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SWB lower arms lenghts?

Posted: Mon Oct 26, 2009 5:46 pm
by SIM79
For those who have a SWBs.
How much suspesnion lift are you running?
What lenght lower arms are you running?
Do you have any vibrations or grinding noises?

I have lifted my SWB with 3 inch coils so it sitting around 4 inches high, I have zero vibrations but when driving I get a wierd grinding noise only when I back off the accelertor or push the clutch in.
I am pretty sure my 15mm longer lower arms are to short and this is why I have these grinding noises, through searching I have found this noise can be stopped with adjustable lower arms, you just make them longer untill the noise stops 20-25mm. I am not keen on adjustable lowers arms that why I want to see what lenght lowers have worked for other members.

Re: SWB lower arms lenghts?

Posted: Mon Oct 26, 2009 6:13 pm
by exV8er
SIM79 wrote:For those who have a SWBs.
How much suspesnion lift are you running?
What lenght lower arms are you running?
Do you have any vibrations or grinding noises?

I have lifted my SWB with 3 inch coils so it sitting around 4 inches high, I have zero vibrations but when driving I get a wierd grinding noise only when I back off the accelertor or push the clutch in.
I am pretty sure my 15mm longer lower arms are to short and this is why I have these grinding noises, through searching I have found this noise can be stopped with adjustable lower arms, you just make them longer untill the noise stops 20-25mm. I am not keen on adjustable lowers arms that why I want to see what lenght lowers have worked for other members.
How will you fit a decent sized set of tires on the back With 20mm\25mm longer lower trailing arms as this will push the tire into the Gard pretty bad on full compression. IE 33" tires rub (rear of Gard) with decent flex and 16mm longer lowers in a GQ IMO.


I've herd of people running the double Cardin drive shaft (Which I believe you have) in whats called broken back configuration. IE, by pointing your pinion at the gearbox so the rear uni has a very small angle in which it operates & making the double Cardin joint do most of the work.
This would also have the advantage of more ground clearance at the pinion & drive shaft. May also fix the drive train NVH (noise, vibration, harshness) issues too

As I said Iv'e only herd of this setup. If anyone on here has more info please let us know.

Re: SWB lower arms lenghts?

Posted: Mon Oct 26, 2009 6:40 pm
by SIM79
exV8er wrote: How will you fit a decent sized set of tires on the back With 20mm\25mm longer lower trailing arms as this will push the tire into the Gard pretty bad on full compression. IE 33" tires rub (rear of Gard) with decent flex and 16mm longer lowers in a GQ IMO.

I've herd of people running the double Cardin drive shaft (Which I believe you have) in whats called broken back configuration.
I don't care if the tyres rub as I am going to do 1/4 cop, I just want the noise to stop.
I removed the double cardinal as I couldn't get my pinion high enough to stop the vibrations. To do it properly would be expensive as shock mounts, coil mounts, panard mount all need to be cut off and then rotate the diff and reweld everything in new spots, plus you need to move the oil filler higher.

Posted: Mon Oct 26, 2009 6:59 pm
by ozy1
honestly, i think you keep the longer lowers you have, and throw some adjustable uppers in the mix and you will be sweet,

Posted: Mon Oct 26, 2009 7:11 pm
by SIM79
ozy1 wrote:honestly, i think you keep the longer lowers you have, and throw some adjustable uppers in the mix and you will be sweet,
Sorry forgot to mention I do have adjustable uppers and gearbox lowered 15mm. With the stock tailshaft I have zero vibrtaions but have the bad grinding noise.

3" lift

Posted: Mon Oct 26, 2009 7:24 pm
by no_1_smittys@hotmail.com
hey mate i am about to put 3" in shorty are you running drop boxes and do reckon its worth doing i have 2" spring and 2" body should i just leave it the way it is

Posted: Mon Oct 26, 2009 8:20 pm
by marin
Might sound stupid, but have you put new uni's in your tailshaft? Because what you are describing sounds like old uni's that have been moved to a new angle. Or just old uni's in general.

Posted: Mon Oct 26, 2009 8:41 pm
by ozy1
uh,some extra info, cool,

Marin could be right on the grinding noise, replace unis, your looking at $50 if you do it your self,

id also be checking your shaft spline, as its also running on a new section, which i think it is more often or not, we have the same prob with my sisters SWB,

Posted: Mon Oct 26, 2009 8:57 pm
by SIM79
marin wrote:Might sound stupid, but have you put new uni's in your tailshaft? Because what you are describing sounds like old uni's that have been moved to a new angle. Or just old uni's in general.
Unis have been replaced, tail shaft has also been unbolted and rotated 180* so it running back to front, both made no difference. Greasing the spline made the noise very quiet but it only lasted for 1.5 hours of driving and then became louder an louder after 3 days it was as loud as it can get.

The spline isn't overextended and has no movement.

What lenght lowers is everyone running on there SWBs?

Posted: Mon Oct 26, 2009 9:01 pm
by ozy1
we are running 16mm longer lowers, and adjustable uppers, we have the same grinding noise, we have found greasin the spline quietens it u[p for a short time, but squeezes the grease out, i really think a new splines the only way to fix it, or lengthen the shaft for 20mm or so and see what happens

Posted: Mon Oct 26, 2009 9:14 pm
by SIM79
ozy1 wrote:we are running 16mm longer lowers, and adjustable uppers, we have the same grinding noise, we have found greasin the spline quietens it u[p for a short time, but squeezes the grease out, i really think a new splines the only way to fix it, or lengthen the shaft for 20mm or so and see what happens
I went to buy tail shaft spacer through snake racing and told them about the grinding noise they guaranteed the spacer would make no difference and they said they won't refund my money when I wanted to return it.

On another forum, last week member put 5 inch coils in his SWB so its sitting around 6 inches and when I questioned him about having any issues he said none. So I told him about the grinding noises, he said he same noise when running stock lenght arms but his were adjustable lowers, after adjusting them out he got zero grinding noises but needed a tail shaft spacer as the spline was to extended.

I think 15mm lowers must be to short for my car. Is anyone running 20 or 25mm lowers and doesn't have any grinding noises?

Posted: Mon Oct 26, 2009 9:38 pm
by ozy1
i think if you run a tail shaft spacer it puts the spline back into the same point where it originally ran, so in reality it should be just a quiet as it was originally,

but then dont quote me on that, its just my opinion

Posted: Mon Oct 26, 2009 9:44 pm
by SIM79
ozy1 wrote:i think if you run a tail shaft spacer it puts the spline back into the same point where it originally ran, so in reality it should be just a quiet as it was originally,

but then dont quote me on that, its just my opinion
I thought the same it does make sense. But when I searched I found a member who tried a tailshaft spacer and it made no difference to the grinding noise and snake racing didn't want to sell me a spacer!

Posted: Tue Oct 27, 2009 5:03 am
by twodiffs
Hey sim, I'm running 4"lift with standard arms. I get vibes around 80-95kph when easing off the go fast pedal, I have looked at stronger and longer lower rear arms (+16mm) but just haven't splashed out yet.
From what I've been told and what I have read on forum, arms 16mm longer should be enough for a lift of our size to stop the vibes...sounds like something else is causing yours but you have nearly checked everything - has your driveshaft been balanced at all??

Posted: Tue Oct 27, 2009 6:18 am
by SIM79
twodiffs wrote: From what I've been told and what I have read on forum, arms 16mm longer should be enough for a lift of our size to stop the vibes...sounds like something else is causing yours but you have nearly checked everything - has your driveshaft been balanced at all??
Yes 16mm lower are perfect for a 4 inch lift on a LWB. 16mm lowers for SWB with 4 inch lift might be to short for the driveline problems. I might get my stock lower lenghted 20mm if that works I will buy some HD lowers at the correct lenght.
I went to get the tailshaft balanced and the told me that it pointless as there was nothing wrong with it before I put the lift in.

Posted: Tue Oct 27, 2009 11:33 am
by AussieJK
get a set of upper and lower adjustable arms my shorty had same problem... they werent adjusted right by pervious owner..... or who ever fitted them... once i adjusted them, it was sweet... also if you dnt already have a set these will be in the for sale section soon as i am going to 150mm wheel base strech and will be doing a custom rear...

Posted: Tue Oct 27, 2009 1:12 pm
by turps
AussieJK wrote:get a set of upper and lower adjustable arms my shorty had same problem... they werent adjusted right by pervious owner..... or who ever fitted them... once i adjusted them, it was sweet... also if you dnt already have a set these will be in the for sale section soon as i am going to 150mm wheel base strech and will be doing a custom rear...
I dont belive he needs adjustable both uppers and lowers. His uppers are adjustable. Maybe they just need to be correctly adjusted.

Posted: Tue Oct 27, 2009 1:33 pm
by ozy1
the problem is, and he has stated that the vibrations are gone, so the adjustable arms have done their job, the vibration issue, i think is completely different,

As he has stated when greasing the spline the noise quietens down, one the grease is squeezed out it comes back,

in my mind it has got to do with the new section of spline slip joint is now driving on, so inmy opinion, it either needs a new spline, or it needs a spacer so the shafts runs in the original area,

Posted: Tue Oct 27, 2009 5:37 pm
by waandy
ozy1 wrote:the problem is, and he has stated that the vibrations are gone, so the adjustable arms have done their job, the vibration issue, i think is completely different,

As he has stated when greasing the spline the noise quietens down, one the grease is squeezed out it comes back,

in my mind it has got to do with the new section of spline slip joint is now driving on, so inmy opinion, it either needs a new spline, or it needs a spacer so the shafts runs in the original area,
mine is the dame with 18mm longer lowers and adjustable uppers, quiet after a grease up but slowly gets louder, mifht just do a high pinion set up

Posted: Tue Oct 27, 2009 6:36 pm
by ozy1
waandy wrote:
ozy1 wrote:the problem is, and he has stated that the vibrations are gone, so the adjustable arms have done their job, the vibration issue, i think is completely different,

As he has stated when greasing the spline the noise quietens down, one the grease is squeezed out it comes back,

in my mind it has got to do with the new section of spline slip joint is now driving on, so inmy opinion, it either needs a new spline, or it needs a spacer so the shafts runs in the original area,
mine is the dame with 18mm longer lowers and adjustable uppers, quiet after a grease up but slowly gets louder, mifht just do a high pinion set up
the hight pinion might seriously help the cause, maybe i should look at this option for my sister shorty and see what happens, too bad i have so much work planned

Posted: Tue Oct 27, 2009 9:07 pm
by waandy
ozy1 wrote:
waandy wrote:
ozy1 wrote:the problem is, and he has stated that the vibrations are gone, so the adjustable arms have done their job, the vibration issue, i think is completely different,

As he has stated when greasing the spline the noise quietens down, one the grease is squeezed out it comes back,

in my mind it has got to do with the new section of spline slip joint is now driving on, so inmy opinion, it either needs a new spline, or it needs a spacer so the shafts runs in the original area,
mine is the dame with 18mm longer lowers and adjustable uppers, quiet after a grease up but slowly gets louder, mifht just do a high pinion set up
yes im in same boat, got diesil motor stripped down in the shed, a ute chopped zook, new house, work and weekends to try work around :bad-words: will i need to get the pre load and the centre re set as i do this?


the hight pinion might seriously help the cause, maybe i should look at this option for my sister shorty and see what happens, too bad i have so much work planned

Posted: Wed Oct 28, 2009 3:51 pm
by ozy1
i would say so because you are running on the back side of the gears,

Posted: Wed Oct 28, 2009 11:56 pm
by big red
with my 50-60mm lift and 33's on the mav wagon the tyres are already just touching the rear of the rear wheel arches so longer lowers won't work on mine.

will have to try adjustable uppers to get rid of the vibe

Posted: Thu Oct 29, 2009 6:25 pm
by waandy
big red wrote:with my 50-60mm lift and 33's on the mav wagon the tyres are already just touching the rear of the rear wheel arches so longer lowers won't work on mine.

will have to try adjustable uppers to get rid of the vibe
have you got x member packers? i have mates running 3 inch lifts with no vibs or packers, it is lwb isnt it?

Posted: Thu Oct 29, 2009 10:57 pm
by big red
waandy wrote:
big red wrote:with my 50-60mm lift and 33's on the mav wagon the tyres are already just touching the rear of the rear wheel arches so longer lowers won't work on mine.

will have to try adjustable uppers to get rid of the vibe
have you got x member packers? i have mates running 3 inch lifts with no vibs or packers, it is lwb isnt it?
its a HD 2" so unloaded it vibrates a bit.
its a LWB.

if i get the front and rear flange faces on the rear tailshaft parrallel then it should be right.

Posted: Sat Oct 31, 2009 11:07 am
by Nelso
My shorty ran a seven inch lift for years with no problems and has had the 4 inch lift that's in it now for even longer. The double carden option will solve all of your problems, just cut and rotate your spring perches and space out the lower shock mounts (or cut them off and rotate them too)and trim the bumpstop platform on the diff so it doesn't hit the shock. I didn't change the filler plug and the rear diff has been out a couple of times over that time with no issues what so ever. If you are that worried just jack the rear up a bit when you fill the diff with oil.

It is much easier fitting the DC than stuffing around with standard unis for that much lift as you possibly will never get it right.

My lowers are 25mm longer than standard as well.

Posted: Sat Oct 31, 2009 12:15 pm
by brad-chevlux
Sim, talk to josh about the tail shaft spacer, I know he had one of the machinists at his work make his for him.

would end up cheaper then snake ones, and if it doesn't help it won't have cost much to find out.

I can help you with the cut and shut on your old arms if you want to try a 20mm longer arm.

Posted: Sat Oct 31, 2009 9:01 pm
by SIM79
Nelso wrote:My shorty ran a seven inch lift for years with no problems and has had the 4 inch lift that's in it now for even longer. The double carden option will solve all of your problems, just cut and rotate your spring perches and space out the lower shock mounts (or cut them off and rotate them too)and trim the bumpstop platform on the diff so it doesn't hit the shock. I didn't change the filler plug and the rear diff has been out a couple of times over that time with no issues what so ever. If you are that worried just jack the rear up a bit when you fill the diff with oil.

It is much easier fitting the DC than stuffing around with standard unis for that much lift as you possibly will never get it right.

My lowers are 25mm longer than standard as well.
I will do this a last resort as its bloody expensive.

Posted: Sat Oct 31, 2009 9:03 pm
by SIM79
brad-chevlux wrote:Sim, talk to josh about the tail shaft spacer, I know he had one of the machinists at his work make his for him.

would end up cheaper then snake ones, and if it doesn't help it won't have cost much to find out.

I can help you with the cut and shut on your old arms if you want to try a 20mm longer arm.
Thanks Brad, I might hit Josh up for a spacer and Mat from Kowari has a spare set of lowers from his old comp truck for me to try.

Posted: Sat Jan 16, 2010 4:34 am
by HellfisH
Did you get your problem sorted out Sim, I have the same grinding noise with my shorty, so I'm interested to see how you fixed it or do you still have the problem.