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Hi Guys,
Just a heads up for you. I've been telling guys I build boxes for to buy the GM rags now before they stop selling them so they can get a good one compared to the aftermarket or those "rebuild" kits.
I sold the last 69-82 Rag I had last week so I went to my local Chevy dealer to get another one, he was out and ordered one for me. It's not the same and I'll be returning it and not recommending or supplying rags anymore.
Here is the link to NCRS I posted the other day. If you find one buy it. Once some figure it out they'll be buying them out and marking them up like the 63-66 were. I haven't seen all the variations of the aftermarket rags but the ones I've seen were pretty poor.

http://www.ncrs.org/forums/showthread.php?t=85456&uid=5501
 

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Gary,

What are your thoughts on the U-joint being installed instead of the rag joint?

I know of several that have made the swap to the U-joint and haven't had any serious problems within the last few years.

Do you think, if done right, the U-joint could be a good replacement when a quality rag joint can't be bought?
 

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Discussion Starter #3
I never used a U-joint in that application so I can't say. My preference would be to use the red GM rag. The current one may still function ok but it's not as good as the originals.
 

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IMO you can't beat a universal joint style over a rag joint if the question involves road feedback or durability. We've been doing this to lifted trucks for years as lifts tend to push the limits of stock steering parts. Lots of places offer intermediate shafts with the modification performed.

Mid 90s jeep grand cherokee is a good place to start looking for junkyard universal joints the same size as 70s/80s GM passenger car.

I personally wonder about some modern miracle fabric, kevlar weave in polyeurethane, that kind of thing.

Have met more than one old time wheeler that swore you didn't buy parts store rag joints, you cut them out of old tires as even a junk tire was better structurally than what rag joints are. Never done it, but is an interesting angle.
 

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The only reason i posed the question is because I seem to remember some arguments by some who believed that GM designed the system around the rag joint because it 'gave' a little and having a solid joint in place of it would put excess stress on the column and steering parts and cause a failure.

Like I said, I know of several individuals...not me yet, that have used a U-joint and not experienced any kind of failure.
 

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If you start looking at late models that use U joints from the factory (whatever factory it may be) the construction is actually quite a bit lighter than a C3 steering column.

Can Gary or anyone elaborate on what makes the GM red disc different than others? Is it durometer of the rubber or increased plys or ??

Good conversation about a WAY overlooked item.

Does anybody offer a "performance" rag joint??
 

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There were only two basic types of flexible coupling discs that were used in GM vehicles through the years. There was a 4 ply coupling disc (4 laminations of neoprene rubber and cotton cloth) and 7 ply coupling discs (7 laminations - neoprene and cotton.) Both discs were 3.4 inch diameter and 0.38 thick. Since both discs were the same thickness, the 7 ply disc was much stiffer than the 4 ply disc, (much less rubber in the same space with the 7 ply part.)

Also, since all of the discs were 3.40 diameter and 0.38 thick, the supplier came up with color coding paint to quickly identify one disc from another. The red paint signified a 7 ply disc with a screen ground face. I do not recall all of the other colors (green, orange, yellow) as to what went where.

The 7 ply disc provided much better road feedback because of the stiffness. The 4 ply disc was used with nearly all power steering vehicles because it provided much better hydraulic noise isolation with the increased thickness of rubber.

Corvette flexible couplings always used 7 ply coupling discs from 1963 through 1982. Power and manual steering Corvettes all used the same 7 ply disc.

Now Gary's excellent pictures of the most recent service flexible coupling for the Corvette shows a part with only a 4 ply disc. It also is a coupling and flange assembly that does not transmit electrical current from one side of the assembly to the other. All Corvette flexible coupling assemblies through the years either had a brass strap, a thin wire with crimped connectors, or a disc with a metal screen molded into the face. Whoever is manufacturing the current service coupling assemblies for GM obviously is not following the Saginaw product drawings.

As I mentioned to Gary I had heard a rumor that the supplier of the coupling disc was no longer able to purchase the fine wire mesh screen that has been molded into the disc since the early 1970s. I guess that the rumor was true. However, it would seem that Saginaw (or whoever is supplying the complete assembly) should again begin installing a brass strap or ground wire in the assembly. (They also should be able to observe and count the differences between 4 and 7 layers of cloth and rubber.)

I don't know if there may be a NHTSA issue with respect to not being able to blow your horn because the service coupling assembly does not transmit current.

Jim
 

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Jim, as usual, great info.

Thanks, :thumbsup:
 

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Here is the correct procedure for lodging a complaint with GM Service Part Operations (SPO).

"Per your Voice mail, I contacted a manager at GMSPO and explained the situation.

He informed me that the correct procedure is to go to a GM Dealer - Parts Department - and they will generate a Case#. This is then forwarded to the "Partech Group". Issues like this is what Partech specifically Manage."

So a flexible coupling that does not complete an electrical ground path for the horn ground circuit is not the same part that has been available through GM Service Parts for the last 40 years. If the screen ground coupling disc is no longer available, GM should go back to the grounding strap or the grounding wire as part of the flange and coupling assembly.

Jim
 

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The rag joint in my corvette has been replaced with one that has no ground path, and this is where I have been trying my best to find a good solution. I have not yet decided on a method to provide a ground path, but it will have to be done for my car to pass safety inspection. If anyone has a way around this without replacing it again I would greatly appreciate it, as the joint itself is in good shape.

~wd-40:buhbye:
 

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If anyone has a way around this without replacing it again I would greatly appreciate it, as the joint itself is in good shape.

~wd-40:buhbye:
I would think it should be pretty easy to make a "grounding strap" or jumper wire with a pair of crimp style eyelet or ring terminals, (with an ID large enough to fit the bolts in the rag joint), and a 3 to 4 inch piece of 14AWG stranded wire (teflon insulation would hold up well to the engine heat).

Looks like I might have to do this, since I rebuilt my column recently with an AutoZone Help! rebuild kit (didn't know there were these issues with aftermarket rags).
 

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I've had a U-joint in place of my rag-joint for 4 or 5 years now with no issue. Correct me if I'm wrong, but doesn't the rag joint allow of some misalignment of the steering box input and steering column shaft? The alignment of those two shafts is dependent on the position of the body on the frame, so the U-joint may not work for some.
 

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I've had a U-joint in place of my rag-joint for 4 or 5 years now with no issue. Correct me if I'm wrong, but doesn't the rag joint allow of some misalignment of the steering box input and steering column shaft? The alignment of those two shafts is dependent on the position of the body on the frame, so the U-joint may not work for some.

This might be a very wobbly subject. I too plan on installing a U-joint when my rag joint fails.

However, I have heard plenty of good and bad stories about them. The bad seems to be alignment, causing problems in the column. The good...a joint that isn't going to wear out and looks a lot nicer than a rag joint.

I think vibrations play into this, meaning your steering wheel would vibrate your hands a lot more with a U-joint.
 

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Jim Shea has posted numerous times that the u-joint isn't a good replacement for the rag joint in this design. I believe he stated that if the rag joint starts to fail you won't lose all steering as it has some safety built into it. Whereas a u-joint failure would be a total loss of steering...
 

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To the best of my knowledge (daily visiting several websites), I have not heard of anyone having a problem with their horn not working after replacing their flange and coupling assembly with one that does not have a grounding screen, strap, wire, etc.

However, there are probably many people that would not even think to check their horn operation after working on their steering system. (There are possibly other paths for the grounding current to pass through the steering column attachments back to the vehicle body.)

One other possible issue is that the most recent flange and coupling assemblies now come with a coupling disc with 4 laminations of cotton cloth and neoprene rubber. All Corvettes (from 1963 through 1982) have always come with coupling discs that had 7 laminations of cotton and rubber. The flange and coupling assembly with a 7 ply disc is much stiffer than the 4 ply part and would provide a more direct connection to the steering gear.

Jim
 

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I am interested in the u-joint replacement. I have an aftermarket rag joint t oreplace my original one, but would rather swap to a u-joint.

Can someone post a manufacturer or part number for the u-joint?
 

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Discussion Starter #19
The last new GM rag, red inked, I bought was after the appearance of the present purple ones and it cost me $140. I have it in my parts bin for my 72 or 75. They both have the red ones now. Unless someone is going to make them they way they were you're going to be stuck with the GM, aftermarket, or universals.
 

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Discussion Starter #20
Just an update. I haven't found any new rags I like. The closest one is still the GM one unless someone found something better. A quick look on ebay found the new imported ones with the wrong D flat and bolts, worn out originals, and other aftermarket brands that didn't look any better, usa made or not.
Not much a selection out there and doesn't appear to be getting better. Look for a grounded 7 ply rigid joint if you see one with the red ink and in a GM box buy it.
 
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