krackenvette

At time 11 min in this video you can see the ring on driveshaft.
It pulled the rear seal out of the transmission partially, see pic, but the ring is off of yoke just flopping around. Is it needed? Service manual says nothing of it, its generic GM when it comes to propellor shafts apparently.
Here is a picture of mine. I will take it out over next weeks time..

WVZR-1

Until the drive-shaft is removed you can't confirm the condition of the slip-yoke OD sealing surface. If the surface is fine many would replace the rear seal, remove the dampner and reinstall. Not me.

If the OD sealing surface is good I'd consider maybe just u-joints and a balance of the drive-shaft. For the transmission a new extension bushing if it hasn't been done recently along with the extension seal.

An option would be this Spicer slip-yoke, 2-3-9211X which has the correct counter-bore for the application but no dampener. If you wanted this slip-yoke is similar 2-3-4911X but has no counter-bore but similar length. Depending on the build of the transmission the counter-bore isn't required. That get's debated from time to time.

Spicer 2-3-9211X preferred always if doing new!!!

Tom400CFI

I'm "that guy". I wouldn't replace the damper. I don't think it's there for mechanical reasons (as a crank damper is). I think it's there for NVH that most of us will never observe.

What torsional vibrations even exist at that point in the drive line, that need damping?? If your U joints are aligned right, ain't no vibes coming from the rear....and your tq Converter should dampen pulses from the engine. So....
Teach me something.

WVZR-1

Two of maybe the 4 - 5 I've done or seen done here had questionable sealing surface, the rest didn't. 2 were helping a fellow and the rest 'for-hire'. I wouldn't consider a 'for hire' without the balance, I doubt you would either knowing what's involved doing it again!!

I didn't even hint the dampner was needed! The slip-yoke with dampner I don't believe was ever offered by Spicer, that was for the OE/GM only.

I've had a Spicer bulletin for years regarding the C4 early drive-shaft components. The bulletin done in '86 I believe has errors OR the slip-yoke I mention was released later less the dampner

krackenvette

I will pull driveshaft out tomorrow, hopefully. So, that ring is not necessary. I will take the driveshaft to Jamisons Corvettes and talk to kerry. Is it a non balanced ring?

383vett

After I converted a Dana 36 to 44, the driveshaft I used had a ring. I pressed it off and had no problems. People switch to aluminum and carbon fiber driveshafts to cut down on rotating weight. Didn't make sense to keep it on.

krackenvette

The transmission has less than 4kmiles on it, not hard miles either.
The U Joints were replaced in 2012 with Spicers, but there has been very little miles put on it since I came back from Hawaii, maybe 2 kmiles. Maybe.

krackenvette

This is same thing I did when I went 36 to 44. This driveshaft came from Ikerds.
Seems to me it is just added weight.

krackenvette

When I did the u joints, they fit real tight, there was no room for movement with the snap rings.
I did not know there was anything else to be done, as far as aligning them? educate me please.

Tom400CFI

There isn't, really. U-joint alignment is something that is basically set at the factory, and shouldn't change unless the car has been bent (accident) or some mechanic really f'd it up putting something back together.

Basically, what ever the angle of one u-joint is, the other joint has to have the same angle. The u-joint changes the rotational velocity of the shaft, becoming more pronounced as the angle of the joint increases. See in this revealing video...



The U-joints come from the factory properly "clocked" and with proper, equal angles at each end. So, my original point was that as long as that geometry hasn't been royally f'd up....I can't see how the front yoke of the driveshaft could have any meaningful torsional vibrations that would need the help of a damper.

WVZR-1

Ikerds supplied the D44 shaft assembled with that slip-yoke or you put your original slip-yoke on the D44 shaft sent from Ikerds? Depending on how you respond to this might influence a reasonable decision. Miles since u-joints done in '12?

So long as the OD sealing service of the slip-yoke is fine you should be able to just remove drive shaft, remove the ring, do the extension seal, put it together and drive on. I have one here I believe so I'll look.

***I looked and my damper has 4 'balancing bores' in the outer ring. Just curious > yours has how many?

Perhaps the 'shop' has an opinion regarding balance.

This is a 'new' before the dampener was pressed on. Most likely just toss the ring, peel the bonding material and leave the inner ring that's pressed on. It should become obvious when removed.

krackenvette

Once I get it out today, i will post pics etc.
I rarely drove the car when in Hawaii. In 12 years, 28000 miles. The Differential was done years ago, just cant remember right now, 2004 era.. The driveline, Ujoints etc was done in 2011 2012 timeframe. Then when I came here, rarely drive it, just to keep things lubed and stuff, maybe 100 miles a day, twice a year.
I honestly dont remember if Ikerds sent me the whole driveshaft ready to go, or I swapped the yoke..

WVZR-1

This might be a better read for you.

http://cf.linnbenton.edu/eit/auto/kr...riveshafts.pdf

Phasing/clocking or whatever shouldn't apply to the OP's issue!

Phasing(poor word choice) on a one piece shaft is done when the end-yokes are correctly orientated when welded in the tube. A builder here that I used often 'scribes' both ends of the tube at the end-yoke and also center of tube. If you've a substantial bit of power you can always just eye-ball the drive shaft, use a string or straight edge to check for twist. A couple friends actually ink/paint an edge on their drive-shaft to check.

If you asked him to fabricate a drive shaft using less than his 'suggested' tubing size (diameter & wall thickness) and you returned complaining he used the 'twist' to explain why you should have done it his way!

If you have a large fleet with longer wheel bases you should be familiar with 2 or 3 piece drive shafts. You need to pay particular attention at every coupling at every support to assure it's correctly 'phased'. Mark them all when you separate.

I'd think many here are should be familiar.

Tom400CFI

Yeah, I know. Neither should angle. Phasing is the shaft builder's responsibility, angle is the OEM's.

I was simply covering my bases (all possible scenarios), when I said:
"If your U joints are aligned right, ain't no vibes coming from the rear"

Then the OP asked for more detail about drive line angles, so I posted the simple, easy to understand video.

krackenvette

Okay, Got driveshaft out. Yoke ring just fell out. I guess its a damper like crank damper with rubber in it? Well, it was completely gone. No holes to assume a balancing on ring. The driveshaft does have a weight on it, as it was balanced.
Yoke has wear, but no grooves in it. I cant get a razor to catch on anything..
But, here is pictures. I am going to eat lunch. I will try to contact jamisons in regards to a shop that balances drive shafts. I am usually pretty impatient, but I will get it balance checked..

Thoughts?

Tom400CFI

Yes, the damper is a torsional damper, like a crank damper. My beef with it is; I can't see how/what torsional vibrations would exist at that point in the drivetrain. I look at that thing and think; "**** ya don't need on a huntin' rig!"

If you can't get a razor to catch, and it wasn't leaking oil out the tail shaft seal (before the seal was dislodged), then I'd bang a new bushing and seal in there, and throw it back together w/o the damper ring on it.

Was it vibrating before the ring came dislodged? If not, I wouldn't bother with balancing. If it was, then I would.

383vett

I would lube on the end of the shaft and install it. You didn't have a leak before and you shouldn't now. If you have a vibration, get it balanced. Actually, if the driveshaft shop is nearby, have them check the balance now. You won't have to drop the exhaust twice and it shouldn't cost much.

krackenvette

Need to find a shop first, that does balancing. There was no vibration before.
Weird how this thing just disintegrated the rubber..

Tom400CFI

Eh....rubber probably got hard from age, exhaust heat etc....then the damper ring trying to dampen whatever, broke up the hard rubber.

krackenvette

Got driveshaft back today, 40 bucks. Did not need balance weights according to company I took it to..
Put it in today, and report back.... HooYah.