To effectively answer this question, we need details on what happens to those credit card interest rates when they rise. Let's assume for now that they all rise to 17%, which is slightly below the national average. Let's also assume you don't pay retroactive interest - that would make paying those debts even more important FWIW.
Those assumptions mean that come March, you can save $3000 x (0.17-0.034)/12 = $34 a month in interest by paying off the $3000 credit card rather than putting $3000 towards your truck loan. Note how I computed that by finding the difference between your two interest rates on the credit card and the car loan. So, unless you can come up with an additional $3000 to pay that March credit card before the APR jumps, best to put $3k towards it now.
Meanwhile, what to do with the remaining $4k in cash you have left over? That entirely depends on how much money you can save before your next credit card APR jumps up. If you use it to pay down your truck loan today, you'll save about ($4000 x .034) x 9/12 = $102 on interest before November (9 months away). BUT come November, if you haven't been able to save more money to pay off that $3800 credit card, you'll start paying ($3800 x .17)/12 = $53.83 per month for that credit card interest. So within two interest payments, you'll have lost all the $102 savings against your truck loan.
These numbers aren't accurate to the decimal place, since the interest payments decrease as you pay off the principal, but they're pretty close. Moral of the story, high interest debt = very very bad. Pay it off ASAP. The credit card debt will be even more of a drag if you have to pay retroactive interest. Potentially MUCH worse.
EDIT: You say "I would really love to get rid of my truck payment", but I would look at it differently, since you're only paying 3.4% interest (relatively low). I would say: "Gee, I'd really love to get rid of my high interest debt and then work on my truck loan!". It's certainly your prerogative to play the balance transfer game, but as my numbers above show, it only takes a slight miss and 1-2 credit card interest payments for that to be a losing strategy. Remember, once you've paid off your high-interest debt, you can then work on your car loan free of worry about any high interest debt, and you won't have paid too much interest in the meantime.