Nissan Patrol 4x4 (Africa)

Yeah, agree Peter,.. its no secret that Original Nissan Rubber is best for flex and front end feel,.. so like you say, to keep them you would have to x-link, or use drop arms, or change the linkage point at the chassis end (read : drop boxes).

Obvously, for most, Caster bushes will do the job nicely, particularly those not looking for extreme wheel travel but rather good road manners.

I'm glad to see such a cool design of bushings, that doesnt break the bank either. Im intrigued to see over time how the fair, and if they might swivel in the arm? The usual story is to have a Metal outer, which is pressed or knocked in, which i assumed would adhear to the arm via friction, holding it in place,.. these dont, and these also seem very easy to install. Keep us posted Mike.

Russ, due to something Clem asked me for, I have been investigating rubber bushes and how they SHOULD be manufactured. I will explain the two processes, so sorry if this gets a bit long-winded and technical, but somebody may get some use out of this and I think it might put your mind a little bit at rest on your question.

The cheap (and incorrect) way of making these bushes, and unfortunately also the one all local manufacturers I know about use, is to simply make a jig to hold the two yubes in position, then apply some bonding agent to the correct areas, and then insert the rubber (rubber or EPDM is softened with heat and pressed in, poly is mixed and poured) into the gap between the two tubes. The assembly is then placed in an oven or autoclave to cure. Simple and easy.

The problem is that rubber, and to a lesser extent polyurethane, shrinks while curing. So you end up with a situation where the bonding agent is under extreme tensile stress, and it invariably fails pretty soon.

The right way to do it is to make a seperate mold, with sizes very carefully calculated. The whole mould is coated with relaesa agent, the rubber or poly is inserted and cured, then removed from the mold. The sleeves are manufactured especially with rough surfaces where it will contact the rubber. Now the inner tube is cooled in liquid nitrogen, and the rubber is heated, then dropped over the inner sleeve. Then the process is reversed, with the rubber and inner sleeve assembly chilled in liquid nitrogen, and the outer sleeve heated and slipped over.

If the calculations for the mold were done correctly, you now have an asembly where the rubber is under pretty serious compressive stress, and this is what holds it all together. No bonding agent.

Thus in theory, if these fancy poly bushes have enough interference with the hole in the suspension arm, those bushes will not move, ever. And you have gained a little bit of flex because your rubber section is effectively thicker due to the omission of the outer sleeve (although probably not over a standard bush because the inner sleeve here is much thicker.

My major concern is with the polyurethane itself. I have been told that poly doesn't handle high-force vibration well, eventually disintigrating. And this exactly the type of loading expected in this application.

So personally I prefer drop-boxes or X-links or some other method to recover the caster angle without having to move away from concentric rubber bushes.

Bloody good Post Pete, ..thanks for sharing your wisdom once again. totally explains it.

So in essence however,.. these bushes that Mike got are/could be the best yet. ... ?

Certainly the best Poly-looking I have yet seen, but I don't think they are as good long-term as the genuine article.

However. they do provide a cost-effective way of fixing the problems we cause with lift kits.

Great post Piet

Like you said, poly bushes isn't my favourite either and I also prefer rubber bushes. The biggest issue for me is correcting my caster in the most cost effective way and I am very keen on trying these new adjustable bushes.

I think in future I will definitely invest in the drop box or x link option

haha, Mike..... put these in ! you keeping us in suspense here!

(Ps: You setting them up at 2.5' ?)

Ha ha Russ, belive me when I say that I want them in more that you
Im just not finding the time to get to them, but they will be in before Monday.

I think it is going to be 2deg offset not 2.5 like the salesman said.

Ok so finally I got some time yesterday to install my new caster correction bushes.
To make long story short, it was quite a job!! took me about 5 hours of nonstop commitment to get them changed plus some bushes and lots of frustration when I ran out of hands as it iwas just myself and I doing the job.

So obviously I started by jacking up the car and supporting the chassis with some trestles, then I just removed the one rear bolt and the two on the dif and out she comes.
On closer inspection after removal you could clearly see the centre bush has completely broke loose from the rubber section.
Close up of the bush
I don't have a press to get the old bushes out, but there is a old trick that is very easy to get them out. Just drill some holes in the rubber to brake the centre piece of the bush out and then use a normal hack saw to cut through the bush. It then comes out very easy using a chisel and hammer.
The bush removed
Once the bushes were removed I sanded and cleaned the holes and then simply installed the new ones as per instructions on the Ironman website.
here is how the new installed bushes comare with the old standard bushes.
The really hard part of this excersize is to mark the radius arm directly under the bolts 90deg with the ground. You use these marks to install the new bushes.

nicely done bud !!

Netjies dude...