answersLogoWhite

0


Best Answer

Most semi tractors with three axles are a 6x4 configuration, also referred to as 'twin screw'. On these, power is transmitted from the engine to a power divider, which is basically a differential. The power divider has outputs going to both drive axles, and supplies power to both drive axles constantly. Many drivers think a power divider lock engages one of the axles, but this is incorrect - power in constantly provided to both axles, and the PDL simply locks the outputs to rotate at the same speed to both axles (when unlocked, the power divider can account for differences in tire height at each axle). Some three axle tractors have only one live axle, but this is a bit rare in North America. In Europe, where 4x2 was the norm, and you could put 40,000 lbs. on the single drive axle, some have added an additional lift axle to reduce damage to roadways, but this axle is not powered.

User Avatar

Wiki User

13y ago
This answer is:
User Avatar

Add your answer:

Earn +20 pts
Q: What drive axle pulls constant on a semi truck?
Write your answer...
Submit
Still have questions?
magnify glass
imp
Related questions

What does the second drive axle do in a tandem drive truck?

The exact same thing as the first drive axle.


What is the first second and third axle of a semi truck?

#1 axle is the steer axle, #2 axle is the front drive axle, #3 axle is the rear drive axle.


How do you mesure your wheelbase on a semi truck?

From the center of steer axle to center of rear axle on trailer. If you want just the truck it's the center of steer axle to center of rear drive axle.


How much is the toll on the verrazano bridge for 1 axle truck?

There's no such thing as a one axle truck. There has to be a minimum of two axles. "Single axle" if a term referring to a truck with only a single drive axle, and doesn't count the steer axle. Same with "tandem axle", "tri axle", "quad axle", and "quint axle".


What is single axles semi truck?

The power unit has a steer axle, and only one drive axle.


How to Drive a tri axle dump truck?

Go to a truck driving school. You're not going to learn how to drive a Class 8 truck by reading about it on this website.


What is a tri-axle dump truck?

It's a dump truck with four axles--the steer axle in front and three axles in back. One of them moves up and down via a control in the cab, so the tires aren't on the road if the truck's not loaded. A tri-axle dump truck carries more weight than a one-axle or two-axle truck.


What does wheel base mean for semi trucks?

The length from the middle of the steer wheels to the center point between the drive tandems (for a tandem truck) or center of the single drive axle (on a single axle truck).


What is a single-axle truck?

Those designations actually exclude the steer axle, and only count axles behind the steer axle, so what you're talking about would actually be a truck with two axles - a steer axle, and a single drive axle.


Does a 1990 Nissan pickup have a front drive shaft and a rear drive shaft?

It depends if it is a 4 wheel drive truck. A rear driveshaft is used to drive the rear axle. A front driveshaft is used to drive the front axle on a 4X4.


How much weight can be on each axle of a single axle straight truck with a gross vehicle weight of 54000 lbs?

20,000 on the steer axle, 34,000 on the drive tandems together.


What axle pulls on tandem trucks?

They both do. With the differentials unlocked and the truck in gear, if you raised just one of those wheels off the ground, all the torque would transfer to that wheel (which would be the path of least resistance), and the truck would be going nowhere.. that wheel would just be spinning in the air. The power divider lock doesn't engage the second axle - the second axle is already engaged. The power divider lock simple ensures that the driveshaft to the rear axle continues to rotate at the same speed at the driveshaft going to to forward drive axle.