1964 c10 305 and 700r4 swap

[minitruckr28]

Hello guys,

i was just wondering if somebody can walk me threw a 3o5 with 700r4 swap. i know i have to cut out the cross member for the old three speed and use a 67 to 72 tranny cross member but i would like to know if my stock rear end needs to be changed. This will be my daily driver so i would like decent gas milage.

Thanks

[NEWFISHER]

3:73 to 4:10 rear gears are recommended by GM for use with 700r4 transmissions.

There are tons of threads on the swap. If you use the search feature in all sections, you will come up with a ton of great ideas that past forum members have posted for us to see.

[neal 66]

I used the original 3speed standard trans cross member for my 700r4,i removed all the rivets, removed the two angled support brackets on either side that go to upper frame flange,moved cross member back to were it was needed and drilled two holes for bolts on either side cant remember if there was much more to it than that but you get the idea. Hope this helps. worked for me.

[j_persinger66c10]

The swap is pretty easy, I'm doing a 305/T350 in mine. The crossmember will have to moved back and the emergency brake cable will have to be relocated. Also, you will have to shorten your driveshaft and upgrade your radiator to handle the V8. Then there is something with the 700r4 I was reading that you have to hook up correctly or you'll burn it up but I don't remember what that was.

[PGSigns]

If the 305 came with the 700 it should have the correct setup on it for the TV cable. Setting it up correctly is important. Then you need to figure out if the 700 is lockup or not. 99% chance it is a lockup and you will need to wire it up. I used the Ron Francis lockup controller on mine and it works fine.
Jimmy

[skysoldier173rd]

you will need to get rid of that old trans crossmember and either make or modify one for the truck. I fabricated one and it was quite simple as you can see. I used the factory rubber mount and it worked well. Since i didn't disturb the tv cable, it worked fine as it was. You will need however, to do a little wiring to adapt the 700r4, but it's not extensive. There are articles on this site that cover that. You can use the vacumn controlled electric switch or you can put in a manual toggle switch for locking the converter. This conversion is in my 60.

[kieth]

Originally Posted by minitruckr28

Hello guys,

i was just wondering if somebody can walk me threw a 3o5 with 700r4 swap. i know i have to cut out the cross member for the old three speed and use a 67 to 72 tranny cross member but i would like to know if my stock rear end needs to be changed. This will be my daily driver so i would like decent gas milage.

Thanks

If your truck came with a 6 cyl and a 3 on the tree It probably has 3:73 rear gears.

If it had a 4 speed most likely 4:10

Now the question becomes what is the diameter of the tires you run on the rear ? if they are stock size then you will be fine, but if you are going with 30" diameters on the rear you might be questionable on pulling them with a 305. send me the rear tire diameter from the ground to the top of the tire and I will plug them into a spreadsheet that figures speeds, and usable torque to the ground for different engine/ra ratios/ and transmissions. then we will have a little better idea how it is going to work. Kieth

send me a pm on this board along with your email address so I can forward a copy of the spreadsheet to you in a email.......