If the engine->chassis ground has not been checked, and checked again, it is the natural thing to do first, as it's simple.

When you jumped it from the truck, how did you hook up the jumper cables in teh Volvo? Positive cable to battery+, and negative cable to ground on engine block? If so, you effectively bypassed the engine->chassis ground strap.

Put a known fully charged battery in the car, and use your jumper cables to make a temporary engine->chassis ground. That is to say, clamp one end of jumper cables to engine, somewhere on the intake manifold is good, as it's clean. Other end to chassis. I usually go with the studs that hold the strut mounts, as they are clean. Use *both* the the cables as ground straps, to maximize chances of having good connection.

Then try to start it, with it's own (fully charged) battery. If it starts, then replace or install a new ground strap.

That this happened after pulling the engine and transmission really leads me to think this is the most likely culprit. Maybe there was never an engine->ground, but for some other reason, it was getting good ground, but you disturbed that ground in the work you did...

In any event, you can perform this test about 3 times in times in time it took me to write this up.

Always simple first.


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-Matt I ♥ my ♂