Spring height query

[TC.Barky Valued Member Find all posts View Profile Close TC.Barky]

Hey all,

Got a query regarding rear springs. I had iron man could installed as part of a kit last year and I've done some measurements today in lieu of getting polyairs for the rear. Measurement came in at 250mm or around 9.85" from the top of the spring to the bottom.

Out of interest I rang ironman to see what the spring height is new and they said 400mm! I told them my measurement and they said it sounds like my springs might be knackered and to get them looked at.

My question is what do you guys reckon? Obviously they are gonna sag a bit with the weight of the car and the rooftop tent etc and it doesn't look like it's sagging a dramatic amount just not sure if the measurements from iron man are with zero weight on it and the blokes just not allowing for the weight of the car?

[my.paj Moderator Find all posts View Profile Close my.paj]

I would say the springs you brought are just 40mm lift that are fine until the car is loaded, what you need is springs that have lift and constant load rating.
I had SD lovells but after a wile they sagged so I went HD.
Rick

[my.paj Moderator Find all posts View Profile Close my.paj]

Oh and I think that 400mm they told you is free height ie the spring out the box I think.

[TC.Barky Valued Member Find all posts View Profile Close TC.Barky]

Hmmmmmmmmm.

Well I just went and measured. My initial measurements the day the lift kit was fitted (May last year) was just shy of 600mm at the back from the centre of the wheel to the guard. Today it is 545mm which is actually less than the height before the lift was fitted.

So now my question is thus:

Do you think the weight of a roof top tent and bars (some 80 odd kgs) and the weight of drawers loaded up (lets say 60kg as a very generous guess) would be enough to sag my rear end that much or do I have a problem here. When I spoke to ironman the other day they said the springs were good for 250KG.

They've always been pretty friggin saggy when loaded up with camping gear (feels like my towbar goes down to my ankles) but this seems a bit extreme.

[TC.Barky Valued Member Find all posts View Profile Close TC.Barky]

Spoke to ironman again. They are gonna assess the springs and replace them with heavier duty springs if they have been found to sag

[Paj man Valued Member Find all posts View Profile Close Paj man]

My rear drops 30mm with a 80L fridge of beer and food, heaps of fishing and camping gear etc. At almost double that in yours I'd say the springs are either buggered or too soft.

[Ironman 4x4 Member Find all posts View Profile Close Ironman 4x4]

Spoke to ironman again. They are gonna assess the springs and replace them with heavier duty springs if they have been found to sag

Let us know what the outcome of the inspection is mate.

Cheers,

Matt
Ironman 4x4

[TC.Barky Valued Member Find all posts View Profile Close TC.Barky]

Let us know what the outcome of the inspection is mate.

Cheers,

Matt
Ironman 4x4

Thanks Matt. Appreciate the reply here too. Will be organising an inspection soon. Just out of curiosity what is the general thoughts of ironman on how much the springs should be dropping here? Does it sound extreme for these springs or is there just too much weight on them? Got told they were good for 250kg, does that mean 250kg before sagging and is that 250kg including weight of the car?

[Ironman 4x4 Member Find all posts View Profile Close Ironman 4x4]

Thanks Matt. Appreciate the reply here too. Will be organising an inspection soon. Just out of curiosity what is the general thoughts of ironman on how much the springs should be dropping here? Does it sound extreme for these springs or is there just too much weight on them? Got told they were good for 250kg, does that mean 250kg before sagging and is that 250kg including weight of the car?

Hey Barky,

When we measure sag, we are referring to the free height of the coil i.e. removing the coil from the car and measuring it's height without weight. This provides the most consistant measurement as factors such as full v empty fuel tank, extra gear etc can vary the loaded height quickly.
We expect a coil to settle 5-10mm (of free height) after installation and a bit of driving. More than that would possibly point towards and issue (at which point we'd recommend you get the springs inspected).

As for the weight ratings, the lift height is at the lower end of the load i.e. your current rears are rated from 0-250kg, at 0kg of load (above stock) you will achieve the 40mm of lift in the rear, but with 250kg of load your springs will droop down to approximately the equivelent of stock height (this all can quickly vary depending on where the weight is placed i.e. don't forget leverage of weight at certain points will multiply the load it is adding.

If you are consistantly carrying loads approaching the upper end of the rating it would probably be suggested that you look at more HD coil. For which we now stock a constant load coil for the rear (MITS020C) which is rated from 250kg to GVM.

Hope that answers your questions! Let me know if you want me to clarify!

Cheers,

Matt
Ironman 4x4

[TC.Barky Valued Member Find all posts View Profile Close TC.Barky]

Hey Barky,

When we measure sag, we are referring to the free height of the coil i.e. removing the coil from the car and measuring it's height without weight. This provides the most consistant measurement as factors such as full v empty fuel tank, extra gear etc can vary the loaded height quickly.
We expect a coil to settle 5-10mm (of free height) after installation and a bit of driving. More than that would possibly point towards and issue (at which point we'd recommend you get the springs inspected).

As for the weight ratings, the lift height is at the lower end of the load i.e. your current rears are rated from 0-250kg, at 0kg of load (above stock) you will achieve the 40mm of lift in the rear, but with 250kg of load your springs will droop down to approximately the equivelent of stock height (this all can quickly vary depending on where the weight is placed i.e. don't forget leverage of weight at certain points will multiply the load it is adding.

If you are consistantly carrying loads approaching the upper end of the rating it would probably be suggested that you look at more HD coil. For which we now stock a constant load coil for the rear (MITS020C) which is rated from 250kg to GVM.

Hope that answers your questions! Let me know if you want me to clarify!

Cheers,

Matt
Ironman 4x4

Cheers matt, sounds like mine are dropping a bit farther than expected with weight then as I'd be looking at lets say to be generous +150kg over stock weight and I'm sitting 5-10mm below stock spring height. Am I understanding correctly?

[Ironman 4x4 Member Find all posts View Profile Close Ironman 4x4]

Cheers matt, sounds like mine are dropping a bit farther than expected with weight then as I'd be looking at lets say to be generous +150kg over stock weight and I'm sitting 5-10mm below stock spring height. Am I understanding correctly?

Hey Mate,

Yes if you're sitting below stock spring height then you are likely suffering from too much sag.

[TC.Barky Valued Member Find all posts View Profile Close TC.Barky]

Hey Mate,

Yes if you're sitting below stock spring height then you are likely suffering from too much sag.

Thanks mate, wanted to make sure it was worth the trouble of getting it looked at or whether I was just expecting too much of them. Will post here with the results.

[TC.Barky Valued Member Find all posts View Profile Close TC.Barky]

So I pulled the springs out myself today and rang ironman with some measurements. They're about 5-10mm down each but ironman have said (and I agree) that it's within tolerances. So I wacked a set of polyairs in there today instead (big thanks to Rick for hooking me up with a set!).

Thanks simonc, I'll leave it as is for now - the polyairs have made a big difference. Out of interest if you don't mind posting it in public, what price would you be wanting to offload them for?

[Ironman 4x4 Member Find all posts View Profile Close Ironman 4x4]

So I pulled the springs out myself today and rang ironman with some measurements. They're about 5-10mm down each but ironman have said (and I agree) that it's within tolerances. So I wacked a set of polyairs in there today instead (big thanks to Rick for hooking me up with a set!).

Thanks simonc, I'll leave it as is for now - the polyairs have made a big difference. Out of interest if you don't mind posting it in public, what price would you be wanting to offload them for?

Hey TC Barky,

Glad to hear everything was still within tolerances. Just make sure you don't run with the polyairs too pumped up as you could damage your spring hats (unlikely given the weight you are carrying, but always something to consider in the future if you do start carrying heavier loads).

If I can help you out with anything else please feel free to give me a yell or even just shoot me a PM.

Cheers,

Matt
Ironman 4x4

[TC.Barky Valued Member Find all posts View Profile Close TC.Barky]

Hey TC Barky,

Glad to hear everything was still within tolerances. Just make sure you don't run with the polyairs too pumped up as you could damage your spring hats (unlikely given the weight you are carrying, but always something to consider in the future if you do start carrying heavier loads).

If I can help you out with anything else please feel free to give me a yell or even just shoot me a PM.

Cheers,

Matt
Ironman 4x4

Thanks for the advice Matt, great to have you on here got about 15psi in em for now and ride quality seems ok. Still down a bit on height compared to a mates with the same springs unloaded but its much better. (he's on about 585 I'm on about 570). I could pretty much match the height (580) on 25psi but the ride quality was terrible haha.