Unimog Club UK

The standard suspension on the Mog is designed to cope with the weight of the radio box so is quite stiff.  Now my radio box is no longer there I need to find a way to help the suspension flex.  My initial solution was to remove the rear inner helper springs and put a load of ballast in a box at the very rear of the chassis.  While this certainly helped it did seem to make the rear prone to sliding on side slopes.  I am guessing having 150kg of weight trying to head down hill will have that effect  :lol: 

I needed a plan B and decided to swap the springs.  My goals for the swap were to give it a slight lift (I have some 39" tractor tyres sitting in the garage    ) and also make it much easier to flex the suspension.

First task was to remove the rear springs.  Very easy to do, they are secured top and bottom with loads of access.  I did not even have to remove the wheels, just removed the clamps, removed the top damper mount and jacked up the chassis until the spring came free.

Old spring against new



Popped the new spring in, refitted the clamps and lowered the chassis.  Left the damper off at this stage.

Next stage was to remove the front springs.  Same principle but this time I had to remove the wheel for access to the top clamp.

Old front spring (short) against old rear spring (long)



It was harder to get the "new" springs onto the front and I had to resort to using a pair of spring compressors.  Easy from then on.

Now comes a bit of a health and safety nightmare.  I wanted to see how much flex I now had but don't have a big ramp to drive up.  Resorted to piling a load of weight onto a rear corner and jacking up the opposite front corner.  Problem one, my jack does not go high enough.  Solution (close your eyes if you are of a nervous disposition) was to balance an axle stand on the jack and then jack it up.  The reason for this test was to work out what I had to do with the damper mounts (remember the dampers are still disconnected).  Here is the resulting walk round.



The results showed me that I need to drop the rear damper top mounts by 3.75".  I have made some plates to this but don't have any pictures at the moment.

For those interested in figures, with the old springs from the ground to the centre of the wheel arch was front 1110mm and rear 1120mm.  With the new spring arrangement it is front 1155mm and rear 1155mm.  So the front has gone up slightly more than the rear but nothing too bad.

Using spring rates and free \ fitted measurements I have worked out that each front spring is holding just over 500kg and each rear spring about 240kg.

I am going to an off road event next weekend so will see how it now performs.