Drive shaft too long after rebuild - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Berlinvet · 07-14-2018, 08:18 PM

Ok, perhaps you guys can straighten this out for me. I pulled the TH400 out of my 68 C10 Long Bed, changed the TC and put the tranny back in. So far so good. Now I cant get the darn driveshaft to fit. It's too long. The crossmember mates with the mount on the tranny and the original bolt holes, so I believe the tranny is in exactly the same position it was before - when I removed the drive shaft without any problems. It is all the way in the transmission, cant get it in any further. What the heck is this black magic?

bill3rail · 07-14-2018, 08:38 PM

Not sure about the 400's but some auto trannys have different tail shafts.
Did someone rebuild the tranny and put a different tail shaft on it?

Bill

Berlinvet · 07-14-2018, 08:41 PM

I can't tell. But that's not whats bothering me. I took the whole thing apart and now I cant put it back together. All same parts apart from TC and flex plate. What gives?

bill3rail · 07-14-2018, 09:24 PM

Quote:

Originally Posted by Berlinvet

I can't tell. But that's not whats bothering me. I took the whole thing apart and now I cant put it back together. All same parts apart from TC and flex plate. What gives?

When did you pull it?

When did you reinstall it?

Did someone rebuild it?

How far off is it?

Berlinvet · 07-14-2018, 10:09 PM

Pulled transmission 2 weeks ago, got new torque converter and flywheel, put everything back together today. No rebuild. Bell housing snug on engine, crossmember holes line up with frame and transmission mount. It appears the shaft won't slide any further into the transmission. It isn't binding, but ALL of the, excuse my laymen term, "shiny part" that goes on the splines is in there to the hilt.

Berlinvet · 07-14-2018, 10:10 PM

I'm missing a solid half inch in the rear and that would leave zero wiggle room for any forward or backward movement.

**dmjlambert** · 07-14-2018, 10:23 PM

Is that a 2-piece drive shaft with a skip yoke in the middle?

weq92f · 07-14-2018, 10:29 PM

Something is not right here... If the tranny is bolted snug to the block and the new TC didn't crunch in there somehow causing the shaft to not go deep enough, then the shaft should fit back where it came out!

Two piece shaft?

-klb

rjs53 · 07-14-2018, 10:42 PM

Did your torque convertor go all the way in? Your bell housing wouldn't fit flush with motor if it didn't Unless you really torque it down, in which you broke the pump. Check and see if the motor and trans are all the way together.

**Steeveedee** · 07-14-2018, 11:24 PM

Uh-oh, maybe you stacked the TC. If it isn't bolted to the flex plate yet, does it spin free?

**oldgold70c10** · 07-15-2018, 09:56 AM

Are you having trouble getting the drive shaft shifted foward enough to get the rear u-joint back where it goes? On my truck, the dive shaft will come off with no trouble, but to put back on, I have to jack the rear end up high enough that the shocks are fully extended. Only then will the rear u-joint go back in place.

Berlinvet · 07-15-2018, 10:11 AM

Thanks for all the replies. TC did spin before I bolted it to the flex plate. Bell housing mates to engine, no gap. They came together without me having to really torque down the bolts.

It is a 2 piece shaft with the skip yoke.

@Oldgold: yes, that is exactly my problem. REmoved the darn thing without a hitch. Ill try your technique of jacking up the rear.

**Steeveedee** · 07-15-2018, 10:34 AM

Quote:

Originally Posted by oldgold70c10

Are you having trouble getting the drive shaft shifted foward enough to get the rear u-joint back where it goes? On my truck, the dive shaft will come off with no trouble, but to put back on, I have to jack the rear end up high enough that the shocks are fully extended. Only then will the rear u-joint go back in place.

It it is done that way, the bolts attaching the center support to the frame must not be tightened until after the axle is raised back up to ride height, or the difference can push the bearing out of the support.

Berlinvet · 07-17-2018, 11:54 AM

Problem found but not solved. Yet. PO seemed to have forgotten to bolt engine down onto motor mounts. Engine shifted back about 2 inches when I pulled the transmission. Now I just need to pull her forward, somehow, and drive shaft should for again. Any pointers as to how that can be done?

cleszkie · 07-17-2018, 01:04 PM

You need to raise the engine/tranny combo with an engine hoist and shift everything forward. You should probably get new engine mounts while you are at it. This process might be easier if you unbolt the tranny from the engine first.

Its scary to think that the only thing keeping your engine from rolling around were your tranny mounts.

07-14-2018, 08:18 PM	#1
Berlinvet Registered User Join Date: Jul 2018 Location: SAN ANTONIO, TX Posts: 14	Drive shaft too long after rebuild Ok, perhaps you guys can straighten this out for me. I pulled the TH400 out of my 68 C10 Long Bed, changed the TC and put the tranny back in. So far so good. Now I cant get the darn driveshaft to fit. It's too long. The crossmember mates with the mount on the tranny and the original bolt holes, so I believe the tranny is in exactly the same position it was before - when I removed the drive shaft without any problems. It is all the way in the transmission, cant get it in any further. What the heck is this black magic? Last edited by LockDoc; 07-17-2018 at 05:15 PM.

07-14-2018, 08:38 PM	#2
bill3rail Registered User Join Date: Jul 2013 Location: LI, NY 11801 Posts: 1,140	Re: Drive too long after rebuild Not sure about the 400's but some auto trannys have different tail shafts. Did someone rebuild the tranny and put a different tail shaft on it? Bill __________________ 1970 C10 8' Fleetside, L6 250, 3 on the Tree. The most basic of pickup trucks!

07-14-2018, 08:41 PM	#3
Berlinvet Registered User Join Date: Jul 2018 Location: SAN ANTONIO, TX Posts: 14	Re: Drive too long after rebuild I can't tell. But that's not whats bothering me. I took the whole thing apart and now I cant put it back together. All same parts apart from TC and flex plate. What gives?

07-14-2018, 10:09 PM	#5
Berlinvet Registered User Join Date: Jul 2018 Location: SAN ANTONIO, TX Posts: 14	Re: Drive too long after rebuild Pulled transmission 2 weeks ago, got new torque converter and flywheel, put everything back together today. No rebuild. Bell housing snug on engine, crossmember holes line up with frame and transmission mount. It appears the shaft won't slide any further into the transmission. It isn't binding, but ALL of the, excuse my laymen term, "shiny part" that goes on the splines is in there to the hilt.

07-14-2018, 10:10 PM	#6
Berlinvet Registered User Join Date: Jul 2018 Location: SAN ANTONIO, TX Posts: 14	Re: Drive too long after rebuild I'm missing a solid half inch in the rear and that would leave zero wiggle room for any forward or backward movement.

07-14-2018, 10:23 PM	#7
dmjlambert Senior Member Join Date: Apr 2016 Location: Cypress, TX Posts: 3,561	Re: Drive too long after rebuild Is that a 2-piece drive shaft with a skip yoke in the middle?

07-14-2018, 10:29 PM	#8
weq92f Registered User Join Date: Oct 2016 Location: Dallas Texas Posts: 2,860	Re: Drive too long after rebuild Something is not right here... If the tranny is bolted snug to the block and the new TC didn't crunch in there somehow causing the shaft to not go deep enough, then the shaft should fit back where it came out! Two piece shaft? -klb __________________ 67 C10 fleet fuel injected '70 402, 700r4, 3.73 posi 07 335 sport turbo 6sp 94 Trans Am GT LT1 6sp posi -- sold after 22yrs 99 540 sport V8 6sp -- sold 73 240z L24 4sp -- given to friend 68 C10 step 350/350 3.73 open -- sold

07-14-2018, 10:42 PM	#9
rjs53 Registered User Join Date: Jan 2010 Location: nevada Posts: 649	Re: Drive too long after rebuild Did your torque convertor go all the way in? Your bell housing wouldn't fit flush with motor if it didn't Unless you really torque it down, in which you broke the pump. Check and see if the motor and trans are all the way together. __________________ 2003 Dodge 2500 1969 C10 2014 Camaro SS/RS/1LE

07-14-2018, 11:24 PM	#10
Steeveedee Who Changed This? Join Date: Jan 2013 Location: Simi Valley, CA Posts: 10,081	Re: Drive too long after rebuild Uh-oh, maybe you stacked the TC. If it isn't bolted to the flex plate yet, does it spin free? __________________ ~Steven '70 Chevy 3/4T Longhorn CST 402/400/3.56 Custom Camper Simi Valley, CA

07-15-2018, 09:56 AM	#11
oldgold70c10 Who's got steelies? Join Date: Feb 2006 Location: Morrison, Oklahoma Posts: 1,023	Re: Drive too long after rebuild Are you having trouble getting the drive shaft shifted foward enough to get the rear u-joint back where it goes? On my truck, the dive shaft will come off with no trouble, but to put back on, I have to jack the rear end up high enough that the shocks are fully extended. Only then will the rear u-joint go back in place. __________________ 1969 C10 LWB W/ 250 I6 & 3spd 1970 C10 with '67 small window cab, 68 front end, blue; 305/TH350, 3.08 limited slip rear end, manual brakes, power steering; & 4-wheel drums-My daily driver. 1975 Chevelle Malibu Classic Coupe 350/th350 mint green 1970 C20 Suburban 350/700R4 4.10 gearing green & white 1978 Big 10 Silverado 350/th350, working ac, 2 tone blue-My summer daily driver 1983 GMC 1500 Sierra 305/SM465 2.73 rear end How to add a trip odometer to your 67-72 stock speedometer How to rebuild your Q-Jet My Truck Page My Youtube Channel

07-15-2018, 10:11 AM	#12
Berlinvet Registered User Join Date: Jul 2018 Location: SAN ANTONIO, TX Posts: 14	Re: Drive too long after rebuild Thanks for all the replies. TC did spin before I bolted it to the flex plate. Bell housing mates to engine, no gap. They came together without me having to really torque down the bolts. It is a 2 piece shaft with the skip yoke. @Oldgold: yes, that is exactly my problem. REmoved the darn thing without a hitch. Ill try your technique of jacking up the rear.

07-17-2018, 11:54 AM	#14
Berlinvet Registered User Join Date: Jul 2018 Location: SAN ANTONIO, TX Posts: 14	Re: Drive too long after rebuild Problem found but not solved. Yet. PO seemed to have forgotten to bolt engine down onto motor mounts. Engine shifted back about 2 inches when I pulled the transmission. Now I just need to pull her forward, somehow, and drive shaft should for again. Any pointers as to how that can be done?

07-17-2018, 01:04 PM	#15
cleszkie Registered User Join Date: Feb 2003 Location: Santa Ana, CA Posts: 2,191	Re: Drive too long after rebuild You need to raise the engine/tranny combo with an engine hoist and shift everything forward. You should probably get new engine mounts while you are at it. This process might be easier if you unbolt the tranny from the engine first. Its scary to think that the only thing keeping your engine from rolling around were your tranny mounts.



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