700R4 driveshaft solutions

[skymangs]

I have a 70 longbed fleet. Right now it has a th350 with a two piece shaft. I’d like to convert it to a 700R4. Does anyone know a shaft that would be compatible? Two piece, 1 piece... Any advice on the appreciated. I don’t want to have to cut and balance if I don’t have to.

[Bigdav160]

I've cut and re-welded more driveshafts than I care to count. I never had the need to balance.

YMMV

[Rick Bollinger]

I could be wrong but your driveshaft may bolt right up. The 350 and 700 share the same slip yoke and I believe may even be the same length. My 400 was 2 1/2" shorter than my 700 and a different yoke.

[HIGHWAY BY THE SEA]

When I converted my 68 longbed stepside to a 700R4 I had to have a special drive shaft made at a shop.

[kidatheart]

Originally Posted by HIGHWAY BY THE SEA

When I converted my 68 longbed stepside to a 700R4 I had to have a special drive shaft made at a shop.

Did your 68 have a TH350?

[HIGHWAY BY THE SEA]

Originally Posted by kidatheart

Did your 68 have a TH350?

No.

[skymangs]

Thanks all for the replies. I guess I was looking for a common solution. Like the driveshaft from a park avenue wagon is the perfect length, or something.

[Rick Bollinger]

67-70 trucks came with a 400 trans. I don't believe the th350 came till 71. I may be off on the years but I do know they came much later. Also when you go to set up your 700 consider using bowtie overdrive's TV kit for your carburetor. It's a little more expensive but cheaper than frying a new trans.

[tdangle]

The th350 and 200r4 are the same length The th400 and 700r4 are the same length. My 70 C20 came with a TH 350 trans

[skymangs]

Originally Posted by Rick Bollinger

67-70 trucks came with a 400 trans. I don't believe the th350 came till 71. I may be off on the years but I do know they came much later. Also when you go to set up your 700 consider using bowtie overdrive's TV kit for your carburetor. It's a little more expensive but cheaper than frying a new trans.

I bought a Loksr TV setup.

[skymangs]

Originally Posted by tdangle

The th350 and 200r4 are the same length The th400 and 700r4 are the same length. My 70 C20 came with a TH 350 trans

Maybe its a 400, IDK, I just assumed it was a 350. Have to look.

[Rick Bollinger]

I just swapped out my 400 for my new 700r4 and they definitely were not the same length. I cut my driveshaft down 2 3/4". My new yoke was a 1/4" longer than the old one. The 400 trans was 2 1/2" shorter than the 700 r4.
When you go to check your new trans be sure to check your pressures BEFORE you drive it. You can get the directions from the Bowtie overdrive website.

[Rick Bollinger]

Here is a link to there website. There is a lot of great info here.

http://www.tvmadeez.com/article/index.php

[Madkidd007]

This is actually quite simple. It depends on which th350 is in it, there is a long and short shaft. But at the end of the day it would have to be shorter if anything and not longer. Have it shortened & balances. Too cheap not to do it and guaranteed a smooth driveline

[Madkidd007]

Thought I’d add this also

[Warship2k15]

Originally Posted by Madkidd007

Thought I’d add this also

Good info.It looks like if you get lucky and have a long shaft turbo 350 that it will not need the driveshaft modified.

[Lancialonnie]

I just had the 350 in my 72 replaced with an early 700R4. The driveshaft needed to be shortened a little bit (either 1 1/2 or 2 1/2 inches, can't remember for sure). I dropped it off at the commercial shop that does lots work on large trucks and they had it ready to go the next day. It sure is nice having overdrive! I have to watch my speed on the freeway now as it is so quiet I don't realize how fast I am going!

[skymangs]

Thanks all. I Feel much more confident about this swap.