Tried the Jump start packs a few years ago and found I needed it so infrequently, it was generally flat when I needed it..Now, it wasn't completely flat, but it had lost enough charge not to be able to start a 2.8L diesel..

If I was going to rely on one of these for real emergencies, I think I would have it rigged to trickle charge in the vehicle...I am not sure how exactly how to do this , as you probably don't want to over charge it either but it must be possible...

The other thing with these packs is once connected to the dead battery, don't crank it up straight away..Let it trickle a charge across for several minutes at least and then try starting the engine..This dramatically reduces the peak load on the pack...

Edited to add, if there is room on the vehicle, I think an additional battery with a proper split charging/isolator unit might be a better way to go and be more versatile as well...

Last edited by Pete E; 03/28/16.

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