[Tyddy]

Hey, I've be looking at suspension lift kits and have come down to the Old Man Emu Lift Kit but just have a few questions, I am looking at putting on a Roof Top Tent which would way bout 50 kg and also just camping supplies in the rear of the car. I have heard that the OME kit is quite soft I was wondering if any would know if it would sag with that type of weight?

Also I don't have a bulbar/winch now bout in the distant future may want one am I better to get the heavy duty springs in the front now or will that cause me problems without having the bulbar/ winch on the car?

[pete_79]

Don't do it man.....!

50kg on the roof of a Jimny is about 35kg too much. Just saying from personal experience.

[Jezza86]

HD springs are fine wo winch, dunno bout BB

[Gwagensteve]

OME springs seem to only be suitable if you don't overload your car. (Funnily enough)

Most Jimnys set up as you describe are well over GVM. Apparently OME should have foreseen this. Or something.

It would be easy to be flippant and say if OME springs are too soft, you have the wrong car for the job, so I won't say that. I also won't say that a canny insurance company would deny a claim if it's evident the car is over GVM. Without appropriate engineering approval (as is possible with landcruisers, for example.)

I will say- work to stay under GVM. The whole car will thank you.

Steve.

Ps I do understand OME jimny springs are amongst the softest lift springs available. That's normally considered a good thing, but I also see that Jimnys have a high rear COG and stiffer springs do help to make the car feel more stable when laden, even if you're not over GVM.

[pete_79]

How much would you say your tent weighs Jezza?
I guess at least yours is flat, I couldn't imagine having one of those big heavy square things on the roof.


I know the one time that I put 50kg (or maybe a bit more) on the roof to go bush it was fine on the highway, but as soon as we got off the smooth stuff it was bump stop driving all they way.
It was dangerous and bloody annoying going from front right bump stop to rear left bump stop at every single pothole or dip in the road.
That was on the standard suspension and I swore I'd never load it up like that again, one trip like that is more then enough.

Even now with the Dobinsons suspension (which is really good and would recommend to anyone) I still only put the absolute minimum on the roof.
It's usually the fold-up chairs, the poles for the tarps and a shovel that go on top or it's our vinyl bag with all the sleeping gear which I've weighed and is 28kg if we take extra blankets for the kids in winter. That's it.



As Steve says, it's not easy keeping under the tinny load limit of the Jimny, but it is possible.

Thanks to my OCD and weighing everything we take, I've pretty much mastered the art packing our Jimny to keep within the GMV.
I was guilty of over loading once or twice, but after doing quite a few good trips over the last couple of years we can easily pack a family of 4 and our gear for a weekend away. Most of our gear is lightweight hiking type gear, the misses is very practical and doesn't need all the creature comforts and the kids are still only small (like 15kg each).

But if we're going for anything longer the 3 or 4 nights or going with a group where we need more gear we take the trailer. It's just not worth over loading in my view.

[Jezza86]

i think there's value in doing a little math here.
most people will be over gvm. i wont refuit that.
but
OME springs were always turning, twisting relocating and noisy. the car was softer compared to the stock suspension. so i dare say the OME shocks were part of the problem too, not just the spring rates.
1,050+ 63 kg for the Hannibal impi + the bullbar is 35kg+ 45 for the winch with steel cable=1193 kg
put my ass in the drivers seat adds its a extra 100kg closer to the 1420kg GVM, but still 127 kg under gvm, before a second passenger, or god forbid luggage. so yes. close to gvm. mabie a touch over at one stage.
but
if i take my winch and pod off, which i did for quite a while, im back down to 1185. the springs still click on tar roads, and never seam to seat and they unseat even after repeated attempts to relocate them again and again. to top it off the whole care is unbearably soft. this is 335 kg under gvm. it sucked, and i hated it so much i sold the lift for $100 at a garage sale. it didnt flex anywhere near as well as what ive got now, and meant i just couldn't explore the places i can get to now.

the reality is i had the hardest springs in their catalouge and found that my rig was no more capable over stock for 1100 bucks. that was my experience with them.

[Mike57]

I had ARB add 5mm spring packers to my rear springs to lift them a little so when fully loaded the car was level. This worked fine and did not void any warranty. I find the soft springs are good on rough roads but as Steve says there is too much side to side movement on the really rocky Vic high country roads. On those trips I am lightly loaded. On outback trips with heavy loads I think they are perfect.

I would not put a 50Kg tent on my roof either although I have probably had 40kg on the roof on a few outback trips but never on mountainous roads or sand driving.

Mike

[E30luv]

I've got the OME Lift in my Jimny with rear draws, 100AH battery and 40L Waeco in the back constantly and it hasn't sagged at all. Even fully loaded for camping it might of sagged 10mm. Maybe I just got lucky with my set, because I also read that they were quite soft. Definently softer than stock in terms of ride but they haven't sagged.

[squibby]

Tyres and wheels aside, My Jimny Trekker was probably one of the heaviest Jimny's out there from the axles up, Winch, Bars, Dual batteries, Sliders, Armoured front diff, Armoured transfer, Armoured Tank, Front Bar, Rear bar with swing out tyre carrier, Roof box commonly laiden right up, back seats folded flat and laden to the max for camping trips.

I had the GVM upated by engineer along with the rest of the vehicle. I had the hardest OME kit and can't really say anything bad about it. Of course it sagged when first installed at the front, and the front coils went all banana shaped so you just have to bite the bullet and get it set up properly. I had to fit 25mm spacers up front and fit anothe 10mm on top of that to the front right and rear right. Then I fit the correct castor correction bushes in the front to straighten out the front coils.

OME suspension was excellent and really appreciated the soft springs with Hard dampers combo that it offers. Vehicle will roll more than stock but the dampening is much better than stock in my opinion and it felt fine when fully laden and I feel it handled better than stock.

[pete_79]

Out of interest; how much did the engineer increase your GMV to?
Was it just the shocks and springs that allowed the higher payload or other additional mods to the suspension set up?

[Gwagensteve]

This is maybe a little bit off topic, but I have to ask this.

What do people mean by "sag" in relation to jimny suspension?

I consider "sag" when the car looses height over a period of time even though weight stays the same

Factory leaf sprung toyotas of the 1980's were renowned for this, for example.

Coil sprung cars shouldn't sag at all. If the car looses height over time (as in over some weeks) then there is a problem with the design or construction of the spring. This raises a secondary issue with the Jimny suspension design. From what I've seen, it's very hard to build a long, soft front spring that doesn't bind when fully compressed. It appears that even OME springs, with a very conservative lift height, basically can't get the axle onto the bumpstop. It might be possible that heavily laden Jimny's with a high spring rate in the front are actually bottoming their springs. This might lead to sag. I don't think this is a problem with the rear.

In short, no factory suspension is designed for lift, but IMHO, Jimny suspension is very sensitive to spring design. I reckon a Jimny front end is designed for 6" of travel, 3 compression, 3 droop (stock) taking the front axle weight over its rating, and then trying to add 2" of lift, means there's just too much spring trying to fit in there.

Just some thoughts. Sorry if anyone thinks it's taking the tread off track.

Steve.

[pete_79]

With nothing in the car my stock springs where 20mm lower in the rear then the front when I changed them at 12 months old. One would assume the front and rear would be the same height from the factory, so I would call that sag.

You are right with the front springs.
I never actually checked the stock front springs when fully compressed to see if they hit the stops. But with the 50mm lift the front is off the bump stops when fully compressed.

The rear still hits the bump stops with the 50mm lift installed.

[Jeff1400]

We changed the suspension in out prado. Lovells coils/ bilstien shocks. +50mm
6 months later it didn't look right. One side different to the other. Called the guys who put it in, they asked me to measure from centre of axle to the guard. It had lost about 30mm one side, 20mm the other. They gave me new ones. 6months later the same, they gave me new heavier duty springs. They sagged as well but not so much, maybe 5mm. Bilstien struts have adjustment for ride height. We bumped that up a click and after the initial sag/ settling, it has stayed. That's about 9 years ago now always had dual batteries, deluxe ARB winch bar with winch. I'm only talking the front springs. The rears are still the original Lovell's springs first put in.
Awesome ride. Good height, great towing a deluxe camper trailer. Full of fuel (180lt) and gear
Coils will still sag, or settle I should say with normal use. But overload them constantly and they will sag in the true sense of the word. (At a constant weight over time). All the springs were originally a medium duty, now I run medium rear, heavy fronts.

Sounds like OME are close on their spring weight for the suzie, In normal trim. But a bit under weight for the loaded up car.

[fordem]

Gwagensteve wrote:

I consider "sag" when the car looses height over a period of time even though weight stays the same

This is also my interpretation of "sag"

Quote:

Factory leaf sprung toyotas of the 1980's were renowned for this, for example.

And the older series Land Rovers

Quote:

Coil sprung cars shouldn't sag at all.

I've come across this statement on the web before, and for the life of me I cannot understand why people feel this way - coil springs come in two forms, compression springs (as used in vehicle suspension) and extension springs - I know from personal experience (as an accounting machine technician) that extension springs can be over extended, deformed and weakened - which would be a little harder to do with compression springs, but I assume it could be done.

Quote:

If the car looses height over time (as in over some weeks) then there is a problem with the design or construction of the spring.

What about when the period of time is a few years?

[squibby]

Gwagensteve wrote:

This is maybe a little bit off topic, but I have to ask this.

What do people mean by "sag" in relation to jimny suspension?

Steve.

Good point. My jimny with OME did not 'sag' at all over the two years I had the kit. When I mentioned 'sag' in my previous post I was probably incorrectly applying the term to the initial installation of the coils. I presume they are designs so that a standard jimny will sit level, however with my extra weight jimny they needed to be levelled out differently at all four corners which I accomplished with the spacers/packer.

[squibby]

pete_79 wrote:

Out of interest; how much did the engineer increase your GMV to?
Was it just the shocks and springs that allowed the higher payload or other additional mods to the suspension set up?

Can't remember what the Engineer increased the GMV to exactly, however he did so on the following basis:-
a) some of the extra weight was unsprung weight associated with the larger tyres, so he made a couple of educated guesses regarding this
b) the suspension had been upgraded allowing an increase in GVM
c) he had performed a brake test and it passed no problems
d) he had my weighbridge certificate and taken into account how much fuel weight i had on board.

Armed with the above he just calculated how much four adults would weigh, a full tank of fuel and a little allowance for luggage and added that to the actual weighbridge weight and then increased the GVM accordingly. The figure looked reasonable so he was happy to engineer it.

[Jezza86]

Gwagensteve wrote:

In short, no factory suspension is designed for lift, but IMHO, Jimny suspension is very sensitive to spring design. I reckon a Jimny front end is designed for 6" of travel, 3 compression, 3 droop (stock) taking the front axle weight over its rating, and then trying to add 2" of lift, means there's just too much spring trying to fit in there.

i think 3+3 is a little conservative, stock i could get 8" before a wheel would float. the biggest limitation to the stock setup, its the front roll stiffness, from the anti roll bar.
the front diff may be on bump stops one side, but the other wouldn't be at full extension as the swaybar would take the weight and limit travel, not the shock.

[Gwagensteve]

I wasn't referring to flex, only vertical travel. I don't think jimny's have 200mm of front vertical travel- that's the same as a 80 series land cruiser.

[Gwagensteve]

fordem wrote:

Quote:

Coil sprung cars shouldn't sag at all.

I've come across this statement on the web before, and for the life of me I cannot understand why people feel this way - coil springs come in two forms, compression springs (as used in vehicle suspension) and extension springs - I know from personal experience (as an accounting machine technician) that extension springs can be over extended, deformed and weakened - which would be a little harder to do with compression springs, but I assume it could be done.

You've answered the cause of deformation in extension springs in your statement - overextension. Overextending an extension spring will definitely weaken it and cause it to loose rate. However, it's not quite as easy to over compress a compression spring, so long as the spring was correctly designed for its application.

There are literally tens of millions of coil sprung road cars on the road, and even at great age, they don't sag. That's because the working range of the spring isn't exceeded. The issue comes when a longer than stock spring with thicker wire is jammed into a space designed for a shorter, spring with thinner wire. It's possible under these circumstances to over compress the spring, and this can lead to fatigue and either a loss of rate (sag) or failure.

In the case of Calmini, they even "design" this in to their springs - they hard bottom them on compression, and as such they loose rate once they have been bottomed a few times - that's why Calmini (and only calmini) say their springs need to be "settled in" and the car will sit high before it's driven for a while.

Quality aftermarket springs are "scragged" which means they are over compressed in a controlled way during manufacture. After that, they should never loose height if they are kept in their working range.

This leads to a comment about spring spacers. In my opinion, whenever spring spacers are used, the bumpstops should be spaced by the same height as the spring spacer. This is to retain the correct working range of the spring.

With reference to Jimny front springs, it appears impossible to design a higher rate/longer spring that still allows the front axle to reach the bumpstop. This is a function of the design of the jimny front end and isn't down to the spring maker.

Steve.

[Marko_SJ]

A little off topic, but a word about sag.

Gwagensteve wrote:

This is maybe a little bit off topic, but I have to ask this.

What do people mean by "sag" in relation to jimny suspension?

I consider "sag" when the car looses height over a period of time even though weight stays the same

Factory leaf sprung toyotas of the 1980's were renowned for this, for example.

Steve.

When it comes to motorcycles (and I assume other vehicles will be similar), this is sag:

There are two measurements:

A point on the body of the vehicle is marked to measure from.

You can use an unsprung point of the vehicle as the second reference, I just use a part of the swing arm on my bike.

The vehicle is put on blocks / stands and the distance between the two points is measured. This obviously gives the uncompressed length in regards to your reference point.

The vehicle is put onto its suspension but is kept unloaded, the difference in measurements is called the "free sag, or static sag"

The rider/driver and any load carried by the vehicle is added to the suspension so it compresses further, this is the "rider sag, or race sag"

These measurements are used ensure the correct spring is fitted, could go on about this but it is unrelated to the topic.

So to the point: What I am saying is that any change from the uncompressed length is "sag", so a car riding lower due to the springs softening/flattening/fuxxoring is an increase to sag and that Gwagen is right ( as usual) .

Edit: for anyone interested - http://www.procircuit.com/content/Setti ... %20Sag.pdf

[pete_79]

Hmmm. This is AZ so maybe we need pictures to help?

These where my standard springs 12 months old, empty car on level ground, measured from centre of hub.

Front.



Rear.


Front= 435mm
Rear= 415mm


And for the front springs.
Dobinsons 50mm lift beside standard. The lifted springs are the same length but are slightly thicker gauge and have almost 2 more full turns.


Steve is right, the lifted front springs do not let the diff hit the bump stops. I haven't actually measured it, but they are a not even close to touching.

But the lifted rear springs do compress enough to hit the bump stops just fine.

[Gwagensteve]

Marko, I agree with your definition of sag for two wheelers. It's not the normal definition for cars though.

[fordem]

Gwagensteve wrote:

You've answered the cause of deformation in extension springs in your statement - overextension. Overextending an extension spring will definitely weaken it and cause it to loose rate. However, it's not quite as easy to over compress a compression spring, so long as the spring was correctly designed for its application.

There are literally tens of millions of coil sprung road cars on the road, and even at great age, they don't sag. That's because the working range of the spring isn't exceeded. The issue comes when a longer than stock spring with thicker wire is jammed into a space designed for a shorter, spring with thinner wire. It's possible under these circumstances to over compress the spring, and this can lead to fatigue and either a loss of rate (sag) or failure.

One of the reasons I am curious about this is that I have seen spring manufacturers - OME was one, there were others - who have claimed that the OEM springs will sag with age, and one of my vehicles is a Mitsubishi Pajero that I acquired with sagging front springs.

When I got the Pajero the steering was quite vague - it went in the general direction in which it was pointed, but appeared to have a mind of it's own - there was noticeable negative camber on both front wheels, the ball joints were fine and so I assumed the control arm bushes were gone and set about replacing them - as soon as I pulled the arms off, I recognized that the bushes were intact, but since I had them, I replaced them.

It took several weeks of head scratching before I noticed, by accident, that with the car on level ground, the control arms were not at the same angle - the right side was almost horizontal and when I measured, I discovered the right front was roughly 20mm lower than the left. It took almost a year to source new OE replacement springs, which corrected the problem, but when I had the springs out, I compared them - there was very little visual difference, but, if you grabbed them in both hands and squeezed, the old driver's side spring was noticeably weaker.

I have two other coil sprung vehicles, one, a Suzuki Swift on which the rear springs also "lost" their ability to support the weight, and my GV which appears to have the OE springs and no sign of sag.

[atari4x4]

and coil bind will also kill a coil spring real quick...

[killazook]

So what has been said here one should extend the jimnies front bumbstops to stop the springs binding and effectively making them last longer