How to Upgrade 4WD IFs System

 If you are a recreational driver or are just setting up a touring ute, this is probably the best approach to take. Simply choose an aftermarket suspension kit from the many available on the market place. The price range is fairly wide and as always, you get what you pay for. With these kits, you will receive a set of front struts and coils, rear shocks and leaves and maybe some greasable shackles. Tough Dog manufacture adjustable struts and rear shocks that are compatible with the Rancho in cab adjustment system. Whilst at the upper end of the price range for this style of suspension, there are well regarded by anybody that has tried them. (that includes the author!) When selecting front coils, it is important to ensure the right springs are selected given the front accessories fitted to your ute so discuss that for your such as dual batteries, bull bars and winch so discuss this with your supplier to ensure you get the right spring.

Born out of the American desert racing scene, these generally include a heavy duty front strut that will provide is adjustable lift from 0 – 100 mm simply by turning a big nut on the outer strut column with a spanner supplied with the strut. The struts may include external reservoirs to allow much more oil to be used than standard struts to aid in keeping things nice and cool at high speed. They are usually fully rebuildable and support adjustable valving to tailor suspension characteristics to your requirements. Unlike the Tough Dogs though, specialist equipment is required to adjust and refill the strut with nitrogen. If you do go this way, make sure your supplier has the necessary equipment to adjust them to suit your application. These kits may also be supplied with aftermarket upper control arms, swaybar drop brackets and diff drop brackets.

 Probably the most expensive suspension lift options are the ones that add cross members and brackets to achieve big lifts (100mm or more). These usually seek to move the front diff lower to keep the CV’s within safe operating limits and replace the upper and lower control arms and possibly even the steering knuckle with one with an extended spindle. The Ultimate Suspension have some great options in this style of kit and taking the time to watch the videos on their web site of standard and modified vehicles is impressive. In most states, engineering approval is required. Ultimate includes replacement brackets to lower the front diff. Other similar kits are available from other vendors. One of the issues with this style of kit is that additional cross members are required under the vehicle and these can eat into off road clearances but they certainly do look the part!

The other easy option that is done to drop the front diff is to add a spacer on the front diff brackets and lower the front of the diff by 25mm. Kits to do this are available from Cal Offroad and Snake Racing. However, because of the distance from the CV shafts, the CV’s are only dropped a much smaller amount, often only about 10mm.  There are differing opinions whether it is worth sacrificing 25mm of under diff clearance for a 10mm improvement in CV position. Some say it is a great idea, others say that you are better off reducing your suspension lift slightly and retain the under diff clearance.

 There are two things to watch out for with your CV’s and driveshafts when lifting your IFS ute. The first is the drive shaft angle as the CV could disengage or break off road and whether the CV boot ribs are rubbing together or not. Many of today’s IFS vehicles no longer have freewheeling hubs fitted which means the drive shafts rotate 100% of the time while driving. If the CV boot fins are pressed up against each other under these conditions, the boots will wear out and split prematurely.

 There are few CV upgrades available on the Australian market. Monster Rides is should have a competition style CV kit for the Hilux 150 which uses stronger steel and a 1.5mm larger diameter than the factory shafts available when you are reading this. They will incorporate an extra 15 degrees of flex which will accommodate an extra 100mm of down travel if the suspension permits this. To obtain this additional articulation, an advanced bracketometry approach will be required and it is their plan to also develop these additional components with a view to also relocate the front diff forwards so that 33″ tyres can be easily fitted without trimming the body mounts.