The ARB castor correction kit...

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Top of pagePrevious messageNext messageBottom of pageLink to this message   By nadim on Sunday, April 15, 2001 - 06:48 pm: Edit

Hello there...

First off, happy Easter...

I was wondering what this kit consisted of...and what price was it running for?...

If I intend to 'kink' my front radius arms to match the lift..do I still need them?

Thank you very much in advance...

Nadim

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Mike on Sunday, April 15, 2001 - 07:26 pm: Edit

It consists of 4 bushes (I'm guessing from the picture) that give you 2 degrees of offset correction. Head to www.arb.com.au and click on Old Man Emu 4x4 Shocks and Suspension. Scroll to the bottom and click on Spring and Suspesion Bushes. Look for Caster Correction Bush Kits. I think that it sells for less than $60.00 US.

How do you plan to 'kink' your front radius arms?

Thanks,
Mike

Top of pagePrevious messageNext messageBottom of pageLink to this message   By JIM on Sunday, April 15, 2001 - 11:13 pm: Edit

Mike,

What do you need to do to the radius arms? Is that what is giving me the knocking noise under my feet??

Thanks,

Jim

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Bill B on Monday, April 16, 2001 - 03:51 am: Edit

I've got the bushings in my truck - just 4 urethane radius arms bushings with the bolt sleeve cast offset in them (ie: not in center). Work fine for my 2" RTE springs, but wouldn't do much for anything beyond that. The offset radius arms do away with the need for the castor correction bushings.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Discosaurus on Monday, April 16, 2001 - 06:05 am: Edit

> If I intend to 'kink' my front radius arms to
> match the lift..do I still need them

No.

The bend will correct the problem. Be sure you
tell the guy doing the mod how much lift you have
on your truck.

The OME offset bushings are not real rugged. They
will go to hell pretty quick if you off-road a lot
in tough stuff. The modified radius arms are the
way to go if you stick with stock LR front susp.

keith
discosaurus

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Bill Gill (Bluegill) on Monday, April 16, 2001 - 06:47 am: Edit

Bill B: did you do the castor correction bushing job yourself? How did it go if you did do it yourself?

Nadim, Discosaurus: how are you going to custom bend your radius arms?

I have OME HD front and don't have any vibrations, but after new tires (slightly bigger), I have a little wander and light steering feel - especially when braking. Tires are stiffer 10-ply with harder compound and bigger lugs, and I'm still playing with the pressure to find optimal setting, but I'm wondering if castor correction would help my cause (couldn't hurt...).

Top of pagePrevious messageNext messageBottom of pageLink to this message   By nadim on Monday, April 16, 2001 - 07:03 am: Edit

i intend to cut them in half, get a TIG welder, get a guy who welds like magic, and fix them up again, with some more reinforcement...
as you can see, it is stil lin the theoretical stage!
:)

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Bill B on Monday, April 16, 2001 - 07:34 am: Edit

Bill - Sorry, I pussed out and had my friends shop do the bushings - just too much of a PIA job and at the time, I had no press available to push the old out an new ones in. I do know that sometimes the stock rubber bushings have to be burned out and then cut to remove them. So far no problems with the durability with a good bit of off-road. Guess I'll see in the long run. I do have an extra set of radius arms in the basement to send to RTE for offsetting when funds permit.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Bill Gill (Bluegill) on Monday, April 16, 2001 - 07:40 am: Edit

Yeah - bushings are a real PIA - best to have a shop press them out with the right equipment. $60 bushing kit + a little shop time is less than RTE $250 off-set, although the RTE off-set is the best way to go. I'll have to see what I can do...

Thanks.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Slider on Monday, April 16, 2001 - 10:15 am: Edit

If you correct castor with a RTE 2" lift...doesn't this put the Differential more level with the ground --and out of plane with the driveshaft ???

Top of pagePrevious messageNext messageBottom of pageLink to this message   By JEEPETR on Monday, April 16, 2001 - 10:57 am: Edit

Yes, It Does Slider. It actually Aggravates driveline angle issues, but helps to correct the poor handling associated with bigger lifts. Makes you wonder why everyone talks about the bent radius arms as a solution for the drive line vibration, doesn't it?

~Scott T.
'95 D-90 (JEEPETR)
'96 Discovery (New Addition to the Addiction!)

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Bill Gill (Bluegill) on Monday, April 16, 2001 - 11:09 am: Edit

> If you correct castor with a RTE 2" lift...doesn't this put the Differential more level with the ground --and out of plane with the driveshaft ???

> Yes, It Does Slider. It actually Aggravates driveline angle issues, but helps to correct the poor handling associated with bigger lifts.

Now, I'm under the impression that lifting causes driveline vibes due to increased angle of shaft (frame/tranny lifted relative to diff). I've been told that castor correction kit realigns axle/diff/shaft to compensate for lift. If you bend radius arms, isn't it the same net effect? The first I heard of castor correction improving handling was from ARB's website - I've always associated castor angle variation with vibes, not handling.

So, is castor angle correction, either via off-set bushings or bending radius arms, the cure for or cause of driveline vibes? What, if any, effect does castor angle have on handling?

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Bill B on Monday, April 16, 2001 - 11:10 am: Edit

In my case - I had no driveline vibration issues - just shitty handling on the highway - the bushings were the cheapest/quickest way to correct. I've had OME springs with spacers and RTE springs and not had driveline problems with either, but all DIsco's are different.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By JEEPETR on Monday, April 16, 2001 - 11:25 am: Edit

Hey Bill Gill,

Yes and no. Lift does increase the angle of the universal joint at the transfer case, but in a twisted turn of events, actually lessens the angle of the universal joint at the pinion. Watch you axle as it drops out next time your truck goes up on a lift. The axle rotates down and toward the front of the truck as the axle drops out, and this in turn rotates the pinion upward, lessening the angle in the pinion side universal joint. If you correct the castor (either with bushings, or offsetting the arms) you rotate the axle back toward where it was stock, and increase that angle again. Am I making any sense? It is the angle of the universal joint at the transfer case that is generally the culprit for driveline vibrations, and the one that is replaced with a double cardon joint when you buy a "CV" drive shaft.

As for the castor and effect on handling, a lack of castor causes very light steering feel, loss of self centering and wandering problems. It also manifests itself as a hard pull when braking. Castor correction is for Handling purposes, not driveline vibrations....

~Scott T.
'95 D-90 (JEEPETR)
'96 Discovery (New addition to the Addiction!)

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Bill Gill (Bluegill) on Monday, April 16, 2001 - 02:13 pm: Edit

Hey JEEPETR and Bill B.:

(JEEPETR)> As for the castor and effect on handling, a lack of castor causes very light steering feel, loss of self centering and wandering problems. It also manifests itself as a hard pull when braking.

This is EXACTLY what I am experiencing - light feel, no centering, wandering, hard pull when braking. But it didn't become apparent until the new tires, so I attributed the handling probs to the different tire size/construction/tread. Sounds like I need to alter castor angle, but will this cause bad vibes? Bill B., I'd appreciate your input here, too. Sounds like you had no vibes, shitty handling, installed castor correction kit, then good handling and still no vibes??? FYI, I have OME HD front and MD rear shocks and springs and 245/75/16 tires with a net lift of 3" over my sagging stock (about 2-2.5 from OME and 0.5 - 1 from tires).

Thanks,
BlueGill

Top of pagePrevious messageNext messageBottom of pageLink to this message   By nadim on Monday, April 16, 2001 - 02:44 pm: Edit

ok...

so the castor correction kit and the bent radius arms have the same objective...to get back the sturdy feel of a stock disco after lifting it...

but the drawback is that it promotes more dirveline vibration...right?

so what is the best thing to do, given that i have a 3.5" lift, and i do NOT intend to change my driveshaft (since there are none available where my disco is...)????????

thank you in advance...

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Bill B on Tuesday, April 17, 2001 - 01:40 am: Edit

Bill - you hit the nail on the head - I never had, and still do not have and driveline vibration problems. Neither spring setup gave me any troubles there. As soon as I installed my first set of springs (OME), the on-highway wander and especially light steering made it miserable. So, in went the castor bushings and all was well - felt like stock again AND aligned to factory specs. After installing the RTE springs, no adjusments were made to the position of the bushings and still all is well. Hope this helps.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Bill Gill (Bluegill) on Tuesday, April 17, 2001 - 05:42 am: Edit

Thanks, Bill and Scott. You've helped quite a bit - I was ready to chew out the tire shop for messing with my ride (and I was ready to return tires and try another set). I'll be ordering the ARB castor correction bushings today for install this weekend. Nathan, did you get my email? Are you following this string? Please send me a quote!!!

-BlueGill

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Discosaurus on Tuesday, April 17, 2001 - 09:05 am: Edit

> so what is the best thing to do, given that i
> have a 3.5" lift, and i do NOT intend to change
> my driveshaft (since there are none available
> where my disco is...)????????

Grease it a lot ! And, hope it doesn't make too
big a hole in your t-case when you break the u-
joint.

A 3.5" lift IS going to trash your front drive-
shaft eventually.

...sorry

keith
discosaurus

Top of pagePrevious messageNext messageBottom of pageLink to this message   By nadim on Tuesday, April 17, 2001 - 04:00 pm: Edit

ok...after some thought, i have decided on the following:

since i intend to relocate my front axle some 1 & 1/2 inches forward, i'll have to cut and reweld the front radius arms accordingly, with some sort of angle to save both the axle bushings, and the chassis bushings..

this will also correct the castor somewhat, but i will be sacrificing the castor angle for the driveshaft angle...sine the latter is a more serious problem that the first...

i know...i know...then i'll be dealing with 2 unsolved problems...but hey...i'll be favoring the driveshaft as that is the major no no here

any thoughts?...much appreciated

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Ron on Wednesday, April 18, 2001 - 04:18 am: Edit

Why not get a tom woods front drive shaft? The make them custom for you. Bill at GBR has the adaptor ring thing, whole set up is not too expensive.

Ron

Top of pagePrevious messageNext messageBottom of pageLink to this message   By John on Wednesday, April 18, 2001 - 05:25 am: Edit

Clarifacation...3" susp lift...
When you do a 3" lift you will throw castor angle off, pinion angle and also spring pad angle as well. The radius arm off setting(and offset bushings as well) does correct all three areas, but at the cost of creating too much angle at the transfer case with the shorter front shaft. The cardon joint does help greatly. But you still will have an ellitical travel in the cardon u joint, so you will not get the expected life from the u joints. Instead of 80000 miles, you may get only 40,000 miles from u joint life(just a guess).Its the price we pay for tire size and ground clearance. Its worth the trade off if you need the lift IMO. Just inputting thoughts.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Nadim on Wednesday, April 18, 2001 - 06:08 am: Edit

Ron,

What is that kit from GBR?
I cannot carry a driveshaft on the plane down to Lebanon, and shipping it htere is out of the question!..."Will I see it again?"
:)

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Ron on Wednesday, April 18, 2001 - 06:50 am: Edit

Why can't you carry a drive shaft on the plane? It is only about 2ft and maybe 35lbs.

Ron

Call bill, I am not sure of the whole deal. basically you get an adaptor made out of steel to mount a more common bolt pattern drive shaft to the LR T-box

Top of pagePrevious messageNext messageBottom of pageLink to this message   By daivd b. on Tuesday, April 24, 2001 - 02:45 am: Edit

how much would a tom woods front driveshaft cost for a 2" lifted Disco, would this replace the roto-flex?

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Ron on Tuesday, April 24, 2001 - 05:19 am: Edit

Rotoflex is in the rear, the Tom woods would go for the front. Figure 400 for the front and 150 for a used rear and flange. Probably only neceaasry with the 3in kit.

Ron


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