knocking over bumps

[Rust Bucket]

Evening all

I've lowered the van (1990 td converted panel) by 45mm and it has developed a knock when going over bumps on the n/s front, the spring is seated correctly and i've doubled checked all the bolts anyone have any ideas?

Thanks in advance

[California Dreamin]

Standard shocks bottoming out? bump stops cut too short? broken anti-roll bar drop link? worn out anti-roll bar mount or link rubbers? shock absorber failure? excessive top or bottom ball joint movement? track rod end excessive play?
Basically anything excessively worn on that side.

Martin

[Rust Bucket]

put new shocks on, cut 3 ribs off the bump stop, anti roll bar and bushes look ok, going to get the track rod ends replaced and geometry setup.

Could the upper wishbone bushes be causing the knocking?

thanks

[California Dreamin]

put new shocks on, cut 3 ribs off the bump stop, anti roll bar and bushes look ok, going to get the track rod ends replaced and geometry setup.

Could the upper wishbone bushes be causing the knocking?

thanks

The top wishbone rubbers are a weak point on these vans and do fail at a high rate. However, they don't normally cause a knock, the common symptom being a very anoying low speed squeak over bumps.
Wishbone bush failure is easy to see: look from the front at the end of the pivot bolt and if it is desernably OFF center (not in the middle of the bush) they have very likely collaspsed.

Martin

[Rust Bucket]

Cheers bud

I think i might do a complete overhaul of the front suspension bushes as there probably still the original.