How important is caster in an IFS

[Jkspinner Junior Member Find all posts View Profile Close Jkspinner]

Hi all
I have recently installed a 2" lift in my 150. Looking at the wheel alignment specs, it tells me the factory caster should be 2.45deg +- .45deg. My height is about 795 - 800mm. After the lift, I have only .43 deg on the right and 1.25 deg on the left.
I came from a live axle Jeep where caster is so important and low caster lead to all sorts of front end issues.
So how important is caster in a an IFS vehicle. Looking at other posts, I see that most people have similar specs after a lift.
Should we all be looking at upper arms. If cost was not an factor, should we be looking at UCA's, or it doesn't really matter.
Be great for some of the vendors to chime in here.

[Guest Close Guest]

Less caster will result in lighter steering and the steering wheel will not self-centre so easily. Lots of lifted Prados don't run aftermarket UCAs as it's not a big problem.

[Jaymboze Member Find all posts View Profile Close Jaymboze]

I installed adjustable upper control arms as I could not get any more camber adjustment from the factory ones.
Once installed, I could get the wheel alignment back to correct specs.
Without them it had positive camber which not only looked bad but did not steer very well.
One of the best things I've fitted to the car.

[mackayvx Advanced Member Find all posts View Profile Close mackayvx]

I found with our rig that the more castor it had the better it held the road.
In fact it steers straight as a die with a big lift and tyres.
Cant remember which side to max out, but max the required side out and have 1 degree less on the other.
That is with standard UCA & LCA's.
It took a lot of research and many wheel alignments to work that out, as most wheel aligners know SFA about wheel alignment.

[wholesalesuspension Advanced Member Find all posts View Profile Close wholesalesuspension]

Mackayvx has it.
Castor is an often forgotten part when doing a lift.
The IFS vehicles don't suffer as bad as the Jeep would have or a Patrol or Cruiser for that matter also, because on the IFS vehicles when you lift them, the lower arm just pivots down further.
With cars like the Jeep, Patrol etc mentioned, the front control arms effectively become shorter as you raise the vehicle and the front wheels come back closer to the driver. Castor correction is a hugely important and often overlooked part of a lift on these.

Regards, Jason.

[Whitey1 Advanced Member Find all posts View Profile Close Whitey1]

I used to do wheel alignments as part of my job, you generally need between 0.5 and 1° more castor on the left to counter the slope of most roads. If both sides are the same the vehicle will usually pull or drift to the left.
Now that's just a broad generalization and varies from car to car, but as others have said, more castor means straighter driving and less means twitchy steering.