700r4 driveshaft length - The 1947 - Present Chevrolet & GMC Truck Message Board Network

skokie · 03-17-2005, 12:31 PM

Can someone tell me the driveshaft length if you are conveting from a 400 turbo to a 700r4 on a 68 1/2 ton swb?

Thanks

chickenwing · 03-17-2005, 02:34 PM

Ya might want to call up your drive shaft shop and ask em how they want you to measure it. I've got a 2 piece shaft and they wanted from the rear seal to the center of the carrier bearing.

skokie · 03-17-2005, 02:47 PM

I was kinda hoping to run into someone up here who has already done it I have a one piece driveshaft. About the only thing the previous owner did that was right

Tx Firefighter · 03-17-2005, 05:09 PM

I used a stock driveshaft out of an 83 short bed truck in mine when I swapped to 700R4. It was the right length and yoke already. It required an adapter rear u-joint, available at any parts store.

This was a short bed truck with V8 in proper V8 position and 700 trans.

**Downtown** · 03-17-2005, 08:06 PM

I used the drive shaft out of a 1986 caprice. Worked just fine.
Hope it helps.

chickenwing · 03-18-2005, 10:08 AM

Key in on what Tx said about "V8 in proper position"...

Tx, is the proper position the forward mount where there is plenty of room between the firewall and distributer or the rear mount where there is very little room between the distributer and firewall? I've saw both but do not know which one is correct. Mine is forward, and I like it that way for when you have to remove the dizzy.

Downtown, what truck model and engine/ engine location?

**pjmoreland** · 03-18-2005, 02:00 PM

I just dropped my drivesaft off at a driveline shop this morning on the way to work to have it shortened for a 700R4 I'm putting in my 72 SWB. I stuck the yoke out 3/4" and measured the length of the driveshaft at 56 1/4" measured at the centers of the u-joints. I had a TH350 transmission in my truck before. The driveshaft is being shortened by approximately 3 1/2". By the way, my 350ci engine is in the forward position, away from the firewall. Hope this helps.

Guff · 03-18-2005, 03:38 PM

TCI's website has some good info on transmission dimensions. I'm not sure if you can just take the difference in lengths between the 700R4 and the TH400 and remove that from your driveshaft though.

Anybody know how much it should cost to shorten a driveshaft?

**pjmoreland** · 03-18-2005, 04:05 PM

Got a call about an hour ago from the driveline shop saying that my driveshaft is done. It cost me $65 to have mine shortened.

**Downtown** · 03-18-2005, 06:55 PM

The truck is a 71 SWB with a 350/th400 in the forward mount position. Swapped out to a 700R4 with very few modifications. And if you get the tailshaft housing off a early 80s 700r4 you can mount on the cross member without blocking the pan. The early 700r4s had two mounting places. The later transmission have only one mount and the mount is towards the front and block the bolts on the trans pan.

**pjmoreland** · 03-18-2005, 08:34 PM

With that older style tail housing, you could put a deep pan on the transmission. Wish I'd known about that before I installed my 1988 700R4!

**pjmoreland** · 03-18-2005, 08:41 PM

The information on the TCI website looks about right. They say the length of a TH350 is 27.6875" and the length of a 700R4 is 30.75". The difference is 3.0625". I had my drive shaft shortened about 3.5", but with my TH350 there was only about .25" of the yoke exposed at the back of the transmission, and I wanted that increased to .75" as recommended by the local driveline shop. As long as you don't have a radical suspension lift, going by the lengths of the transmissions would work fine. It's always best to measure, just to be safe.

Tx Firefighter · 03-20-2005, 07:35 AM

When I say proper V8 position, I mean front holes, forward mounting.

The rear holes are inline 6 position on 2wd trucks.

chickenwing · 03-20-2005, 06:43 PM

Thanks Tx..

03-17-2005, 12:31 PM	#1
skokie Registered User Join Date: Oct 2003 Location: San Jose Ca. Posts: 3,334	700r4 driveshaft length Can someone tell me the driveshaft length if you are conveting from a 400 turbo to a 700r4 on a 68 1/2 ton swb? Thanks __________________ RIP to my son Dylan. 5/17/2002 - 8/18/2018 If you want to know more about rare forms of pediatric cancer or if you want to help fund pediatric cancer research, please check out the website for the non-profit I started. https://slothforpedcancer.org 68 build thread http://67-72chevytrucks.com/vboard/s...d.php?t=223234

03-17-2005, 02:34 PM	#2
chickenwing Lovin' Life in Miss.! Join Date: Mar 2004 Location: Puckett, Mississippi Posts: 1,937	Ya might want to call up your drive shaft shop and ask em how they want you to measure it. I've got a 2 piece shaft and they wanted from the rear seal to the center of the carrier bearing. __________________ The truck... you hear that? No really, you did hear that?!!!

03-17-2005, 02:47 PM	#3
skokie Registered User Join Date: Oct 2003 Location: San Jose Ca. Posts: 3,334	I was kinda hoping to run into someone up here who has already done it I have a one piece driveshaft. About the only thing the previous owner did that was right __________________ RIP to my son Dylan. 5/17/2002 - 8/18/2018 If you want to know more about rare forms of pediatric cancer or if you want to help fund pediatric cancer research, please check out the website for the non-profit I started. https://slothforpedcancer.org 68 build thread http://67-72chevytrucks.com/vboard/s...d.php?t=223234

03-17-2005, 05:09 PM	#4
Tx Firefighter Watch out for your cornhole ! Join Date: Jun 2003 Location: Azle, Texas Posts: 14,162	I used a stock driveshaft out of an 83 short bed truck in mine when I swapped to 700R4. It was the right length and yoke already. It required an adapter rear u-joint, available at any parts store. This was a short bed truck with V8 in proper V8 position and 700 trans. __________________ I'm on the Instagram- @Gearhead_Kevin

03-17-2005, 08:06 PM	#5
Downtown Senior Member Join Date: Dec 1999 Location: New Palestine, IN Posts: 470	I used the drive shaft out of a 1986 caprice. Worked just fine. Hope it helps. __________________ 72 Shortbed fleetside 402 BB, AC, Posi 72 Super Cheyenne Longbed 350 49,000 original miles and My dad ordered it new 66 Chevy Caprice 2 dr 77 Caprice Estate Wagon New Palestine, IN

03-18-2005, 10:08 AM	#6
chickenwing Lovin' Life in Miss.! Join Date: Mar 2004 Location: Puckett, Mississippi Posts: 1,937	Key in on what Tx said about "V8 in proper position"... Tx, is the proper position the forward mount where there is plenty of room between the firewall and distributer or the rear mount where there is very little room between the distributer and firewall? I've saw both but do not know which one is correct. Mine is forward, and I like it that way for when you have to remove the dizzy. Downtown, what truck model and engine/ engine location? __________________ The truck... you hear that? No really, you did hear that?!!!

03-18-2005, 02:00 PM	#7
pjmoreland Senior Member Join Date: Jan 2005 Location: CA Posts: 5,460	I just dropped my drivesaft off at a driveline shop this morning on the way to work to have it shortened for a 700R4 I'm putting in my 72 SWB. I stuck the yoke out 3/4" and measured the length of the driveshaft at 56 1/4" measured at the centers of the u-joints. I had a TH350 transmission in my truck before. The driveshaft is being shortened by approximately 3 1/2". By the way, my 350ci engine is in the forward position, away from the firewall. Hope this helps.

03-18-2005, 03:38 PM	#8
Guff Registered User Join Date: Feb 2002 Location: illinois Posts: 78	TCI's website has some good info on transmission dimensions. I'm not sure if you can just take the difference in lengths between the 700R4 and the TH400 and remove that from your driveshaft though. Anybody know how much it should cost to shorten a driveshaft? __________________ -Guff 1969 C10 LWB, 350, 700R4, 3.73 gears Last edited by Guff; 03-18-2005 at 03:49 PM.

03-18-2005, 04:05 PM	#9
pjmoreland Senior Member Join Date: Jan 2005 Location: CA Posts: 5,460	Got a call about an hour ago from the driveline shop saying that my driveshaft is done. It cost me $65 to have mine shortened.

03-18-2005, 06:55 PM	#10
Downtown Senior Member Join Date: Dec 1999 Location: New Palestine, IN Posts: 470	The truck is a 71 SWB with a 350/th400 in the forward mount position. Swapped out to a 700R4 with very few modifications. And if you get the tailshaft housing off a early 80s 700r4 you can mount on the cross member without blocking the pan. The early 700r4s had two mounting places. The later transmission have only one mount and the mount is towards the front and block the bolts on the trans pan. __________________ 72 Shortbed fleetside 402 BB, AC, Posi 72 Super Cheyenne Longbed 350 49,000 original miles and My dad ordered it new 66 Chevy Caprice 2 dr 77 Caprice Estate Wagon New Palestine, IN

03-18-2005, 08:34 PM	#11
pjmoreland Senior Member Join Date: Jan 2005 Location: CA Posts: 5,460	With that older style tail housing, you could put a deep pan on the transmission. Wish I'd known about that before I installed my 1988 700R4!

03-18-2005, 08:41 PM	#12
pjmoreland Senior Member Join Date: Jan 2005 Location: CA Posts: 5,460	The information on the TCI website looks about right. They say the length of a TH350 is 27.6875" and the length of a 700R4 is 30.75". The difference is 3.0625". I had my drive shaft shortened about 3.5", but with my TH350 there was only about .25" of the yoke exposed at the back of the transmission, and I wanted that increased to .75" as recommended by the local driveline shop. As long as you don't have a radical suspension lift, going by the lengths of the transmissions would work fine. It's always best to measure, just to be safe.

03-20-2005, 07:35 AM	#13
Tx Firefighter Watch out for your cornhole ! Join Date: Jun 2003 Location: Azle, Texas Posts: 14,162	When I say proper V8 position, I mean front holes, forward mounting. The rear holes are inline 6 position on 2wd trucks. __________________ I'm on the Instagram- @Gearhead_Kevin

03-20-2005, 06:43 PM	#14
chickenwing Lovin' Life in Miss.! Join Date: Mar 2004 Location: Puckett, Mississippi Posts: 1,937	Thanks Tx.. __________________ The truck... you hear that? No really, you did hear that?!!!



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.