i have both now (GB70 & GBX75) . . . and looking at getting the GBX155 to upgrade my GB150.
the GBX USB fast charge is a nice addition.
the GBX 4cell vs 3cell as a good upgrade.
they added the 60sec timer.
but im sad they have ditched the 12v output from the GB range.
so my take is that they newer GBX range is a welcome improvement.
but id still say the GBX75 is the min size for a T6 and wouldn't bother with a GBX55 regardless of what the spec say.
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you need to remember that internal charge capacity is the important thing here, as soon as you connect the packs to the battery it will start loosing charge into the flat battery. ( which is a larger capacity than the jump pack . . . . so could swallow the whole pack dead - that's why they've added the 60sec timer)
then when you switch on the ignition you loose charge into the glow plugs and modules etc etc . . .
if you don't get the van started straight away you will dump the whole jump pack into the battery and van leaving you with nothing left for additional restart attempts.
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the GBX75 has almost twice the capacity of the GBX55 !!!!!!!
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GBX55: (46Wh capacity)
GBX75: (74Wh capacity)
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if you want one, get this one:
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