After renewing all front suspension the front end drops after 20 miles what could it be 

a bit more info required 

did you replace with like for like parts or a lowering kit ??
what parts where actually changed
how far dose it drop 
 

2 minutes ago, Phantom76 said:

a bit more info required 

did you replace with like for like parts or a lowering kit ??
what parts where actually changed
how far dose it drop 
 

All for like for like

what parts ? and was it on both sides ?
 

 

3 minutes ago, garrysnook said:

All for like for like

Drop link arms strats springs anti rollbar bushes bottom wishbone arms 

2 minutes ago, Phantom76 said:

what parts ? and was it on both sides ?
 

 

Both sides 

did the top strut bearing go back on in the correct position 
are the springs the same size 
are you sure your not overthinking things with a whole new front end the car will feel a lot different than before 

2 minutes ago, Phantom76 said:

did the top strut bearing go back on in the correct position 
are the springs the same size 
are you sure your not overthinking things with a whole new front end the car will feel a lot different than before 

Every thing went back OK only thing I can think is the antiroll bar not holding right do you think this is the problem 

Springs do settle a bit over the first drive.  But if it's not that then there are only a few things it can be:

Snapped spring due to manufacturing defect (seems very unlikely on both sides)
Springs shifted into cups if not seated correctly when fitted
Struts dropping if not fully inserted into hub when fitted
 

i personally would start at the spring and work your way back to see if anything shifted loose, then this is a shot in the dark but the anit-roll bush sits on top of the wishbone bush and the bolt goes thru both, make sure the anti-roll bush is actually seated properly,

do you get any knocking noses or other symptoms 
did you have it tracked ?

Knocking when going over bumps in the road both springs are new and seated properly 

And it just passed its mot 

Passed MOT since the drop?

Something weird going on here.  There are only 2 things that determine the ride height.  The length of the strut between the hub and the lower spring plate.  And the length of the spring when partially compressed by the weight of the car.  If both spring and strut are fitted correctly, there is no way they can drop.

The ARB should be able to move up & down in it's bushes.  So while it could push the chassis upwards compared to the struts initially with very tight bushes, that should have settled to the correct level within a mile.  It should also been tightened with the suspension loaded to prevent that happening anyway.

Check the strats and they both sitting as they should so only thing I can see is the antiroll bar lost its tension  may be I'm wrong but that's the last thing I can see

top mounts are not in the correct position, did you make them when removing old and lineup the new 1, or just put it on and tighten up

All lined up perfectly from the top to the bottom 

 

22 hours ago, TomsFocus said:

There are only 2 things that determine the ride height.  The length of the strut between the hub and the lower spring plate.  And the length of the spring when partially compressed by the weight of the car.  If both spring and strut are fitted correctly, there is no way they can drop.

Tom's post states what determines ride height.

On 4/27/2024 at 11:24 AM, TomsFocus said:

Springs do settle a bit over the first drive.

 

Is it actually running lower now than before you changed anything ?

When you lift a car with struts and track control arms/ lower arms, then lower the car, because of the droop whilst lifted, the wheels will not be in the normal rolling position, so the car will sit higher until you have driven it.

 

Are they Ford parts ?

 

When driven the anti roll bar hits the bottom wish bone arm  if you go over any bumps or potholes on the road

They are all ford parts  but after running car for a mile or two the front end gets to low to the ground every bump or speed bump it bottoms out and bags 

About to give up on the car

Sorry, I still can't understand what's physically happening here.

The ARB shouldn't be under tension on a flat road.  It only gets tensioned by body roll when the car leans to one side.  You can unbolt the drop links both sides and do a short test drive without the ARB connected to rule it out.  Just take care not to push it too hard into any tight bends.

If we can rule out the ARB, then maybe the springs are getting weaker as they heat up.  Are they definitely Ford ones?  No chance of them being fakes in Ford boxes?

2 hours ago, garrysnook said:

They are all ford parts  but after running car for a mile or two the front end gets to low to the ground every bump or speed bump it bottoms out and bags 

Could you take some photos of the parts and suspension items so we can try and understand what is happening ?

Surely it can only be strut length being too short, or spring length/rating.  Even if the drop link mounting on the strut is in the wrong position, I cannot see it altering ride height, but may account for the banging.

What engine does your car have Garry ? @garrysnook

12 hours ago, Paulkp said:

Surely it can only be strut length being too short, or spring length/rating.  Even if the drop link mounting on the strut is in the wrong position, I cannot see it altering ride height, but may account for the banging.

Unless I'm reading it wrong, it's sagging each time it's driven, but ok again at the start of the next drive, which adds even more confusion.

I'm almost certain it's nothing to do with the ARB.  And the strut length could be wrong, but can't be changing over a drive.

Damper gas volume could be changing with temperature, but shouldn't set the ride height, and if anything I'd expect it to expand and increase the damper length when warm, rather than decrease. 

So the only thing left is the springs sagging when warm.  But I'm not sure whether they'd regain height as they cool down or not.  If the springs are sagging, they could be for a lighter engine or vehicle.