Bottoming out

[aaronflint1592]

Hello people

I hope your well. I need a bit of advice.

When I bought my van it had been lowered. Soon after I bought it I discovered that its suspension is bottoming out when I go over a bump. When I mean bottoming out I mean spine shattering thumps. What do I need to change (I'm thinking I'm going to have to change the shock absorbers???).

Regards
Aaron

[AdrianC]

No, the springs (but probably the dampers, too)

Springs absorb the shocks and wheel movement. Dampers ("shock absorbers") merely stop them bouncing around afterwards.

I suspect you'll find that it's been lowered by chopping a coil or two off the old springs. Springs are rated by a certain amount of weight per measurement compression, spread evenly across all coils. Chopping a coil or three down will only reduce their stiffness, so they'll be softer - whilst what you need is harder, because there's less travel available before the bumpstops. Since they've pikeyed that, they've probably just left the original dampers on, which aren't going to be suited to shorter, stiffer springs. Or, even, shorter softer ones...

[California Dreamin]

Depends on just how low it is as to whether the original dampers would have the range of movement or as many are...very close to sitting on the bump stops (a rubber buffer fitted to the damper rod).
This bump stop is usually shortened to allow a little more 'stroke' from the standard dampers but there comes a point where the standard dampers are just too long and need replacing...like I say, depends on how low.

Martin