I don't have any advice to offer as I'm a new Jade owner myself, but I would love to see a pic of ur tree. I do believe they like their roots to be "snuggled".

You're going to need a team to repot that tree! You definitely won't be able to do it alone. At least one or two other people to help you. I don't know what it's potted in now, but if you are unfamiliar with the type of soil to use, you should be using coarse, fast-draining soil. I use cactus and succulent soil and mix it with perlite (you can find both in a nursery). C+S soil, although better than regular potting soil, is still not fast-draining and coarse enough for jades and other succulents. I use 2/3 soil to 1/3 perlite.

Other than that, if you have a 5 foot tall jade that looks healthy, I'm sure you know what you're doing! If this was a gift or something passed down to you, then some basic things to know is that jades like lots of sun, and be very careful not to overwater. Don't pot it up too big...only go up about a size or so (what size is it in now?). I have a jade that's about 3 feet tall with many trunks...it's in a pot that is 18" in diameter. I typically water my jade no more than once a month (sometimes even once every two months) in the colder months, and once every two weeks in Spring and Summer.

I would love to see a picture of your jade also.

Gabi

I would go with a large pot  the larger the pot the faster the growth. I have a couple that size  I use 25 gallon containers. You may need to prune it with repotting &/or you will end up with a bunch of cuttings.
When growing large jades my advice is to go for trunk strength rather than height. Otherwise, they can topple & are weak. As they age a weak trunk can fracture due to the weight of the branches. To get a strong trunk, prune it down.
You may need to stake or support the plant until its roots take hold in the soil. Or, plant the trunk a bit deep.
Avoid washtub containers. Larger jades get pot bound in washtubs & have to be cut out to transplant.

I make a soil that seems to be liked by all of my cacti and succulents. It is two parts pine bark fines (soil conditioner/landscapers mix), two parts high fired clay (I use OilDri from Sam's Club marketed for cleaning up oil spills in automotive shops and for ammending soils), one part C&S soil, and one part tiny pea gravel. Many are against the soil conditioner/landscapers mix because it does break down over time, but I think the break down is slower in C&S because they aren't watered as often as other container plants. I use the same stuff in my mix for veggies but different ratios. For veggies, I have to change the soil every year or two, but those get watered everyday. You could replace the soil conditioner and the C&S mix with coir. I just bought two blocks of this stuff called Bed a Beast from Petsmart. It is coir (coconut husk). It is $5 a block and each blocks make 7-8 gallons of soil. It was suggested to me last year because it doesn't become as hydrophobic as peat based soils do between waterings. I am also not a fan of the perlite because it floats to the top. I use it in my veggies and ornamentals. I have a container right now that is nothing but white perlite on top with almost none mixed in the soil. I am going to make some soil with it and go ahead and repot. It is also my understanding that it doesn't break down nearly as quick. I think I am going to try two parts coir, two parts high fired clay, and one part small pea gravel and see what happens. A lot of times, I mix my soil and put it in a pot without a plant. I water it and make sure that it is draining properly. I also see how many days it takes to dry up, assuming that that time might be decreased with a plant in it actually using the water! ;0) Just be careful using too much peat based soil of any kind. It became so hydrophobic last year for me that if I let it dry out between waterings, I couldn't water from the top. You will most certainly have to water from the top because it is not feasable to pick up a 25 gallon container with a 50 lb five foot jade in it so that you could bottom water. You also don't want it in a saucer because if you get extra rain, you don't want it sitting in water. I would put it up on those little feet if you can. It helps keep the bugs from crawling into the hole. I use window screen on the bottom to make sure that minimal soil washes out the drain hole. If it is a huge pot with only one huge hole in the center, you might consider drilling some more holes around the main hole towards the outside of the ring. All of this, of course, is only what works for me.