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Spring advice needed


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Now I have a set of Monroe gas shocks to go on the 90 I also need to think about springs at the same time - because I hate taking front shockers off so I only want to do it once!!!

So, I have a set of almost brand new 90 rear springs I just "acquired" in a swap for some of the rubbish under my bench, these are, according to the jbarge site the std 90 rears NRC9448 and NRC9449 as they are blue/red and yellow/white, so according to that site 225lb rating.

Does anybody know the rating of the RKB101230 and RKB101240 springs as fitted to Defenders now ... stronger than the old p/no or the same? I am not 100% sure but I think the RKB ones are what mine has on the back as I think all new 90s come with those on the back, but that p/no isn't listed on the jbarge site.

The main thing really is whether I just put the 9448/9449s on the front and leave the rears as they are (which I will do if the ones currently on the back are heavier than the 9448/9449, as apart from anything else it means less work!) or put the older and therefore slightly softer rear springs on the front, and put the new ones I just got on the rear (which I will do if they are all the same rating). I could of course take the rears off and clean them up/sit them side by side with the ones I just got but as I may not need to take them off I'd prefer to find out if there is a difference the lazy way ;)

The object of this is to restore a bit of height at the front, because since I have the winch etc on there, the front springs have gone a bit flat and fitting 90 rears is a good way of sorting this out. Also they were "free" which is good :)

Any info please?

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90 rears will bring the front back level after a winch is fitted.

but better still fit some aftermmarket ones!(never miss a chance for upgrade)

my latest choice has been the best so far

handles really well sits level and carries the load fine.

Your latest choice being what then?

I have done some more digging anyway, the ones on the back of the 90 are not the RKB ones they are the same colour code as the ones I just got, 16.2mm dia and I got a set of the RKB ones and they are 17mm diameter so they must be heavier. I think I'll just put these on the front and see what it looks like then maybe get a set of spacers for under the back springs if it looks nose-high.

You are forgetting two important things Tony - the springs I have are

1) Free

2) Here

Neither of which should be underestimated :P anything I order now probably won't be seen this side of Christmas!

What I really want on the back is a set of Disco rears but I can't get any of those at the moment. My old red 90 had 90 rears on the front and 90 rears with +1" Mill Services spacers on the back and that was pretty much ideal. Much higher and it won't go in the garage anyway :unsure:

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i ran disco rears on the front of my 110 for the extra ht with h/d 110/130 rears on the back - an excellent setup.

as for a 90, slightly different matter, mine came with a procomp setup which has raised it about 2" and i will stick with them for now as the articulation is good with good onroad manners. the main advantage being they are quite long springs for good travel but dont bunch (egcoild dnt touch in std situ)

anywya the point of the reply is that i think i have a set of disco rears in the garage - what colour should they be? ( H reg 200tdi age)???

If i have, steven you can have them i currently dont need them.

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Right can of worms you have openedbhere.

There are a few things to consider (other than there free and there looking at you :lol: )

90's basically are classed by LR as an Agricultrural 4x4.

They are expected by farmers to be able to carry silly amounts of weight without any issue, and theres where the fun starts.

I am right in the middle of working out my own spring problem, and yours and others won't be a million miles away from the same issues.

1. You can EITHER have axle articulation OR carrying capacity, not both.

2. The 90 has 175/178 front 225 rear, and NO load leveller.

3. Range rovers have 170 ish rears, but they have a load leveller.

The leveller (when it hasn't siezed on ) pumps up under load to gibve the same ride hieght as unladen, the 90 doesn't have this, it just has HUGE spring in the back to compensate.

So, either you go for comfort and articulation, OR carry loads capacuity.

thats why you have 225 in the back.

Fronts, you onmly have 175/78, and frankly the weight of the MM is minimal, what eklse have you done ot added to the 90 to need a 55 lbs increase in springing ?

if the 90 has dropped a bit from weight maybe put a longer or slightly harder spring in


NRC 9447 blue yellow 175 @ 14.80 inches

red white 170 17.71

green yellow 170 16.2

green yellow blue 178 18.18

pink purple 180 16.47

etc etc

I would advise that you use LR90 Trev exellent spring calc, but for this you do need to weight your 90 so you know what the front and rear axle weights are, this will then compare the weight and spring length poundage and tell you how much higher your front will be than now, and also it will work out the rerars on the front.

Personally, I think unless you have a load of extra weight on the 90, OR unless you wnat to carry loads of weight about 225 on the front could be too much and make for a hard ride.

Probably not a definateive answer I know, but 1st we need to kinow what you are looking for, load capacity or ride comfort / articulation, that then will help guide.


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I'm not that scientific!

All I know is

1) I used to have some 90 rears on the front of the old red 90 and it sat about where I wanted it to (springs were changed by previous owner but he told me they were 90 rears)

2) I have some free 90 rears available right now :)

3) the front of the 90 is really sitting quite low compared to what it used to when I first got it (and before the MM went on)

You are right it does make the ride quite noticably harder than std springs but it also removes the problem of the front end bottoming out when you f*** it up and hit something hard because you weren't looking where you were going :unsure: you have to hit something really v hard to bottom the front out with rear springs on.

Basically I think I will measure the ride height, fit these, measure it again and use it for a bit to see what it is like, since it isn't costing me anything to do it. Another option is to refit the original fronts but get some +1" or +2" lifters like Mill Services supply, but again those are a few weeks away.

JST - thanks for your offer but the cost of shipping them down by air would be as much as buying new springs :(

Here is a pic of the old red 90 with "rears on the front" and "rears plus 1" lifters on the back" - 33x12.50R15 tyres.


Looked about right to me, steering was OK on road, didn't chew up UJ's and didn't bottom out. The only thing I had to change was the rear shocks for the slightly longer 110 type but with these new Monroes being much, much stiffer than std I think the "topping out" on the back should be minimal.

PS do not swat a fly in the middle of your monitor, like I just did. It makes so much mess and then smears everywhere when you try to wipe it off :unsure:

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Further on this, I just checked the spring rates of what Tony is using (OME 764/781 F/R) and they are 240lb and 290lb!

And theres nothing wrong with that.

It will give a stable truck, the bump stops will not be visted every moment you gop too fast, you can load god knows what in the back and have a great "Carry" truck, but, it won't do this :


1st test of some rear suspension mods, well chuffed and more to come yet, I am aiming for a 90 that I can heavily cross ruts and the spring will give and the bodt stay level(ish)...

However, I will not have a 90 that I can shove weight in the back, and the bump stops will definately not be lonely :lol:

So far quite please, front is next and some softer springs for the rear


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Sorry Tony, wasn't aware it was supposed to be a secret! :unsure:

I have done the swap now and it now sits very slightly higher at the front than at the back:


front bumper height off the floor has increased by 55mm passenger side 66mm drivers side (soon level that up when I get in though :P ) and as I reckon it was a good inch lower than std with the old springs plus the winch, I guess that should be about an inch above what a std non-winch vehicle would be - just about spot on.

Need a tweak at the back as well but I think HD 90 rear springs would be too solid so I think a call to Mill Services might be in order - those are light enough to come by air so will be here in a couple of weeks.

I do like these Monroe gas shocks - they felt really stiff when I was pumping them (ooer) and I thought the ride might be a bit choppy but it's really good - I walloped it through a few holes that will bottom the Discovery front end out and it hardly noticed. They were a silly price from Bearmach too - landed here they only cost about the same as std LR ones :)

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I have as you know seen your 90, ...........and know it will articulate as per the photos.

Springs and spring poundages are a F nightmare.

It is (as all things 4x4 are) a compromise................

What you have I belive gives you some lift, ...........when you lift a 4x4 the COG goes up, ...........and can make springs that are firm seem like jelly, its all to do with levaerage.....so for lift poundage has to be considered

Some people fit longer springs for lift and then find it handles oddly, yours is a "Classic" set up, .....and one that for the money is hard to beat,........ it can have knock on effects with things such as COG and caster, but you've fixed these, .............many don't do it .........and have a 4x4 that frankly is missing the suspension mods 'finishing touches'.

You also have a 90 that can carry loads, and with the lift it will articulate, ....but will do it when pushed, .....as oppossed to at the drop of a hat.

Suspension mods have given me a headache trying to work out what I am after, ......far sillier thinking time than the route you have gone ...........but it is a different route,.

If you look at the supermods around now and the american rock crawlers etc the springing is often so soft and long travel as to be almost undrivable on the road, .............the idea being that a obstacle is met with the axle moving immedaitely , and the body staying put and level, the problem here is that go a tad too fast and the thing just bottoms out on everything.

What I am trying to get to is a compromise somewhere in the middle, ....soft soft springs, .....and long so they don't disclocate so much (The ones I started with at the movement in the pics woyld have been 3 inches from the cones, these were still touching, so the ground dtill has pressure from the downwarsd foerces of axles and springs etc......but now 'spring bind' has reared its head !, and I have plkans for an extra 2 " droop and rise, just need to make some top mounts and rethink springs again , ......and this is just the rear !

I start V soon on the planned front suspension mods ..........

3 link would be best for articulation ..............but again I use it on the road and 300 bhp and 3 link ?,

so compromise (and loads of thought and research ) is the order of the day, and will this be plan A B or C D E etc before I get what I'm after.....

Hopefully when I get there the axles will move at low speed with huge movement (A Frame ball joint locking is now coming up as a problem), but I will have to do this at low speed, and as you may have twigged this so far is now on the rear only ....and at plan C, .....plans A & B for the front already consigned to the bin.

For what I am after I think your set up would cause me 1 BIG problem -

it wouldn't fit in my garage !,:lol: ...............

........... but in all seriousness TCs set up is a sound easy simple well tested and quality route and will save a fortune on research and asprin, I am just trying to get the a similar end in a differnt way if I do indded get there, who is to say whos got it right and why ?

Better ?, .............no

different .............Yes,

it all depends what your after.........and if you can indded get it !


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Hi Stephen

How much is the back down by? If it around half an inch you can fit the Range Rover rubber spring isolators on bottom of spring. If it's more like an inch you can fit them top and bottom :) They are cheap, about a fiver and light to ship too.




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How much is the back down by? If it around half an inch you can fit the Range Rover rubber spring isolators on bottom of spring. If it's more like an inch you can fit them top and bottom :) They are cheap, about a fiver and light to ship too.

Good suggestion Steve: but already on there :)

The previous owner fitted them to the back springs to cure a boingy spring and I put a pair on the front springs this morning - I've used them on previous vehicles and they do seem to reduce the amount of road noise.

I was just waiting for somebody to say something about that shocker..... :P no comments about the nuclear explosion outside the window then?

The new ones are a rather loud shade of yellow :ph34r:

back ones were bluddy hard to get on too - the amount of gas pressure in them is huge and I had to sit on it to get it to go down then quickly zip in underneath and fit it before it extended too far - I couldn't compress them lying under the vehicle, too strong. Took four attempts on one side, and I bashed my head on the trailing link trying to get under the vehicle while the rapidly extending shocker was trying to insert itself up my nose :rolleyes:

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I am aiming for a 90 that I can heavily cross ruts and the spring will give and the bodt stay level(ish)...


Jeez ..... I suppose thats cause you don't want to spill your coffee :lol: ...... aiming for a soft ride :blink:........ do I detect old age creeping up on you Nige ?:lol:............ if you want to keep the body level [has vision of Nige traversing metre deep ditches with a spirit level on the dash] .......then why not go over to ultra long Fox shocks with coil overs :P ?

Whilst on the subject of springs, like Tony, I also use 781 rears / 764 fronts( that coz we shop at the same place and its a proven combination). On the truck cab this gives me about 2.5 inches of lift. However, I think Tony is using OME Nitro-Charger shocks, whereas I am using Pro comp +2inch.


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