What does bolt-on kit actually mean?

Front of Shiny Black Mercedes on Air Suspension
4 part full air suspension kit
front air suspension fitted to car

Like most air suspension specialist we sell a lot of kits, and we also sell a lot of bags. On occasion a customer will come back to us and say that they have a hole in their bag because it touched on something. Most customers are sensible, viewing it as an expensive learning experience and realise this is not a warranty issue. All manufacturers state clearly that it is the absolute responsibility of the installer to ensure that at no time can the airbag ever touch or even come close to metalwork. The result of not checking or taking action to avoid this is inevitable - a hole in your bag.

What can you do to avoid this?

Put simply - most kits require a clear 1 inch gap around the bag to be guaranteed never to touch. This is because when you go over a bump the pressure in the bag increases dramatically for a short period of time and this will make the bag wider for a short time. So even if it is clear when static it may not be under driving conditions. Secondly on front suspensions with McPherson struts you will find that they turn - sometimes not through the angles you would predict, which can make the situation worse.

If you have the clearance then you wont have a problem. Again its quite simple - bits of metal that could touch may need to be removed. On the Jaguar kits you can simply pack out the anti roll bar with washers for more clearance. Rear driveshaft's and gators can also be an issue - sometimes smaller diameter gators are available or the kit must be adjusted to clear. At speed gators get larger too!

How can this happen on a bolt-on kit?

A bolt on kit just means the kit bolts onto the vehicle - as opposed to a weld-on or fabricated/universal kit which will need a lot of work. It does not mean that the bags cannot touch, or that you don't have to do any work to make them clear or that you can close your eyes and never verify all is good. Wheels are bolt on, but when you modify a car and fit larger or smaller wheels it is down to the installer to ensure they don't catch on the arches when going over bumps or turning corners - that's what bolt-on means. You should not need to fabricate or modify the kit to fit, but you may well have to modify the car for it to fit - same as wide wheels/tyres.

Some of the kits we sell for older vehicles - such as Mercedes from 1960's to 2000's, The Jaguar XJ40/X300/X308 kit, Classic Mini and Ducato front struts all have very tight clearances. Some need small parts of the chassis to be cut away or a redundant bumpstop perches to be removed. All are bolt-on kits. Most modern vehicles have different suspension and its far less likely to be an issue, although some Hondas require the front arms to be shaved a little.

So what can you take away from this note - if it touches it will fail. Its not a matter that "it will be ok" - it will never be ok - more a matter of when not if.

Any questions? Call us on 0800 772 0315 or send an email to ENQUIRIES@AIRRIDE.UK