Guitar truss rod is a critical metal part to correct and protect the neck from deformation. 

To select right one, we need to know the types, to inspect the difference and to have an idea about the advantages and disadvantages. After this, we will also talk about the length of the rod to get the idea which length fits your project the most. 

In the end, there are some tips to help you to select the most proper rod for your own guitar necks.

If you want to purchase, visit GUITAR TRUSS RODS to select right types.


It is normally considered that there are two types of truss rod: single action and dual action. Both of the two types have their own advantages and disadvantages. However, it is better let’s have a look about the difference between them.

Single action, Definition & Properties

Generally, the single action type (also known as one-way truss rod) is designed to correct the guitar neck against the pulling tension caused by strings. 

The name “single action / one-way” comes from the rod moves in one direction to correct forward-bowing of the neck.  The correction is by the tightening or loosening the truss rod screw. Since this type can only move in one-direction, the truss rod cannot bend back on itself, thus additional relief cannot be created. 

single action guitar truss rod

This single way type is only threaded on one side while opposing side is fixed without any adjustability.  The rod is designed to be fitted in a channel with variable depth routed from the back of the neck.

The advantage of this type is that it removes less wood of the neck. The main disadvantage is that this guitar truss rod cannot correct an already back bowed neck.

Advantages of dual action

A dual action rod, also known as two-way truss rod, is commonly seen on modern guitars.  Mainly because one of its advantages is to have full control of the angle of the neck conveniently. 

The rod is able to adjust the relief of the neck backwards and forwards. This tells another advantage of two-way guitar truss rod: stable and less influenced by changes in the climate.

dual action guitar truss rod

This type of truss rod is threaded on both sides, one end will have a left thread and the remaining has a right thread, with a fixed metal bar alongside the length. Further, both of the ends are fitted with nuts. Thus, it is easily bent to create a back bow and forward bow. 

Well, it is also said that the dual action truss rod will negatively affect the tone.  This may because of the heavier weight of the rod. And to install the truss rod, requires to remove more wood which may slightly alter the tone of the instrument. This is also normally recognized as a main disadvantage of this type of guitar truss rod.  

The third type, none-adjustable

None-adjustable rod refers to the one that is not able to temper and customize the tension of the neck.

This type is not frequently seen nowadays. But still can be found on low-end beginner type of guitar on a very cheap scale.


Guitar truss rod comes in different lengths mainly according to the length of scale. 

Normally, 18” for guitars and 24” for basses are the standard measurement. But in fact, the length measurement can be various like 375mm ( around 14.7”) and 380mm (around 15”).

Therefore, it is better to confirm your scale length before buying any types of truss rod. 

Always keep in mind that wrong length of truss rod won’t work.


Above all, we can figure out some tips to help you to choose right guitar truss rod for your own project.

1. Since we have discussed about the different properties between different types of guitar truss rod, you may choose according to which properties are the key to your project.

2. Knowing which adjustment you need is another key to choose the right rod.

3. It may necessary to know what level of the guitar you building before to choose any parts for building. If you are building low-end guitar for beginners, then any truss rod cost that hurts your budget won’t be a good choice.

4. Unless the scale length is fixed or there is no changes of your guitar building project, it is better to measure the length of your scale before buying.

5. The most important is to choose reliable and responsible supplier to support you.


    Visit  TRUSS ROD PRICE for more info about our pricing & shipping.

    To understand our quality, it is recommended to check GUITAR NECK TRUSS ROD PROPERTIES.