If you are replacing the sinks, why wouldn't you want new GD's to go with it? They are pretty cheap in the grand scheme of things. I sure would.

Yes, you can reuse your current garbage disposal. We did. We thought it would be wasteful to simply get rid of it since it was working just fine. Besides, the money saved on that could go towards other things. Not everyone has money to just throw away.

I reused mine - it wasn't that old and I'm on a septic system so it hadn't been used all that much. It seemed perfectly good so I too couldn't see tossing it out just so everything would be brand new. Don't know where you get a new flange/gasket - plumbing supply I'd guess.

You can reuse it -- we did in our main sink because we'd already replaced that since we moved into this house and we only had one sink. We got a new Insinkerator Evolution for the prep sink and it is quieter. We didn't immediately replace the other one, but OI may get one when I'm stumped for something to give DH. ;) :D

ours was just a few years old. If yours is much older than that, I'd replace it. Otherwise -- go ahead and use the old one and replace it when you feel like it or it dies on you.

I reused mine - the only thing I did reuse - I had bought it just a year or so earlier - no reason to throw it out.

We reused ours for a year and just replaced it last month. But you can usually order a new flange from the company that makes your gd. Ours was a Kenmore so I went to the Kenmore site and found I could order just the flange and gasket. I think it cost me all of about $5. When we replaced the gd we replaced the flange again, too. This time we put in an ORB one (to match our faucet...sink is siligranit) that I ordered off e-bay.

Our plumber always tells people that if their disposer is "X years old", he wouldn't guarantee a leak free re-install. I can't recall how old he said, though. I'm thinking it was around 5 or 6 years. He said that the seals on them just don't install as nicely, the second time around. Food for thought.
Kompy

We had planned on getting a new disposer, because as someone else said "in the grand scheme of things" it's pretty inexpensive. However, when our plumber told us that our old one was in good shape, we reeled ourselves in and decided to use the old one. Why NOT use something that has worked well for us in the past, and the plumber confirms it's in good shape? We have not regretted our decision. BTW, we did get new flange thingie, the plumber got it. We didn't think about removing it from our old sink - when we sold it on Craig's List.

Kompy, maybe if I'd heard that before ---- I think mine was 4 years when we reinstalled it. No problems, just a bit louder, but I also wonder if the larger sink gives more for the sound to reverberate on. We don't' run it that often or that long, so until it dies, I guess we have enough around the rest of the house to worry about.

1) Buy a new flange -- they're cheap.
2) You can reuse -- the mount is standard, so when it dies it's very easy to replace. The only thing is you'll have to pay for new installation if you can't do it yourself that much sooner.
3) There is no excuse for having an old disposal installation not being leak free. Reusing the flange, perhaps because of the putty and such. But the disposal is just a glorified elbow--pipe in and pipe out--if the plumber can't make that leak free I'd worry he couldn't make the new one leak free either.

There are plenty of reasons that older model disposals can't be installed with any guarantee. Older models tend to have leaks because the chambers weren't stainless and rusted out. Or the plastic gets old and cracks from the vibrations or being banged about between the installs. I wouldn't install one that was out of warranty. Period. Most of the builder's grade models (crappy Badger models or GE models) really resent being reinstalled and the customer just ends up having to replace them 3-4 months later. If you can't DIY an install yourself, and your disposal is out of warranty, replace it.

This is one item that many people don't give much thought to, and they should. The new Evolution models out there are a HUGE improvement in quietness and capability.

Live, Great advice. That may be what he tells people..the warranty thing. And you're right, unless you're a DIY-er, the labor alone to replace the unit down the road would almost pay for an Evolution.

On a side note: I just replaced my disposer with an Evolution and it IS awesome! Very quiet...so quiet it kind of disturbs my DH.

And my co-worker saw a show on This Old House or one of those type shows where they went to the testing facility for this unit. He said they would put buckets full of chicken bones down it.

Blurb from thisholdhouse.com
Gnawing them bones
May 25, 2007
InsinkeratorÂs new Evolution garbage disposer accepts all kinds of castaway food waste into its gaping maw, yet uses noise-reducing technology to dampen sound by 60 percent. Its 40-ounce chamber grinds food in 3 stages, quietly pulverizing coffee grounds, corn cobs and the notoriously difficult celery stalk.

The $299 Insinkerator was one of the best kitchen products we saw at the International Builders' Show. I'll be wishing I had one this holiday weekend, because any serious griller has long since learned that rib bones are best gnawed over the sink anyway. Or, as my dad calls it, "counter eatin'."

Click on the link below to watch a youtube video below of a commercial showing how well it works.

And here's another commercial showing how quiet they are:
http://www.youtube.com/watch?v=uvB4KI1pF4M

Can you tell I love my Evolution???
-Kompy

Here is a link that might be useful: Insinkerator Evolution

Kompy and Live Wire -- glad to see you joining in oin this. We had an electrician at the house and were talking to him. We ran the Evolution for him adn he couldn't believe how quiet it was - like you could forget you had it one quiet. He had just installed a different one in a home the day before and was wishing he'd known about them then.

BTW, DH installed a new disposal in our last house -- no problem. When we moved into this house, I think the disposal went about a week later. DH went out and bought the 1HP model he wanted adn came home to install it. He couldn't do it because of the way the builder had installed and done the original piping. The plumber charged us $165 to install the new one. That would just about cover the 3/4 HP Evolution Compact and that model would handle all that most folks could throw at it.

FYI,
there is an in depth thread on disposals over at the Appliance Forum.

Here is a link that might be useful: Garbage Disposals at Appliance Forum

I'd replace it: garbage disposals aren't that expensive and the new ones are sooo much quieter. Kompy, I laughed because our new Evolution batch feed is so quiet that DH insists it can't possibly be working.

Go for it!