This Dodge caravan has on year with a new gearbox. no problems found. The engine had a good service the past month (even rings, and valves....).
2 times I've experienced this issue: going arround 40 mph, I start the little ascent hill (going up to slope) and pushing the gas more to get more power and make the gearbox changes to gain speed in the road to up (going up to slope) , the "gearbox" or "engine" freezes, I notice the engine tries to demand the change to the gearbox but only a little loud is obtained, and the speed is the same (or less because going to up). it happens in 35-40 mph.

this road in Up is small is not complicated , it is a pit. , twice in the same road the same issue, demanding with the gas more push to get the gearbox change is not obtained and only a little loud is heard !
it happens only in the same road, the little "pit" I mean (because the little hill is a pit.

In other roads even more complicated to going up or more long , no problems found and the changes are good made, even with theA/C switched on! even in prolonged ways to up .

do you think this is a serious gearbox problem? I'm afraid!

currently Downshifts and upshifts are so smooth, quiet and good

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it is expensive repair the "speed control" ?? the automatic speed controller ?
can this electronic part make an interference with the gearbox - in some way causing the problem I mean ??


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we've noticed an air- scape, leak , in the red area marked there. the union must be relpaced. ! - an uncompression could affect the demand of power and changes in gearbox . (it is supoosed- we will check more and update ) :