| i wouldn't worry about the speedo being off since according to my GPS it was off roughly 1MPH with the 265's versus stock tires..
no the 265's will not affect towing trailers with your Duramax.
__________________ James 
TyreBoyz Pulling Team
Pulling Truck called Late Nights
Puller/DD=04 LLY Reg Cab 2500HD,EFILive'd,Built Tranny and a fe fuel upgrades!
Business Truck
06 LBZ 2500 CC SB SRW,EFILive'd and a Built Tranny
DD/Beat Around
03 5.3L 1500 EC SB,Hypertech,Upgraded Tranny,Exhaust and CAI
Economy Saver
02 VW Jetta TDI,Stock for now but looking at a Chip,Nozzles and CAI!
tricycles = teaching childern from a early age that front wheel drive sucks  |