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The only place for a coil spring is up Zebedee's arse
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My Monroes are good, IMHO. I have front and rear. As mentioned on. net, i don't trust people re-selling "OEM" stuff and who think you don't need/ deserve to know the manufacturer, especially on a pair of shocks. I'd rather have a name, and know who to blame if it turns out to be shite, although thus far I trust Bearmach as an umbrella brand, even though obviously they don't manufacture all their stuff. But in this case (ie P38 shocks), by the time you've priced up a Bearmach set you may just as well have Monroe.

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Glad to hear that the Monroes are good.

However after (too much!) mimbling I've decided to go for a set of Bilstiens from Paddock. Twice the price of Monroes but half the price of genuine Land Rover parts. With any luck I shall be able to report back on how they do in a week or so.

Clive

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Got the full set of yellow Bilsteins from Paddock. Including the steering damper. With a couple or three hundred miles on the clock preliminary assessment is that they are stiffer than what came off and more progressive. Damping increase with larger suspension movements is noticeably more aggressive than standard.

Which may annoy the living daylights out of me when I finally get things sorted.

Its still not right. Stiffer damping seems to be covering up the underlying problem.

If it were conventional car with metal springs I'd say the symptoms point to worn out way too soft springs. But I don't think that's possible on a P38 as spring rate is effectively set by the pressure in the air bags which in turn is defined by the ride height. Way I see it so long as the car can hit and maintain the right ride height there must be enough pressure in the bags. Certainly my three amigos are behaving just fine and waving the tape measure around between arch and wheel centres suggest its about right. A little high perhaps on standard, maybe 1/4 - 3/8", but I'll sort that next time I can get on Mikes nice level barn floor. Best part of my drive puts a canter wise tilt of about 1" across the car so I guess thats close enough for the spacers to work just fine. But its so much easier to play with spacers with a chassis lift instead of futzing with a jack doing one at a time.

Steering isn't happy either. Seems to have picked up a bit of play in the system and car doesn't wan't to run dead true. Time to get my steering box rebuilt so I know I have a decent one fitted instead of that second hand one of unknown history. Local(ish) land Rover guy can get it done for £350. Lot more than the E-Bay exchange mob but it will be the full monty not a wash'n seal jobbie. If I'm going that far hafta wonder if it makes sense to dump a fat £100 into an OEM steering shaft too. I know I tend to dump more money into new parts than most folk but at least then I'm pretty sure it will be right.

Clive

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The spring rate for an air bag is determined by the profile of the piston part at the bottom. The elasticity of the rubber bladder doesn't set the spring rate. It is the piston going in and out. The air pressure just sets the ride height.

For example, I fitted Arnott Gen III's and, because the piston is machined with a different cross sectional area at each ride height, it has different spring rates compared with Dunlops. They are harder on the motorway and at std height, yet softer off road. Anyway I digress.

Tyre pressures for standard tyres should be 28F/38R. It is very important as I have found and I am running General Grabber AT2's.

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To be nit picky, the volume of air, not pressure, sets the height. The weight of the vehicle sets the pressure.
I'm also running Gen 3's, and I really like their spring rates, less body roll when cornering on road, and a smoother ride on the rough.

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Air springs are complicated. I have an inch and a half thick textbook somewhere that barely scratches the surface.

Anyway mine is on standard Dunlop airbags about 20,000 miles old so they should still be behaving fine. What I don't understand is why it has started behaving as if the springing is too soft. Looking back it started misbehaving about 1,000 - 1,500 miles ago and has steadily got worse. Putting the stiffer Bilstein dampers on has done pretty much what I'd expect from trying to control over soft suspension on a steel sprung car by uprating dampers instead of springs.

No leaks. It stays up for over a week when parked and pretty much never takes more than a few seconds to sort itself out ready to drive off regardless of load. Unless I park in just the wrong place with the left hand front wheel in an annoying dip perfectly matched to the tyre radius.

Clive

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Probably a silly question but.. how are your roll bars/bushes?

edit: it was a silly question - you've already changed the bushes and links.
Only the bars themselves to go then, but I've never heard of them wearing out/going floppy

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Harv said:

To be nit picky, the volume of air, not pressure, sets the height. The weight of the vehicle sets the pressure

Yes, you are right Harv. That is a better way of explaining it.

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Clive, I would forget about the General Grabber recommended tyre pressures and stick to the factory 28F/38R.
Are you on 255/65/R16 tyres?
May not solve all your problems but should be an improvement.

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Searched for "wallow" and read this thread with interest as it more or less echoed my own thoughts.

Clive - did you ever make any further progress, or reach a point you were satisfied with?

I've done much the same as you had when you began chasing this - new air springs all round; new radius arm bushes at the front (as you know!); new anti-roll bar bushes and links; new panhard bushes at the front; new shocks (though they are just Britpart oil filled ones). I'm getting a very unsettled feeling from the back of the car - even with no passengers!

On my list to do are: trailing arm bushes and rear panhard bushes; and following the same logic as yourself, changing the rear sensors as I know mine are pretty knackered.

I might be lucky and find this sorts me out, but just wondered if you tried anything else?

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Rear panhard rod bushes would unsettle the rear if they're worn, I have the BP shocks and find the find very supple and the handling superb.

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Been at the "OK, sort of" level for the past year or so.

But I'm thinking I may have under estimated the effect of tyre wear, and age as they are over 10 years old. Been getting the odd kick of anti-lock in the damp this year and Mr MoT man agrees with me that the tyres are coming up to their sell by date so this months pension will have to stretch to four new booties.

Currently researching to decide on a good 16" fit for road use. Local tyre man wants to sell me some Yokohama boots in a slightly off beat size and minimalistic tread pattern. Which isn't going to happen however good he thinks they are. Right now I'm tending towards Michelin Latitude Cross or Goodyear Wrangler as the tread patterns look effective without being off-road aggressive.

Amused to see that both Michelin and Goodyear have a C wet grip rating but the Goodyear claims to be specially developed to be good in the wet. O-Kay! Looking at the pictures the tread pattern on Mr Goodyears offering looks to be "bog standard for the last 40 odd years ever since they figured out snipes". Cynical moi asks "So where did all the development effort go.". Which may be good thing given how much a P38 doesn't have connecting the round rubbery bits to the car.

Asymmetric tread patterns always seem to me an invitation to the sort of issues that eventually lead to the death wobble.

Fundamentally modern tyre designs expect to see strut, or even wishbone, front set ups with the wheels moving in vertical arc controlled by relatively short links. Our rigid axles holding the wheels mutually upright put a rather different set of forces on the tyres under bump or roll which a tyre expressly designed to handle the (slightly) opposite and arcuate motion of independent front suspension may not cope with well.

We shall soon see.

Clive

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I've recently fitted a set of these https://www.mytyres.co.uk/rshop/tyre/Kleber/Citilander/255-65-R16-113H-XL/R-279885 to mine, admittedly in the 235/70 x 16 size that my 7J wheels need and have no complaints and they are an All-Season tyre rather than a summer tyre that the Michelins are. Kleber are actually the budget brand for Michelin anyway. I've had Goodyear Wranglers in the past and they are pretty dire in the wet or anything other than smooth, dry roads. I then went to the Vredestein Quadrac but they are no longer available in my size so went for the Klebers instead.

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Mines on Michelin Pilot Sport 4's and doesn't exhibit any weirdness despite it being a very modern tyre design.

I guess it depends if you actually need an all terrain tyre. Mine spends basically 99% of its life on tarmac, and I'm not up for ruining that handling in exchange for some off-road grip I use once in a blue moon!

I've done some very light offroading with the Michelin's and it was fine, I doubt they'd deal with mud ofcourse.

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I'm much the same, 99% road use with the very occasional climb up a mountain where traction isn't a problem but grunt is and also the the odd time on snow. To get to the snow requires a long drive to the in-laws so good road grip, comfort and low noise are my priorities. The Vredestein were really good and the Klebers I'm on now seem to be very similar.