I have a 91ish L3450 tractor, Recently using my backhoe, with the engine idled up, I could hear something sounding a little marbley. I idled it down and moved the tractor and it stalled. First time it ever did that. Drove it to my garage and it was bucking a little bit while driving. I pulled the hydraulic filter off and found a couple of small pieces of aluminum, like if you drilled something. Only a couple though. I cleaned out the filter screen and got quite a bit of fine aluminum particles out of it. There were some steel filings on the magnet in the filter too. Drained hydraulic oil out and it resembled a metallic paint mixture if you swirled it around. Tractor has about 1277 hours on it if gauge is correct. Not a lot of driving with it. Mostly idled up time to use backhoe. I don't know if this could be a clutch issue or a bigger problem with transmission. Any ideas?