Series 3 spring measurement

[jad]

Hi guys, I am thinking about replacing the springs on my 109 for parabolics. I am looking at GB springs and there are a couple of options due to load rating. What I am trying to understand is if my truck is at a normal ride height on the front or if it is lower due to spring sag or the way I have converted the coil axles to leaf springs. The rear has a good distance between the bump stops and axle. The front looks closer than I would expect although the tyre to wheel arch looks normal to me... Could anyone with standard springs measure both the bump stop to axle distance and bump stop to the bottom of the spring mount/top of spring. Both of these measurements at the front of the axle as pictured. Mine is ~44mm and 175mm on the driver's side and ~48mm/180mm on the passenger side. So a little lop sided.

Thanks

Jad

[lo-fi]

The measurements you want are in the BGB. Measurements from vehicles are going to be worse than useless as you don't know how much the springs may have sagged, whether they were to spec to begin with, if the bushes are worn or a host of other little factors. 

[jad]

Excuse my ignorance BGB?

 

Thanks

[lo-fi]

The workshop manuals are big and green

[jad]

Shouldn't it be BGM then?

[lo-fi]

Big Green Book, but yes. You can find in PDF online, but it's worth buying. 

 

[jad]

Thanks mine is at least 20mm low at the front and back then. Bushes haven't had significant use they were put in so shouldn't be too bad so the other variable is the leaf spring conversion and spring sag. If someone could measure the depth of their axle from spring seat to bump stop that would be really useful.

 

Cheers

[Snagger]

You will have lost some height with the axle conversion.  The amount is just the extra height of the saddles that sit on the springs compared to the normal saddles on an original axle.

Dont forget that the bump stops on the top of the axle are also taller than the originals, so the gap between their top and the rubber lock is pinched twice.  It really is worth shaving every bit of pc those modified saddles and bump stops that you can to retain  ride height and articulation that is possible.
 

 You could consider using 1-Ton front shackles and rotating the springs down a little at the back - it’ll make 35-40mm difference at the back, so about half that at the spring centre.  It would mean resetting the saddle angles, which could be done by shaving their faces with a grinder and fitting a new face plate to locate on the spring dowel, rather than starting from scratch, but it is important to retain the axle’s swivel castor angle at 3 degrees.  It’ll also increase the chassis height and suspension articulations gap that bit more.