Mustang II rack needs to adapt to a GM intermediate shaft

I have asked around, researched on the net and searched the H.A.M.B. but don't have the eloquent solution to my problem I am looking for.

I am trying to solve a steering shaft issue in my '56 Chevy shortbox. I can only chip away at it as funds allow as I have a nestful at home, and frankly my build is not a billet build (I love the eye candy, but can't afford the champagne on my beer-budget). Anyways, I have a Mustang II rack mounted on a TCI cross-member and a Buick Regal tilt column in the cab. I picked up a collapsable intermediate shaft from the auto-recyclers today for $20 in perfect shape, out of an '02 Astrovan. Damn, it looks perfect - small and sleek, not as big and cumbersome as some stock systems like the S-10 shaft, etc. It has no rag joint, but has two universal joints.


Compressed length is 15", fully extended to a hair beyond 21". One end slides onto the end of the column no problem, being a GM product I had hoped as much, but as I figured, the other end does not match. The mustang rack does have the 3/4 - 36 splined shaft and the intermediate shaft does have a 3/4" splined hole, but either the number of splines is different, or the flat side of the shaft isn't the right size/shape, etc . Everything else looks great and I'm 90% of the way there. Any ideas out there??

 

Get an after market straight mustang adapter that goes on the rack and have it welded to your new unit. I would put a steel dowel in your new part and into the adapter for additional strength and would never have any problems with it. With a hand grinder you can champer the parts to be welded and is what I have done in the past. It should be a cheap fix.

 

If the solid part of your pictured shaft is 3/4 DD you can buy a universal joint from a hot rod parts vendor that will connect your shaft to the rack.

 

Just brain storming here but. I wonder if the intermediate shaft from a late model Ford van would have the same spline arrangement as the MII rack. If it did and had a female 3/4" DD you could knock out the nylon keepers and build the shaft you need.

But, the first thing I'd do is get a big magnifying glass and examin buth male and female splines on the parts you already have. I once had a similar problem and upon closer inspection all I had to do to get the parts together was file the flat spot two more teeth deep.

 

Borgeson joint 3/4-36 x 3/4 DD retail about $71.95 your spline count on the shaft is probably 3/4-30 GM used both 36 and 30 spline counts on there boxes

 

Borgeson will have the adapters, Ididit uses all GM columns, and they adapt them to Mustang racks, They sell Borgeson, I don't know how their prices stack up against a parts house, in my experience the same. Be careful with the welding on the column, it is a good idea to pin them or in some cases do both, some items may be heat treated? It would be good to ask at Ididit, they are great people and even though they sell a lot of candy, some of the stuff they sell can be used by good old hot rodders as well.

 

borgeson and flaming river both dont recommend welding their joints they have the set screw and lock nut combos and you are correct on the pinning it the only one that involves this is their 3/4 smooth bore joints, hope this helps-Paul

 

Thanks for the responses. All good information and worth considering. Yesterday I spend a couple of hours doing a little more research and talked to a couple of vendors like Borgeson, CCP, Langley Old Car Center, etc. The Astrovan u-joint has 3/4-30 splines, but no one makes any kind of coupler with 3/4-36 female on one end to go on the rack and 3/4-30 male to slide into the u-joint on the intermediate shaft. The closest/best I have been able to come up with so far is a Borgeson coupler with 3/4-36 female at one end and 3/4-smooth female at the other end. I suppose I could cut off the input shaft from the Astrovan box use it to make my own adapter, but seems like a waste of a box to do so. Also, I have learned that we cannot weld any steering components in BC - automatic fail during an inspection, so pinning it together will have to suffice. I have 18" between column and rack and the shafts length is 15"-21", so whatever I add has to be small else I will completely lose the collapseability of the shaft.

I think when you see the shaft, you can see why a guy might like to use it. It's a little different than what you usually see and looks relatively stock.


A buddy thinks I am banging my head against the wall and will end up going the borgeson route, but I'd feel like I had given in if I went that way. Besides, I just like the look of the GM shaft, like the collapsable safety factor, dont want the added expense of the Borgeson parts. He may be right. In the end that just may be where I end up, but I if I do, I will take the scenic route to get there. Any other attractions or viewpoints to go to on my way there??

 

Just a thought: get a ford (t-bird, I think) lower u-joint assembly that fits your rack, take it apart and swap the lower knuckle part from the ford u-joint for the one that's on the GM u-joint. Not sure if the spider joints are the same though. Likely not, right? Maybe worth a look?

 

If the T-bird shaft has a DD female shaft on the lower end, that's the one that should, (in theory) slide right on the DD male shaft from the Astrovan as I suggested earlier.

bc woodbutcher, major respect from me for trying to solve the problem without ordering the solution out of a catalog! I ended up modifying an '84 Reliant shaft to go on a slip joint from a '75 Opel (of all things) to come up with a clean shaft to run between a '39 Ford column and a Vega box. My total investment was something like $10 and 2 hours work after a couple weeks of looking at parts and trying stuff in my spare time. The net gain was a super sano shaft with 2 joints, a rubber vibration damper and a slip joint all without having to order it from a catalog. The money saved was very important to me at the time but the satisfaction of doing it myself was, like the commercial says, priceless.