Just thought I'd share what I had to do in order to replace the worn out steering intermediate shaft on my '73 Caprice Classic. I could not find a direct replacement so I ended up having to contrive one from aftermarket bits and bobs.
As you can see the old one is atop and the new parts below. The telescoping shaft is a Borgeson and the mini Cardan joints are stainless steel bought off of E-Bay from varying manufacturers.
One of the immediate hurdles was finding a boot to cover the length of the sliding shaft. Unfortunately Borgeson supplies a ridiculously small boot incapable of protecting their own product. When I called Borgeson and inquired if they had a longer boot they told me I was the only one who ever brought that up.
Anyway you can see the problem, you can't allow dirt, water or any other foreign matter to enter the slider. Now on the GM intermediate shaft there are two areas that slide. One near the column that allows for installation/removal as well as normal body/frame flex and the other midway down that's nylon injected to hold till an accident and the steering column collapses. This is the safety feature that takes the brunt instead of breaking all your ribs in an accident.
I had to choose a length of slider that allowed for both instances since it would be foolish to delete an already engineered in safety device like that.
I found a place called Allstar that sells a replacement boot for one of their aftermarket shafts that was long enough to cover the slider.
Next I cut down the excess length off the Borgeson shaft and powder coated the exposed areas. This shaft is plain steel and will rust otherwise if not painted or coated.
I plugged the far end of the shaft to prevent water and other foreign matter to ingress upwards towards the slider.
The problem with the Allstar boot is the loose fitting on one end.
I made a simple adapter out of nylon 6/6 on the lathe and mill to take up the space.
It's starting to come together.
One of the joints came in natural stainless steel. I want all the components to be a satin black so I dismantled the joint, prepped and powder coated it.
I also removed the original trunnion cap seals and replaced them with better grade O-rings. I also removed all the cheap grease and greased them with a synthetic water proof infused Teflon grease. Will never have to worry about these again most likely.
I bought black oxide stainless screws to better match. That OCD kicking in again.
Did the same to the other already black joint and used Loctite.
I also bought black stainless screws to replace the large obtrusive generic fasteners and cut each one down so that when properly tightened only 1-2 threads would be above the joint for a low profile look installed.
Installed the boot, the stainless bands and it's ready for installation.
There is it compared to the original. It has all the critical functionality of the original and will last a long time.
On a side note I did have to enlarge the original flex coupler (aka rag joint) blue cover opening to allow the mini Cardan joint.
If you have a problem seeing the embedded pictures I might suggest another browser. I was told some have a problem viewing the pictures. I use Palemoon and have no problems viewing.