Please can someone answer this question? Why is there a squeak from the rear of my car suspension in dry weather.

It's the handbrake.

Nope, really, it is!

At the back where the squeak is coming from (usually the right) there is a rubber grommet with the handbrake cable, spray some lithium grease or similar on it, and that will sort it.
Mine has been fine for at least 3 months since I did it.

A bit of searching will reveal some pictures if you have issues following my crap description.

You do not need to jack the car up, but it will be easier for the first time to see where it is. Don't need to remove the wheel though.

My Rattle comes from the seatbelt roll on the left passenger side, vibrates, managed to stop this by puttin an old t-shirt up in the gap ha

I swear my spare wheel is the source of my squeak.... or maybe I have a mouse?

i wondered this if it could be the spare wheel, might check it out.. IF the dreaded squeak returns

I had this annoying squeak and mine was the gromet for the handbrake. Had mine sorted by Ford and havent heard it now for couple months.

handbrake cable for me too. ford fixed it when i went in and said it's not spare wheel and not parcel shelf and i thought it was handbrake after being on forums.

Also, Ford seem to be a bit confused as to what it is, from what I have read.
They seemingly quite often grease the actualy cable - it is not! It's the grommet itself.

Too many baked beans?

lol, does the handbrake cable squeak sound like its coming from under the rear passenger seats?

I would say it sounds more like the suspension - but possibly.
It's kinda like a 'chirping' that is worse over slightly bumpy surfaces, but generally goes constantly...

yeah that sounds about right i just fixed one squeak then another one pops up, do i need to grease summit do i? a DIY job or garage jobby??

I used a spray on lithium grease, and that sorted it for the 4 months before I sold the car.

WD40 seemingly works but is a lot more short term (you would potentially be re-applying it weekly).

im gettin a squeak mainly when going over bumps on the road sounds like its coming from somewhere under passenger seat

Ive got that same squeak Alan
where would i need to spray?