At first look, I think the AH-64 turbines are too long for fitting into the engine bay of any tank. Even the Turbomeca RTM332 of the WAH-64D (the British built version of the Apache), although a little more compact than the GE T700-701 series used in US built Apaches, is still too long to fit.
As for the M113, I am pretty sure that the engine and driveshaft components were specifically chosen from heavy truck manufacture. This allowed for quicker development time and more importantly, increased availability of parts worldwide for repair/replacement.
Originally the M113 used a (General Motors) Chrysler 75M petrol engine but from the M113A1 on, they switched to a (General Motors) Detroit Diesel 6V53 diesel engine.
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