Good news on the diff. Pull the hubs and grease your axle bearings and make sure they are in good working order. The hubs need to be really tight when you put them back on. Oh yeah if the muffler has some small holes just plug them with JB Weld. You can buy a brand aftermarket new replacement slip-on for like $170.00 so good luck. Maybe you can weld and patch?
79 110
83 185S
84 250R
3x85 Big Reds
85 200X
85 ATC 70
85 Tri-Zinger
86 200x
86 TRX 125
87 TRX 250
89 TRX 300
98 TRX 450S
03 TRX 350
5 Foreman 500 4x4's
You can never have enough! ATC250ES is still the best!