I would just buy a set of Gators for your 48" deck. Here is a thread that might help.

Here is a link that might be useful: Pirahna Thread

Well, I have a Piranha deck and absolutely love it. I pretty much emptied my brain on the subject in the Piranha thread linked above.

I can't imagine any other mulching deck performing as well as a Piranha. The biggest thing to consider by far is the cost. You'll probably spend $900 for a new Piranha, vice $150 or so for a mulch conversion kit. Although you could probably sell your 48C for $400-500 if it's in good shape.

No problems with reliability so far. The loss of 2" per side might add to your open-field mowing time, but your trimming time will be reduced with the ability to cut against obstacles with either side of the deck.

Thanks for the feed back.

I really would like to hear from someone who uses the JD Mulch Kit for their 48" deck. I want to primarily mulch! My issue with buying the 44" Piranah dedicated mulcher is if I can not get to the lawn timely, the Piranah is said not to cut more than 1/3 of the length.

Marine Guy,
I hear the Piranah has a rear discharge baffle, if opened. Are you able to discharge clippings as you would with a side discharge deck? I wonder if the Piranah could cut more than 1/3 length if discharging out the rear of the deck?

Thanks.

I have a JD GT275 with a 48" deck, I do have a mulch plug for it, but have not used it for several years. The 17hp seems to limited in HP for it, grass needs to be very dry and ground speed has to be very slow with the mulch baffles installed. With some of the newer designed mulch blades it may be better, but it takes time to find the right combination and I don't have the desire to mulch that bad, will just side discharge.

I've never run the Piranha with the deflector removed. Not sure how that would work out. I currently have the mulch deflector installed (M120965) which, unlike a "mulch plug" does actually allow a slight discharge of clippings. There is also a rear discharge insert (M120966) available which you'd swap out with the mulching discharge chute, if you want to use it as a conventional mower. I'd guess it increases the airflow volume by about 3x, and I'm sure it would still mulch quite a bit, with six blades spinning over a 44" swath. If you read the US patent description, the original intent was that a homeowner could easily convert this deck into a neglected-grass mower for certain situations like returning from vacation. Go to the JD parts catalog (link below), click on equipment search, type "deck" then scroll down to "mower decks for LX, GT, etc... Click on Sectional Index, then "44 inch mulching mower." When you open up the "mower deck, chute and gage wheels" view you'll see what I'm talking about.

The Piranha will cut high grass. You just might have to go over it twice to mulch it completely. But it's not like your mower will become ineffective if your grass reaches 3". I previously owned a Cub Cadet with a mulch plug in the convertable deck. If the grass was too high it would basically clog up and leave about a third of the pass uncut. The Piranha doesn't do that, as far as I've seen. It just leaves clumps of clippings atop the otherwise evenly cut grass--if I let it get too long. Second pass elminates it completely. As long as I cut once a week, that doesn't happen.

I sit and think of all the time I wasted bagging and dumping grass clippings (and unclogging the chute). Now here I am, with the same end result (minus the 4x8' compost bin), and the organic matter is instantaneously recycled into the soil. What a great purchase; probably would have been worth paying retail if I hadn't come across such a good deal.
Nah, I'm too cheap to drop $900 on a mower deck. That extra $600 on top of what I spent buys a lot of Yuengling Lager and strip steak 5-packs from Sam's Club. I'd probably have to switch to Milwakee's Best and eye round steaks this summer if I'd paid full retail.

Here is a link that might be useful: jd parts catalog