Suspension options for a 109

The springs on my 109 project have well and truly rusted solid, and the dampers are equally suspect. So what's the best options regarding replacement? Conventional springs or parabolic? Which dampers? All too often any comparisons are between knackered originals and shiny new replacements which isn't very helpful.

Not expecting the truck to be heavily laden with bricks or do heavy towing with it, so something softer on the rear might be preferable. Though I might yet put a soft-top on it with a couple of benches in the back. Is an anti-roll bar available and worthwhile on leaf springs?

You could just leave it as it is. Once you start using it, the rust between the spring leafs will grind away and the ride will improve, mine did.

Col

Another option is to renovate your existing, I didn’t want to risk buying cheap ones , so I split the front leaves derusted each leaf , POR 15 metal prep and paint, with some graphite day spray grease, I’m happy with them and doing the rears next year, no crashing bangs going over humps now
I did break one of the clamps but easy enough to make another with big hammer and vice and rivet back on, some say greased normal springs nearly as good as parabolics
Open top is fun

Don't try to renovate, if you're saying that The shocks are done (leaking?) then the U bolts and the bushes are shot. It'll never pass an MOT and irrespective it's probably dangerous to drive it on the public highways. I strongly suggest you replace the whole lot, removing the shock absorbers is easy. Cut the split pin with a junior hacksaw and the top bolt should be easier as it's away from the crud and splattered with engine oil. Follow the workshop manual to jack up the chassis and axle and cut the whole lot off with a grinder. It's a total **** of a job.

To follow on. If you've got a garage it'll make it easier but it's still a dirty, tricky job. To put the safety and drive ability of the landy a complete replacement is the only option if it's totally rusted. Correct U bolts are critical and the spring plate. I

Colthebrummie said:

You could just leave it as it is. Once you start using it, the rust between the spring leafs will grind away and the ride will improve, mine did.

Col

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^^ I would try this first
If the shocks have gone replace them standard OEM Armstrong shocks are good and cheap. Unless the springs are sagging badly the first thing I would try is to spray them in some form or oil (I used old gearbox oil) put 1/2-1ton in the back and go and repeatedly drive along a road full of speed bumps. This just speeds up the process of normal use mentioned above, I did this when I first for my series and the difference between start and finish was enormous. The combination of oil, weight and bumping it along got the spring leafs moving again rather than being rusted solid. Obviously this will not be as good as a renovation or replacement but it will give you some more life out of your existing set and improve the ride for very little expense or effort. After doing this I ran quite happily for another three years until one of the spring finally broke and I then replaced everything.

Agreed re oiling, my ride improved massively after oiling. I filled a squeezy bottle with 50 / 50 old oil and diesel and kept spraying them.If the leafs are still together I would do that and drive about, new std shocks - they seem to work well. If they are blown - the rust has pushed all the leafs apart then they may be shot.

FlyingPete said:

The springs on my 109 project have well and truly rusted solid, and the dampers are equally suspect. So what's the best options regarding replacement? Conventional springs or parabolic? Which dampers? All too often any comparisons are between knackered originals and shiny new replacements which isn't very helpful.

Not expecting the truck to be heavily laden with bricks or do heavy towing with it, so something softer on the rear might be preferable. Though I might yet put a soft-top on it with a couple of benches in the back. Is an anti-roll bar available and worthwhile on leaf springs?

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Do you have a budget in mind?

Sadly I don't think there is a whole heap of choice on the market today. Parabolic springs have the potential to ride much better. Although many (at least for 88's are heavy duty so still ride very hard unless loaded. So check out the spring rates).

The stock springs will soften up with use, but this may take quite a bit of time and require you to load it heavily. And may depend on what springs you have on there now. As there were different rated spring packs back in the day. And of course you have no way of knowing if the springs on it now are OEM or have been replaced at some point previously.

Same is true with renovating them. No reason why you can't do this, you can even remove of add leaves too to alter the spring rate. It just requires time and effort to do. So is the best route if you want the cheapest. Putting new springs on will be a lot less effort.

Parabolics will induce more body lean as they are generally a more compliant spring. So the addition of an anti roll bar might be sensible. But probably best to try first and see if you feel like it needs one. I think there are kits for doing this, but will likely require a bit of R&D on your part.

As for shocks. This depends on the springs. The stock shocks or direct replacements will work fine with stock springs. With parabolics however they will get overworked and you'll want a more modern shock.

The shock length is also what largely dictates the suspension travel on a Series motor. So if you want it more off roady with more travel you may want to consider some longer shocks than stock ones. Depending on what you go for you'll be fine with the stock mounts, but may end up bending the spring backwards under full compression. Extended shock uppper mounts would solve this, but would have to be completely custom.

I've always like Heystee, but they are pricey and last time I look they didn't seem to have much for sale (suspect the market has shrunk as there less Series vehicles today than 10 years ago). They offered their own design parabolic with +2" shocks.

Rocky Mountain spares also do/did offer some nice parabolics and +2 ProComp shocks.


Lastly and no idea if possible. But the Santana PS-10 (looks like a 110) is based on a 109 platform. It used parabolic leaf suspension. Which I suspect but don't know for sure would fit a 109. If you could buy some OEM spec springs for a PS-10, it would probably suit a 109 very well, assuming they fitted.

I tapped a screwdriver between my springs and squirted some oil in but its a slow process, and pull the screwdriver out slowly or you'll get squirted in oil. Now noticed the outside of the damper has a hole in it and the rest of the top section is thin so bought some new Armstrong dampers with bolts for less than £38. Not sure if the oiling has made any difference but at least it should have freed them up a bit.
FFG

To get oil between the leaves jack up the body and the leaves open up some. If they don't it realy is time for new springs.

When I bought my 109 it had been parked up for a few years and the suspension was solid, I thought to buy new springs as a priority but after driving it for a couple of hundred miles the old springs were fine although still very rusty looking.

Col

tottot said:

To get oil between the leaves jack up the body and the leaves open up some. If they don't it realy is time for new springs.

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If they don't that is where you need to oil the outside, load it up, and bang it about over a few bumps. This should free off the springs enough to then jack it up to spread them and repeat the process. In all I did it about 4 times over the period of about a month. It sounds like mine were in a similar state to @Colthebrummie as again the vehicle had been parked up before I got it. Springs are expensive so a little time (zero cost if you use old oil) to see it they can be imporved is well worth investing. If the still need replacing at the end of it you are no worse off.

After soaking the leaves in oil, wrap them in cling film to keep the oil in when bouncing it about.