I am stroking my 91 cherokee 4.0 with a 258 crank and 258 rods. My crankshaft end play is at 0.0055 inches. The range is 0.0015-0.0065 inches . The ideal range is ~ 0.002-0.0025 inches. My machinist tells me that the end play is perfect and less could cause friction problems, i.e burn out. To me, if it is engineered for .002-.0025 that should be the optimal range. I'm at the high end for wear according to the manual, and I see this giving me less engine life.
Also, my side cleance is 0.022 in. and .019 in. for two of the connecting rods. The range is 0.01-0.019 inches. My machinsts told me the .022 will not be a problem.
I'm concerned with my machine shops responce. Yes it will run fine, but how about 50K mi from now? Is my machinist BS'ing me becaused they screwed up or are the tolerances acceptable for a rebuild?