do I have a 4:10?

They guy i bought my car from said he put a 4:10 in it(A4) but hasnt gotten it tuned yet.
when i drive my RPM'S are normal, but then when i put it in (1) the rpms dont slow down with the car, they just fall to 0 then when i hit the gass they rev up to where they would be cause im in 1 and then catch. why does it do this?

thats cuz of your trans, not your rear end...

your rear end wouldnt change when the engine would engage with the wheels.. the only way to know for sure is to open up the differential case, i think...

or ask someone with a A4/4.10 and ask what rpm/speed/gear they run..and compare it to yours! :)

easiest way ive found is to jack up the rear of your car and count how many times the drive shaft turns to one time of your wheel turning. for example on mine the drive shaft turned almost 3 times to the 1 full turn of the wheel, and knowing that stock they put 2.73 gears in the 79s my guess is that its those. for yours it should turn a full 4 times to one turn of your wheel if you have 4.10 gears

easiest way ive found is to jack up the rear of your car and count how many times the drive shaft turns to one time of your wheel turning. for example on mine the drive shaft turned almost 3 times to the 1 full turn of the wheel, and knowing that stock they put 2.73 gears in the 79s my guess is that its those. for yours it should turn a full 4 times to one turn of your wheel if you have 4.10 gears

That's actually a clever idea. I never thought of that.

yeah.. o.o maybe i should do that on my car..