- You said the problem with turning is the weight, if that the case, not much i can help, there are many heavy-type vehicle, but none of them are APC so it hard to find something that is heavy & have small turn radius. The only solution for this is to make the vehicle lighter, sure it wont be able to run over zombie that easy anymore, but at least it look good when turn i guess

- How ever, there a similar mod like your in Build 41, the mod name is "♥♥♥ - M113A2 Armored Personnel Carrier", their model maybe isnt my style to say the least, but their APC can turn some what smooth if you asking me, you can check it out & maybe learn few thing that can apply for this mod



- One thing im noticed about how your APC turn is "location of the wheel", i dont know how coding work & how you make track run, so i will keep it as simple as how i see it

+ First off, let assume this, the track is just animation & the APC using normal wheel to move & turn, it just invisible
+ Let say: W1 is front wheels, W2 is back wheels, ======> is the body of APC. From how it turn, i feel like this is how the APC wheels located:

====APC body====>
W2................................................W1

That why it turn like a bus, cause the front wheel feel like it put way ahead of its body. Dont make the wheel like this also, it can still make the APC feel drifting while moving

====APC body====>
W2.............................W1

Put the back wheel at the center & the front wheel a bit behind the front, it should be like THIS:

====APC body====>
...............W2...........W1

This, THIS would make the APC turn better or at least more natural cause "center of turning circle" is the back wheels, but since APC have track, the center point of the track is the center of turning circle

That all info & idea i can offer to help improving the mod, while it just my assumption but i hope it can help improve the mod