Difference between "D" and "3" on auto transmission?

D is drive where the transmission will shift through every gear automatically, 1, 2 and 3 are the gears, if you put it in one gear like 3, it will stay in that gear all the time and not shift automatically, for towing you would use 1 or 2, not 3.

d is automatic shifting

you start off in gear 1 you press the gas at around 3000 rpm it will shift for you then same thing in next gear

on 3 the transmission is locked in gear 3 so you accelerate in gear 3 this is good for low torque applications like ice or for stop and go driving

D is your 4th gear. Use 3 if you are towing uphill, or driving under conditions where extra traction is required. Normally, keep the gear shift in D. You will NOT wear out the transmission prematurely as someone wrote.

D allows the car to go into 4th gear or overdrive.If you are only doing city driving..45mph or under it is best to place the transmission in 3rd and drive. D or 4th gear only engages at 45mph or above and you can prematurely wear out 4th by driving in the city in D.

Drive will let it go into 4th gear(saving gas) for the highway and stuff like that. 3 just keeps it from shifting to 4th. it will shift from 1st to 2nd to 3rd and stay in third. thats how it happens in my truck anyway. everyone is writin that u start off in 3rd gear wich i really doubt.

D is overdrive (4th gear) 3 is just third gear. When you start off it's in 1st gear then it goes into 2nd and then into 3rd. Then it will go into 4th gear which is overdrive.

D- Is for drive,, 3 is for towing ,, Simple as that