Castor correction advice please

[MudRunnerTD]

just an update, Tyrepower do have the specs from the original alignment (front and rear) and will re-check them next Tuesday morning. He did explain that yes the only way to correct the issue may be the castor kit as he checked the tyres and said there is no extra wear that bad now that would cause the tramming to be that bad. He did advise to get the correction kit from ARB or Opposite Lock here in town and not to go to the local Ironman centre though. So will post back here on Monday. Thanks for the help thus far people :-)

It will just be bushes mate, I'd go ARB if i had to fit them. You will pay a premium for ARB to fit them but supply only they will be fine. get a couple of quotes to fit them if you supply them. that is where the money is. Any workshop with a 20T workshop press should be able to do the job.

[timbo2410]

yeah the Tyrepower chap explained that there is no way to correct castor issue without either bushes or new radial arm .. as explained here (so I don't think he was trying to BS me). He also went on to say (after I explained I had the lift kit done by Ironman franchise), that he himself would go to ARB and get the kit .. he wasn't really happy that I was sold a non centering damper either .. ??

[timbo2410]

yeah the Tyrepower chap explained that there is no way to correct castor issue without either bushes or new radial arm .. as explained here (so I don't think he was trying to BS me). He also went on to say (after I explained I had the lift kit done by Ironman franchise), that he himself would go to ARB and get the kit .. he wasn't really happy that I was sold a non centering damper either .. ??

[MudRunnerTD]

Im not a big fan of Return to Centre Steering (RTC) dampeners. Not really required on a 2" lift running 33s. The geometry should be perfect and the car should track straight. end of story. I dont have a RTC dampener on either of my cars. My GQ runs a 5" lift and 37s with No RTC Dampener.

[Bidja]

GU caster tolerance +/-1 deg from memory. Rule of thumb 1 deg caster correction per 1" of lift. U may not need them. Mine 2" lift bought 2 deg polyurethane caster correction bushes ($100 ebay specials), 90,000 ks ago still good. Do not go hard core off road but do my share of tracks and corrugations for sure (my dirt road to gate would sort them). Maybe just get a good whl alignment first up just to see results & go from there.

U could buy bushes (have in hand), go to good steering & suspension SME to check current geometry and fit bushes if req'd for 2"lift.

Local Koni distributor / alignment shop charge me $270 / 5 yrs ago for alignment($65) + fitting of bushes ($205). A bit of cost escalation expected for sure + $100 purchase for bushes.

Also, would not go RTC dampener, good HD do the job well.

[timbo2410]

hopefully the readings on Tuesday will give me a better idea as to what is going on .. I will post the results for everybody to look at and comment on. I did notice today that the tramming was slightly better after the service .. this didn't make sense as he didn't actually do anything. Then I took a tyre pressure reading and they have been pumped up to 42psi .. the tramming is still there and it is still very light at the front .. but it is slightly better.

[MudRunnerTD]

hopefully the readings on Tuesday will give me a better idea as to what is going on .. I will post the results for everybody to look at and comment on. I did notice today that the tramming was slightly better after the service .. this didn't make sense as he didn't actually do anything. Then I took a tyre pressure reading and they have been pumped up to 42psi .. the tramming is still there and it is still very light at the front .. but it is slightly better.

Try dropping the tyre pressure only in the rears to 35psi and go for a drive. 30psi even. This should fix it short term.

[timbo2410]

Nissan had them at the 30 front and 29 rear after their service .. was all over the road at 80kph .. I usually run them at around 37/38 psi .. but the 42 psi certainly helped the tramming today.

[MudRunnerTD]

Nissan had them at the 30 front and 29 rear after their service .. was all over the road at 80kph .. I usually run them at around 37/38 psi .. but the 42 psi certainly helped the tramming today.

Just to experiment. Drop the fronts to 30psi. This will change the caster by a couple of degrees and the problem should reduce again or go away.

[timbo2410]

Wouldnt dropping the front increase the castor error? If the effect of raising the suspension causes the front axle to be drawn further back (tilting it under the car) then wouldn't it be that the rear tyres needed to be lowered to have any effect on the castor? Or is it that regardless of the incline or decline the castor is out and raising or lowering the front or back will not effect the castor itself? Just trying to wrap my head around it is all :-)