There are two common types of handbrake systems fitted to 4wd vehicles:
- A handbrake which works on the rear brake shoes.
- A transmission brake that is fitted to the rear output of the transfer box.
Being aware of what type of handbrake you have on your 4wd is important when using it in a harsh environment.
The more “off-road capable” 4wd vehicles tend to have a transmission hand brake as this gives braking on all four wheels when 4wd is selected or the centre differential is locked.
Also, a transmission brake has more ground clearance; therefore, when travelling through relatively deep mud is less likely to get contaminated and fail.
Update: Enter the Electronic Handbrake!
I don’t know what was wrong with the old cable types but forever onwards goes the need to put electronics in vehicles. Things electric generally don’t like mud and water. Beware of the depth of stuff and whether it’s a transmission or rear wheel type.
I’ve known both to get locked up or fail to work after doing off road work.
Obviously the vehicle manufacturers are aware of this and I do believe they are working on reliability.