4WD Diff Drop – Why You Need It

When it comes to lifting your IFS (Independent Front Suspension) 4WD at some point you will come across a diff drop. When lifting your IFS 4WD you need to take into account the angles of your CVs. Generally anything higher than 2” you will need to drop the diff. With the new maximum droop point changed there is potential to break a CV from overextending and putting the joint on an angle where it cannot handle the load.

Toyota Fortuner 4wd diff drop suspension flex. Aberdare State Forest

What is a diff drop?

A diff drop is a bracket or a spacer that moves the diff housing down.

What does a diff drop do?

A diff drop lowers the diff so that your CVs are in better alignment. They will give some correction in the CV angles from lifting the front of your 4WD.

Why do you need a diff drop?

A diff drop will reduce the chances of breaking a CV. If you have lifted your IFS 4WD 3”, 4” or more you should consider dropping the diff.

How much drop? 

When it comes to the Roadsafe diff drop that we installed, they are a 1” spacer for the front of the diff brackets. With the diff being mounted in the middle of these brackets it will lower the diff by ½”. There are other complete diff relocation kits that will lower your diff by 30mm but there are a few other things you’ll need to take into account, like CV boot clearance.

How hard is fitting?

It is really simple and can be done with basic hand tools.

  • Remove the bash plate.
  • Undo the front two diff bolts.
  • Insert the spacers and insert the new longer bolts. We did have to trim one side as it was a little long.
  • Put the spacers between the bash plates and reinstall. That’s it.

Toyota Fortuner Roadsafe diff drop spacers

Why did we choose the Roadsafe diff drop?

It was never the original plan. When I came across the Roadsafe diff drop on Auto Parts Co for just over $100, I thought why not. It might be the ½” that saves us from breaking a CV off road.

With the new UCA’s installed we have clearance around the strut. The ball joint angle has been put in better alignment and with the diff drop now in we will be looking at longer shock options to get more down travel in the front. The more down travel will keep the wheels on the ground longer and us moving through the tough stuff.


As part of our Fortuner suspension project we also changed:

HGT was gifted 4wd diff drop. All opinions are our own.

Get Social
Latest posts by Happy Go Travel (see all)

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.