a mechanism that makes possible an increase in the tractive force of a motor vehicle by increasing the gear ratio of the transmission. For example, an auxiliary gearbox is used in the transmission mechanism of heavy-duty motor vehicles and tractors to increase mobility under heavy road conditions.

How does auxiliary transmission work?

This auxiliary transmission contains two sets of gears, thus giving the reduction (low) ratio when power is delivered through these two sets of gears. The other speed is obtained by direct (high) drive through the auxiliary.

What is an auxiliary transmission?

The auxiliary transmission has a high speed transmission line equipped with a hydraulic clutch and a low speed transmission line equipped with a one-way clutch for allowing the overrun of the output side of the low speed transmission line so that the low speed transmission line is established when the hydraulic clutch ...

Can you switch from 2H to 4H while driving?

The best part of it all is, you can switch 4WD modes between 2H and 4H and while driving without any risks of speeds below 60mph/100km/h. You could drive it in 2H with only the rear wheels propelling the vehicle forward or when traction gets a bit “iffy” you just pop it into 4H – no problem at all.

Can I shift into 4WD while moving?

Don't try to engage these 4 wheel drive systems when the vehicle is moving or you can damage expensive components. However, most 4WD systems can now be shifted into or out of 4WD on the fly at the push of a button. ... They shift into and out of 4WD automatically as the system detects the need for more traction.

How to use 4WD gears & when to use them.

What is 4H 4L N & 2H?

Four-wheel drive vehicles generally have three settings: 2H, 4L, and 4H. 2H is ideal for normal, everyday driving. Use 2H for dry, flat, paved roads. 4L is best suited for a time when you need maximum traction and power. ... 4H is your go-to setting for driving at normal speeds (30 to 50 MPH), but with additional traction.

What is 4WD neutral for?

Neutral — This range disengages both the front and rear driveshafts from the powertrain. To be used for flat towing behind another vehicle. ... Driving in the 4WD LOCK and 4WD LOW positions on dry hard surfaced roads may cause increased tire wear and damage to the driveline components.

What is a 2 speed Autotrac transfer case?

The available Autotrac system (RPO NQH) is a 2-speed automatic, active transfer case. The system provides five modes: Auto 4WD, 4HI, 4LO, 2HI and Neutral. ... The software calibrations allow for vehicle speed dependent clutch torque levels to enhance the performance of the system.

What is an auxiliary transmission used for?

The auxiliary transmission (fig. 4-21) is used to provide additional gear ratios in the power train. This transmission is installed behind the main transmission and power flows directly to it from the main transmission, when of the integral type, or by a short propeller shaft (jack shaft) and universal joints.

What is TTC in auxiliary?

Transmission Technologies Corporation (TTC) manufactures six models, including two pneumatic (air-shifted), and four manually shifted units. ... Providing maximum flexibility, all SPICER brand auxiliary transmissions have four speeds, with a . 81 overdrive ratio.

How do 2 speed rear ends work?

The 2-speed axle works on the same basic principles, but with an added planetary gear set inside the ring gear. ... This works by sliding a clutch gear meshing with the high range clutch plate. When the low range is selected, the sliding clutch gear engages with the low range clutch plate.

What is a multi speed rear axle?

On many vehicles, multi-speed rear axles and auxiliary transmissions are used to provide extra gears. They are usually controlled by a selector knob on the gearshift lever.

What is an auxiliary transmission cooler?

An auxiliary cooler will keep your transmission running right where it needs to be, ensuring you don't overheat your transmission. Driving Conditions - If you live somewhere that gets excessively hot or is fairly hilly or mountainous, an auxiliary transmission cooler is a good option for you.

What is a Meritor transmission?

ZF Meritor Launches Fully-Automated Heavy Truck Mechanical Transmission. ... It eliminates manual clutch actuation for start and stop, and gives drivers the option of fully automated or operator-controlled shifting. The new line of transmissions will benefit fleets through increased fuel economy.

Can you drive a 4x4 without 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. ... Hence, without a transfer case, a traditional 4WD vehicle cannot drive.

How do you engage manual 4WD?

You engage 4WD in a manual transmission Jeep by depressing the clutch and shifting the 4WD gear shifter into 4H. Always ensure you are not accelerating while doing so and give the 4WD shifter a firm yank to ensure it engages fully. When engaging 4L (Low Range) you need to drive as slow as 2-3 MPH.

How fast can you drive in 4 wheel drive high?

It is not recommended to drive faster than 55MPH in 4WD high on low traction surfaces. 4WD should only be engaged when road surface traction is low. Driving in 4WD-Lo should not exceed 10mph.

Can I use 4H in rain?

Does 4 wheel drive help in the rain? Yes, 4 wheel drive offers improved traction and handling in slippery driving conditions such as mud, ice, snow and rainy weather. Since all 4 wheels are moving the 4wd forward, the vehicle will feel more sure-footed and stable on slippery slick and greasy surfaces.

Can you reverse in 4X4?

You can reverse in 4-wheel drive without risk provided you are driving on a low-traction surface. Driving forward while in 4WD is the same as reversing and the functionality inside the transmission and Transfer Case works the same in reverse.

Whats 4H stand for?

Head, Heart, Hands and Health

Head, Heart, Hands, and Health are the four Hs in 4‑H, and they are the four values members work on through fun and engaging programs. The pledge is available in English and Spanish.

What happens if you switch to 4WD while driving?

If you are driving on clear, level roads, you should not be using 4WD. Because these roads provide their own traction, using 4WD can lead to drivetrain binding and can ruin your vehicle. No matter what vehicle you drive, never shift to 4WD when traveling at high speeds or when on dry, level roads.

Is it safe to drive in 4WD on the highway?

The short answer is: Yes, it can be safe to drive in 4WD on the highway as long as you're going very slowly and so does the rest of the traffic around you. In other words, only during severe road conditions that require you to.

How often should you engage 4WD?

In general, you should do this once a month if you don't take your truck off-road or if you live in an area without snow.