I purchased s/h a LT155 38" cut with c.150hours on the clock 4 years ago & it now has just over 1050hrs so it gets used quite a bit !!! (predominately on cutting 3cres of lawn & occasionally hauling a lightly loaded JD trailer with filled with mulch, or plants & garden tools) - after these hours no rust anywhere, engine has never been touched (apart from prescribed valve adjustment) & runs as new, the tuff torque tranny runs as new belts & spindles are original, in fact no component has needed to be replaced through wear - all in what can best be described as a harsh hot dusty & highly mineralised salty bush environment in undulating terrain.
Some people seem to hate the LT155, but I have nothing but praise for mine as it gets pushed well beyond its original design intent on the 3+ acred lawn on our farm & is used as can be seen by the hours frequently.
Only ever experienced 3 issues :-
1. Slight cracking on the bonnet (these composite/plastic bonnets seem too light to withstand the constant harmonic vibration
2. The wiring insulation started to break down from heat fatigue/age as it was routed too close to the engine & caused shorting on the block (easily fixed with spiral wrap & heat shrink insulation)
3. Installed a fuel line shut off tap to eliminate fuel build up when stationary & smoke at start up
As for maintenance, I wash/wax the LT155 once only max. once/year, blow the mower completely clean of debris with compressed air after every use, & do the following:-
1. Every 50hrs max. Change engine oil filter & replace oil with premium synthetic product
2. Every 10hrs max. Clean & reoil Air Filter, replace every 100hrs
3. Every 10hrs max lubricate spindles with high temperature bearing grease(rubbish in my humble opinion these spindles are fitted with grease fittings & supposedly only to be greased once at the factory for life) /lubricate steering with graphite moly farm grease
4. Every 100hrs flush transmission & replace oil with premium synthetic product (the tranny supposedly is sealed for life but the way I see it : oil breaks down, & hydrostatics hate heat & degraded oil so it's cheap insurance & relatively easy to do on this so called sealed unit)/adjust drive belt
5. Every 6 months drop the deck & paint with 2 coats of penetrol & then 2 coats of industrial gloss black paint to prevent rust/adjust deck belt