I don't have near the experience or expertise as Ryan, but I would have said "shaft issue" also. 

My situation with the driver was just the opposite.  Last year I upgraded from an off brand driver to the 909D2 with the Diamana Blue shaft in a Reg flex.  I was all over the place: 33% left, 33% center, 33% right with few fairways hit.  

This spring I had a chance to buy a 909D3 head at a reasonable price and decided to shaft it with a UST Proforce V2 in a Reg flex (as I had hit that shaft before and liked it). I wanted a second/backup driver and the chance to find one that was working better than what I had.

The combination was pure gold for my swing.   Since I've started exclusively using the 909D3 with the UST shaft, over the last 45 holes of golf, statistically I have hit 75% of fairways with the driver, missing equally 12.5% to the right and 12.5% left.  My driving as never been so consistent and  "down the middle".   The last round I played was only 9 holes, but I hit 5 of 6 fairways and the only one missed I drove too long and through the fairway on a dogleg.   All drives dead center.

Get back to the shaft that works for you.

Shaft could be part of the problem.

According to this site, the 905t is a high launch and the 909D3 is a mid launch, they are made for different swing types.

If you set the 2 on a hard surface, like the kitchen floor, the t probably sits with the face more closed than the D3.

This would be like me switching from a 983K to a 907D2, the D1 sets up just like the 983K, the D2 does not. The D1 I can swing exactly like the 983K, the D2 swinging like the 983K I can hit straight but very low and less distance(983k is 8.5 and D2 is 9.5). If I move the ball forward and swing more up I can hit the D2 much better. If I try to hit the 983K like the D2 then I get lots of hooks and poor impact.

I wouldn't recommend changing your swing type to fit the club.

I'm using the D2 just like the 983k because of the wind, when the wind dies down I'll probably switch to the D1(even though it sounds awful).

I used to play the ball forward and swing well up on the ball, I got the 983K and started working my swing down to a sweep or slightly down on the ball, to me this works much better. I have hit the 909D3 and it is a club that works best swinging up.

I agree with the others "if it ain't broke don't fix it!"   I tried one of the new fangled drivers from another vendor a week ago (the ones with the multi adjustable shafts).  The session confirmed that what I had in my bag is what works for me.

Is youir current shaft shorter than your old?  A club too short or too flat of a lie angle will slice or fade. . 

no the shafts are exacty the same length. im thinking that maybe the weight difference could be a factor, being that the diamana is heavier and making me over swing a touch. i played today with the 905 and struck the ball beautifully off the tee, hit it far n the perfect launch angle. im going to do an experiment, purchase a new ys6+ shaft, tip it 1/2 inch like i have now and put it in the 909 and see what happens.

Where's the like button?  :)

hey ryan, not sure if you know the answer but figured couldnt hurt to ask. the ys6+ tipped 1/2 inch will play similar to what shaft not tipped? by stiffining the shaft that much it would be comparable to what?

It may be close to a Titleist  Kaili 65 X, but we are comparing apples to oranges.  It basically would play between a YS-6 Stiff and a YS-6 X. 

RC