Your 2010 diesel has a glow plug system, if you use the plugs "use no ether". As to your track adjuster problem, next to grease zerk should be a plug remove it, if not remove zerk "I guess that's how you spell it" you may have to bump idler on something solid, grease should come out and remove tension. To fix the adjusting cylinder that leaks the only way I know is to drive out master pin on track and pull idler forward then remove cylinder and replace seals. Good luck with your project, lots of old John deere still working every day, but like anything made of metal with a motor something will break. I got nothing done today had to replace starter and hydraulic hose on my JD 440 wheel skidder, stuff happens. Take care Chris