Problem installing c-beam
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Joined: Dec 2013
Posts: 59
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From: Grants Pass, OR
Problem installing c-beam
Still struggling with my 1985, one problem after another. Damn car-in-a-box.
I swapped out the D36 for a 1991 D44, that went off without a hitch. Swapped the driveshaft for the correct manual trans one. C-beam is another story.
Trying to install the beam the holes are off by about 3/8". I bolted up the rear and the mounting holes in the trans are 3/8" behind the c-beam holes.
I redrilled the trans end of the D36 c-beam, relocating the holes 24mm to the rear as was shown in a post. I just searched a while ago and found the measurement from the rear to front hole on the D44 beam should be 38 7/16" and the holes are dead on.
The engine and trans were out of the car when I bought it so no idea how well it lined up to begin with. The car is on jackstands and I can't figure out how the engine could be shifted back or the rearend could be shifted forward. I'm really at a loss here.
I swapped out the D36 for a 1991 D44, that went off without a hitch. Swapped the driveshaft for the correct manual trans one. C-beam is another story.
Trying to install the beam the holes are off by about 3/8". I bolted up the rear and the mounting holes in the trans are 3/8" behind the c-beam holes.
I redrilled the trans end of the D36 c-beam, relocating the holes 24mm to the rear as was shown in a post. I just searched a while ago and found the measurement from the rear to front hole on the D44 beam should be 38 7/16" and the holes are dead on.
The engine and trans were out of the car when I bought it so no idea how well it lined up to begin with. The car is on jackstands and I can't figure out how the engine could be shifted back or the rearend could be shifted forward. I'm really at a loss here.
Drifting
Joined: Aug 2010
Posts: 1,704
Likes: 8
Do you come from a Dana 36-automatic and do you want a Dana 44-manual swap?
Do you come from a Dana 36-automatic and do you want a Dana 44-automatic?
Since the Dana 44 is always coupled with a manual trans you have different lenght driveshaft and consequently a different C beam
I would put the engine and trans in again ,then i would put the rear diffrential and batwing assy.When i have this set up,then i can take measurement on Cbeam and figure out the whole challenge.
Do you come from a Dana 36-automatic and do you want a Dana 44-automatic?
Since the Dana 44 is always coupled with a manual trans you have different lenght driveshaft and consequently a different C beam
I would put the engine and trans in again ,then i would put the rear diffrential and batwing assy.When i have this set up,then i can take measurement on Cbeam and figure out the whole challenge.
Team Owner
Joined: Sep 2003
Posts: 25,394
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Never having done this and since the D44 C-beam is shorter than the D36 C-beam it would make sense that the "overall" length of the C-beam might need altered also.
You should have had to drill two new holes in the D36 C-beam and if they're appropriately placed you should have no issues unless the total length is the obstruction.
If you remove say 1/2" from the total length does that maybe complete the modification of the C-beam? Check also the "cut-out" on the transmission end of the C-beam. Just askin'
Make a template of the transmission mounting points both top and bottom and fit those to the C-beam and see what you've got!
You should have had to drill two new holes in the D36 C-beam and if they're appropriately placed you should have no issues unless the total length is the obstruction.
If you remove say 1/2" from the total length does that maybe complete the modification of the C-beam? Check also the "cut-out" on the transmission end of the C-beam. Just askin'
Make a template of the transmission mounting points both top and bottom and fit those to the C-beam and see what you've got!
Last edited by WVZR-1; Apr 5, 2014 at 10:16 AM.
Thread Starter
Advanced
Joined: Dec 2013
Posts: 59
Likes: 1
From: Grants Pass, OR
I've got an auto trans and a D44. The front and rear mounting points on both beams are the same. The difference is the length of the beam.
Here's the thread showing where to redrill.
http://forums.corvetteforum.com/c4-t...d-for-d44.html
Like I said, I found a thread with the center to center measurement on the D44 beam and the redrilled holes in mine are the correct distance apart.
I'm going to try it again today. The member that posted that thread suggested lifting the back of the trans further than I did so will see if that helps.
Here's the thread showing where to redrill.
http://forums.corvetteforum.com/c4-t...d-for-d44.html
Like I said, I found a thread with the center to center measurement on the D44 beam and the redrilled holes in mine are the correct distance apart.
I'm going to try it again today. The member that posted that thread suggested lifting the back of the trans further than I did so will see if that helps.
Team Owner
Joined: Sep 2003
Posts: 25,394
Likes: 2,741
I've got an auto trans and a D44. The front and rear mounting points on both beams are the same. The difference is the length of the beam.
Here's the thread showing where to redrill.
http://forums.corvetteforum.com/c4-t...d-for-d44.html
Like I said, I found a thread with the center to center measurement on the D44 beam and the redrilled holes in mine are the correct distance apart.
I'm going to try it again today. The member that posted that thread suggested lifting the back of the trans further than I did so will see if that helps.
Here's the thread showing where to redrill.
http://forums.corvetteforum.com/c4-t...d-for-d44.html
Like I said, I found a thread with the center to center measurement on the D44 beam and the redrilled holes in mine are the correct distance apart.
I'm going to try it again today. The member that posted that thread suggested lifting the back of the trans further than I did so will see if that helps.
Lifting isn't going to accommodate a 3/8" discrepancy.
Thread Starter
Advanced
Joined: Dec 2013
Posts: 59
Likes: 1
From: Grants Pass, OR
Got it resolved and it didn't have anything to do with the length of the beam. Like the instruction said, cutting isn't necessary, just a little grinding on the bottom of the transmission end to clear.
I think the problem is the nose of my rear diff is pointing up a bit, maybe due to the fact I tightened everything without the beam in there. I did load the suspension but must not have been enough.
I stuck a bolt through the back of the beam, slid the front onto the trans and slowly lowered it till the holes lined up.
I think I'll loosen up the rearend bolts, get the beam on, get the car on the ground and tighten everything up again.
Tough to diagnose problems by description alone but you got me looking in the right place. Thanks for the help.
I think the problem is the nose of my rear diff is pointing up a bit, maybe due to the fact I tightened everything without the beam in there. I did load the suspension but must not have been enough.
I stuck a bolt through the back of the beam, slid the front onto the trans and slowly lowered it till the holes lined up.
I think I'll loosen up the rearend bolts, get the beam on, get the car on the ground and tighten everything up again.
Tough to diagnose problems by description alone but you got me looking in the right place. Thanks for the help.
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Drifting
Joined: Aug 2010
Posts: 1,704
Likes: 8
Yeah,from the link you posted we can see you don't need cutting the Cbeam,but i'm not a great fun of all those holes so closed each other,i'm worry it may become weak.i'would have the holes soldered,grinded,and then drilled the new holes,just for peace of mind.
Team Owner
Joined: Sep 2003
Posts: 25,394
Likes: 2,741
Got it resolved and it didn't have anything to do with the length of the beam. Like the instruction said, cutting isn't necessary, just a little grinding on the bottom of the transmission end to clear.
I think the problem is the nose of my rear diff is pointing up a bit, maybe due to the fact I tightened everything without the beam in there. I did load the suspension but must not have been enough.
I stuck a bolt through the back of the beam, slid the front onto the trans and slowly lowered it till the holes lined up.
I think I'll loosen up the rearend bolts, get the beam on, get the car on the ground and tighten everything up again.
Tough to diagnose problems by description alone but you got me looking in the right place. Thanks for the help.
I think the problem is the nose of my rear diff is pointing up a bit, maybe due to the fact I tightened everything without the beam in there. I did load the suspension but must not have been enough.
I stuck a bolt through the back of the beam, slid the front onto the trans and slowly lowered it till the holes lined up.
I think I'll loosen up the rearend bolts, get the beam on, get the car on the ground and tighten everything up again.
Tough to diagnose problems by description alone but you got me looking in the right place. Thanks for the help.
Last edited by WVZR-1; Apr 6, 2014 at 08:55 AM.
Thread Starter
Advanced
Joined: Dec 2013
Posts: 59
Likes: 1
From: Grants Pass, OR
I give up. YEP, ya got me! I hacked about 3" off that sucker, slotted the holes 1/2" and ground the crap out of it just for good measure!
The beam is EXACTLY the same length as it was when it was originally removed from the car but thanks for the feedback.
The beam is EXACTLY the same length as it was when it was originally removed from the car but thanks for the feedback.
Team Owner
Joined: Sep 2003
Posts: 25,394
Likes: 2,741
You need to be shopping for the correct C-beam. You do NOT slot the mounting holes on either end.
