. Utilizing 2WD rear wheels allows reaching help promptly after removing the damaged driveshaft—an advantageous aspect of basic traditional 4WD vehicles.
Can an AWD Function Without a Front or Rear Drive Shaft?
Most traditional AWD systems cannot deactivate a driveshaft, unlike 4WD setups. If you’re driving an AWD with an open center differential that can’t be locked and incorporates traction control, this maneuver won’t be feasible. AWDs don’t offer the option to operate solely in front-wheel drive or rear-wheel drive mode.
Also, depending on your vehicle model and if the rear driveshaft utilizes a “wet slip yoke” to connect to the transfer case, attempting to remove this component while driving could lead to oil leakage from the transfer box, potentially causing it to seize up.
Can You Drive A Truck Without A Transfer Case?
If you are driving a 4WD vehicle then all the power is sent to the drive shafts to the differentials through the transfer case. Without a transfer case, you will not be able to drive the vehicle since the power is split 50/50 to the front and rear drive shafts and in 4WD or 4H mode. Alternatively, 100% of the vehicle power is transferred to the rear drive shaft and differential from the transfer case when 2H mode is selected. Hence, without a transfer case, a traditional 4WD vehicle cannot drive.
Driving an AWD without a Rear Drive Shaft
This is not always possible since AWD does not function the same as a FWD – READ more about AWD vs 4WD here. It also depends on your AWD transfer case, however, you cannot disable an axle on an AWD vehicle. If you disconnect the drive shaft to the rear axle the car will not move. That is because the center diff cannot transfer 100% of the power to the front drive shaft, so it will move until the viscous coupling loses all ability to resist shear. This will happen in a matter of seconds.
Also, if you remove the rear or front drive shaft from the transfer case you will lose the transfer case oil. If you do get the vehicle to drive, depending on what AWD setup you have, you might also experience violent vibrations coming from your drive train after a certain speed since the system is not balanced anymore.
AWD and permanent 4WD vehicles make use of a Viscous Coupling. This component does have the ability to not lock up. The function of the viscous coupling is to allow speed differences between the front and the rear drive shafts from the center differential, not as a coupling to transfer power to the rear.
If we use a Subaru AWD Manual transmission as an example, the drive shaft is directly connected to the center diff. Power has to go through it to get to the front or rear wheels. If the viscous coupling gets damaged the center differential is open. This means it won’t transfer any power to the front if the rear wheels aren’t connected.
Driving a 4WD with the center differential locked and the front or rear driveshaft removed will get you to safety without much drama. Provided the transfer case doesn’t use a type of viscous coupling between the front and rear as in the case of a permanent 4WD and AWD. This component could heat up to damaging temperatures when there is a speed difference between the two. This means your transfer case will effectively destroy itself.
Or the vehicle just won’t move forward in the case of an AWD since there is no way of locking the center diff.
The bottom line is, to have the vehicle fixed as soon as possible. These 4WD and AWD systems are highly engineered and designed to function in a very specific manner that allows power to be transferred equally and safely to the drive shaft without damage. Do not attempt to continue driving a 4WD with the center differential locked for longer than necessary. Look after your 4WD and it will look after you!