This has been discussed some here and there, but there aren't any reasonably priced solutions to the stupidly designed LCA shafts used on many 3rd gen GM vans.
If you don't already know, Here's a quick overview. For some reason the LCA shafts on the vans have an inner shaft inside of the outer tube and the space between the shaft and outer tube is filled with rubber. (unlike the C-Pickups, which have solid shafts, but are a smaller overall diameter). See cut-away picture:
Rare Parts is the only place that I've been able to find new replacement shafts but they sell for over $300/ea. The Rare Parts shafts are nice because they are solid metal, but I can't bring myself to spend $600 on them. Every now and then NOS parts pop up on ebay for slightly less, but still hundreds of dollars, and still filled with rubber.
As seen in my build thread, I redid my whole front suspension recently and tried to replace every 30 year old wear part with new AC/Moog or some upgraded parts. The only parts that I re-used were the lower control arm shafts due to the stupid high costs to replace, and the impression that they didn't really go bad. Mine seemed to be in above-average shape so i chanced it.. This turned out to be a mistake. While the overall driving feel of my van was much improved, it has always had a tendency to wander a little. This is especially pronounced when under braking, crowned road surfaces, or pulling a trailer. And not the typical "old GM truck" type wander. It definitely felt like something was loose. I Inspected everything and even adjusted the new steering box which has no play. Still couldn't figure it out. Recently when I was messing with the carb, I ended up driving around with the doghouse cover removed. From the driver's seat, I was able to see the left LCA shaft. And what caught my eye is that when I hit the brakes, it moved... Significantly. The inner shaft was moving inside of the tube. I don't know if the rubber in mine is just shot or this is how they are supposed to be, but I was able to relate most of what I was feeling while driving to the movement of the LCA shaft.
Then yesterday, on Facebook I saw a post from a guy who managed to score (if you can even call it that) a pair of NOS Van LCA shafts for $100 each off of ebay. In the discussion it was mentioned that it was possible to source the solid, but smaller diameter, C10 LCA shafts, along with the C10 brackets and U-Bolts and then you can run the C10 shafts on the G-van.. He made it sound pretty simple, but didn't give much info besides that "LMC has everything needed". (It's the weekend now, but I plan to call LMC to verify this claim on Monday). If this is true, it may be a fairly simple and inexpensive solution to an issue that many here have run into. That being said, after spending more time searching/googling than I care to admit, I can not find anything else on the internet backing up this claim or verifying that it has been done successfully. The only picture I have is from the above-mentioned Facebook post showing the Van shafts next to the pickup shafts:Has anyone heard of this before??
If I can't find any other info before the van goes into hibernation for the winter, then over the winter, I'll pull the LCAs and do some measuring.
If the C10 shaft thing doesn't work out, I am still going to find a solution that doesn't cost several hundred dollars.
-Maybe I'll fill the voids in the shafts with JB weld..
-Maybe I'll see if someone can machine sleeves that can be pressed into the ends of the shafts to hold it solid where the rubber won't..
All I know is that OCD is a bitch and I'm going to come up with a reasonable solution. Hopefully it'll help others too.
I'll keep this thread updated.