700R4 Xmember Relocation Question

[Jahloha]

I removed my member because I have bought the POL xmember and tube engine mounts, but when removing my xmember, I saw the other holes people talk about.

So got me thinking, I have heard of people being able to relocate their existing xmember to accomodate the 700r4 being longer then the th350.

So for those of you who have done the 700r4 swap or have the knowledge help me distinguish how many holes, if any, I would have to drill in order to have the 700r4 fit correctly.

Thanks!

Here it is aligned in stock holes


Stock holes, another angle


If I slide the xmember down to where all holes align, here it is


Another angle

[Jahloha]

you can see that by shifting it down to where all holes line up, it shifts it roughly 3.5"

[snipescastle2]

The 700R4 (except the Corvette version) is 30 3/4" overall. The TH350 is 27 11/16" with the 6" tailshaft. TH350's also came with 9" & 12" tailshafts.
do you have a two-piece drive shaft or a one-piece? that will make a difference if you have to cut the driveshaft also. I'm pretty sure you would only have to drill two additional holes, or make a tab bracket to extend the mount attachment point to the cross member.
HTH,
Ben

[Katrina/10]

None of the factory holes lined up on mine, although it was close. I removed the brackets that bolt to the top of the frame, and drilled 4 holes in the bottom frame rail, I think it was about 2 inches back. If you can bolt up the trans, that is best way to make sure.

[Jahloha]

Originally Posted by snipescastle2

The 700R4 (except the Corvette version) is 30 3/4" overall. The TH350 is 27 11/16" with the 6" tailshaft. TH350's also came with 9" & 12" tailshafts.
do you have a two-piece drive shaft or a one-piece? that will make a difference if you have to cut the driveshaft also. I'm pretty sure you would only have to drill two additional holes, or make a tab bracket to extend the mount attachment point to the cross member.
HTH,
Ben

Originally Posted by Katrina/10

None of the factory holes lined up on mine, although it was close. I removed the brackets that bolt to the top of the frame, and drilled 4 holes in the bottom frame rail, I think it was about 2 inches back. If you can bolt up the trans, that is best way to make sure.

I just finished reading up on the stock xmember being unable to drop the pan unless you notch it. true? not true?

[Katrina/10]

That is true. The factory crossmember covers the rear pan bolt holes completely. I went ahead and used it as is, but it looks like trimming the front edge of the crossmember would allow access to the bolts.

[Z10]

I just made this swap this spring on my 72 GMC. I used the factory trans support and existing holes in the frame.

[Katrina/10]

I suppose it depends on what the truck originally came with. I changed from 6 cyl/powerglide to 350/700 and no trans crossmember holes lined up. Motor mounts in the forward frame holes.