15 inch rims for Series III LWB for softer (less harsh) ride

Hi,

I am doing a rebuild of a 1975 Series III LWB soft top, and whilst trying to keep as near original as possible, thus I want to keep standard leafs etc. one thing I remembered in the past was people fitting 15 inch rims to a series to give it more softness... note, this is a standard 2 1/4 diesel so performance is not an issue.. (or lack of it.. so anything above 55mph will be lucky....) I am not intending to do any serious off-roading, as I have my modified Disco1 for that... I just want a Series to run around town, to the coast etc. at weekend (and occasionally tow my boat a short distance..), so want a wheel and tyre that is the same overall diameter as standard, but a bit softer ride... thus I also assume a softer tyre sidewall etc. rather than something like the BFG MT's I have on my Disco1 that are very stiff.... and have successfully managed to destroy the original Discovery ride quality....

So my question is..... for the softest (least harsh) ride on standard leaf springs would it be advisable to go for 15 inch rims and then the ideal tyre size for standard overall diameter, but softest sidewalls.

or should I just stick with the standard original 5.5x16 rims and then fit normal Avon Rangemasters?

I get your idea, but I think there may be some issues. The bigger tyre will give a softer ride, its the first contact with the bumps and has low interia (only the tyre has to move, not the tyre, wheel and hub) so the idea has potential. But I think there are problems, they may not be insurmoutable, but they could mean you don't get the better tide you had hoped for:
Series 16" tyres are already tall by modern standards - ie 7 to 7.5 inches so while you will go up 1/2" (half of 16-15) its not a big change.
To keep the same rolling radius the tyre will get wider - if you are aiming for a 32" OD a 15" tyre will be around 8 1/2" to 9" wide if its 100 profile of 10" or more if its /85. Noise will go up, turning circle down.
To get a better ride you want the sidewalls to flex, which means a lower tyre pressure, but on a bigger tyre you need more pressure to keep the tyre hard so it tracks in a striaght line, otherwise it will wander all over the place.
If you think about off road a large low pressure tyre is great, but on the road its a real handful unless its pumped up. If you do pump it up enought for decent striaght line driving my guess is it will ride pretty much the same as the smaller tyre.
Don't forget as tyre width goes up so does the kick back on the steering and that can be hard work
I do around 3-5000 miles a year in my Series and its on 235/85 16. What has helped the ride?:
Getting the TPs right - some sidewall flex but OK stablity.
Oiling the springs, and oiling and oiling then wrapping to keep the oil in.
Weight so the springs get inot thier bendy range.
Next job, better seat padding.
I would do those first, you can get some nice 15" LR alloys and tyres off e-bay quite cheap, but my concern is that they don't give the improvment you hope.

Wot he said ^^^^ above.....


Leaf springs only work properly if each leaf can move independently of its neighbours - so I'd be splitting them, cleaning them up, and re-assembling full of grease. Then, of course, they'll need wrapping to stop sh*t getting in....

Thanks for the replies.... yes, I see your point about the width.. and with the narrow track of the Series and tyres rubbing on the springs... so best to keep to normal width. and as you state, about greasing the leafs etc. and some better foam in the seat base... and a bit of weight in the back....

It's been now 28 years since I last had a Series on the road...... having been on coils (90, RR Classic, and Disco1) since then...….. the idea is to at least keep the Series as standard and original as possible... (i.e. nothing major that cannot easily be returned to standard...)

incidentally my very first Series Landrover is STILL on the road according to DVLA.... it was KFP 469K...

Oiling the spings can be a bit of a revalation, they will never be soft, but they will give a reasonable ride with a bit of load. They just never cope with speed humps, I think its because you hit both wheels at the same time and the whole axle has to shift.

I think this idea came about years ago when most of the available 16 inch tires were crossply and 15 inch radials were more widespread.
Best set up [ for mostly road work ] I had on a 88 petrol was small lorry radials,standard front springs with lwb shocks,lightweight rear springs with standard shocks all well maintained.

31.10.50R15 used as a standard size in the USA.

How many leaves are in the spring packs? Can you remove a leaf or two?

tottot said:

Best set up [ for mostly road work ] I had on a 88 petrol was small lorry radials,standard front springs with lwb shocks,lightweight rear springs with standard shocks all well maintained.

Click to expand...

Standard shocks are nearly always the best option - "they" spent a few quid working out which ones to use .....

Once you've got the springs working properly, It's worth checking and probably replacing all the shocks ....

The series has a comfort setting mentioned in manual dropping the rear psi from 30 to 25
I have the rangemasters fitted but not checked the pressure since installed and with standard cleaned and greased springs the ride is quite reasonable

The trick is to stop the 'Big girl's blouse thing' and drive it.

25-28 psi (most over-inflate) , motorcycle chain spray into the springs and drive it. Most often leafers are left un-driven so the springs bind-up. Sometimes they break when you eventually move 'em. Drive greased springs 3-400 miles and drive daily hereon in. Keep greasing. You'll see real improvement. If it's not going to be driven, you'll never get to that point, and if you do, you'll not keep it there. The only real solution is driving it

Sorry... it's a leafer.

I'm now drviing my series pretty much daily and a whole load of things now work better than they ever have. There were a few things that gave up when first called upon - the output and hub oil seals, a rad hose, the fan belt, but most everthing now works better than it ever did when I was only using once every few weeks. The brakes no longer pull (or I'm so used to it I don't notice..) the wiper parks and the heater heats (shock and awe) and even the oil leaks have reduced, I'm assuming that the seals are staying softer with use (and that there is oil!!)

I absolutely agree with the above, series that are used regularly become much more civilised after a while, especially the suspension. I've never really bothered oiling or greasing my leaf springs. When I first got it, it felt like there was no suspension at all but now it's much better, I still have to brace myself for speed bumps. Some of the improvement is down to the driver getting used to the vehicle, after a while you don't notice how heavy the steering is or how noisy everything is. But, I took my wife out in it for a spin and she was surprised how much better it was compared to the first time she went in it, she doesn't go in it very often and I don't encourage her to either, she moans about the cobwebs and mouldy sun visors.

Col