What holds the upper spring isolator in place.

[Morphyne]

Doing a Rear Air Suspension delete and I have everything put together on one side. It looks like the upper rubber cone (spring isolator) just sits in the groove in the top?

 

[TowMeOut]

From what I remember when I swapped in my FJ springs, there are no fasteners. The rear bumpstops (cone pieces) are just sandwiched between the spring and perch area.

 

[f250ben]

From what I remember when I swapped in my FJ springs, there are no fasteners. The rear bumpstops (cone pieces) are just sandwiched between the spring and perch area.

Correct. Replaced my rear suspension a couple of months ago, OEM springs come down out below the perch, with the spring isolator just sitting on top.

New springs or old OEM springs are installed with the isolator sitting on top the same way. No fasteners or anything.