expand UFS partition

I have a UFS which is near full, and I know there is spare/un-allocated 
space on the hard drive.
I can not back it up first , as it is both huge and very busy.
Are there any tools within FreeBSD to (a) examine if expanding this UFS 
is possible, and (b) expand it reliably ?

I have gparted, and could run it. Which would involve bringing down the 
server for that duration.
All fine & dandy... but can I trust gparted to not wreck this task ?

A back up first would take the server down for several hours. I cannot 
take it down for that long.
Now, if I wreck the drive, hind-set would have kicked me square in the butt.

I suppose that I could test the reliability of this task on a spare 
server. And likely will.
Unless, that is, FreeBSD has a built in ability.

Also... old FBSD .. 11.0 p1 ! ouch
Thanks !

-- 
Jim Pazarenafquest@paz.bz
Haida Gwaii - British Columbia - Canada