Saginaw Steering Boxes

I’ve replaced the manual Saggie with a power steering box from, I think, an ‘80s Chevy, maybe a Camaro.

This is on an intermediate CJ5, with steering bits from a ‘72. The u-joint that attaches to the box has a 36-spline end, with a bolt and clamp. The bolt was in a ‘slot’ in the manual input shaft, but my new box has a slight groove and also a flat on the shaft.

Both have 36 splines but the joint refuses to slip onto the new box. I did have to pound it off the manual box, so maybe it’s just too snug…

Is it likely that these parts are compatible? Or is there a different u-joint needed for the input on the PS model?

Anybody know?

Jon B.

 

Typically power and manual Saginaw boxes have different diameter inputs. Just because the spline count is similar does not mean the diameter is the same so I’d start by measuring that and comparing to your old box. Typically having to tap off the shaft from the input is common but if you had to pound it off that sends red flags of improper fit or damage somewhere. Sounds like you may have mismatched parts. just as an aside I’m not a fan of rag joints. Seen way too many fail. Had one fail on me in a parking lot after a long trip flat towing my CJ to the Oregon dunes. Pulled into the parking lot, tried to make a sharp turn, and steering wheel just spun in my hands. Never again.

 

X2. the diameter of the two slip joints are different for sure. You can buy a new replacement slip joint repair kit for a power steering gear and still use your shaft that worked for the manual gear.

 

Well…

I failed to mention that the spline of each box measures 0.730” with a caliper - on the outside of the spline. That led me to think they’re compatible.

I did find that Vintage Jeep Parts has two u-joints: one for manual steering, and one for power steering…

The joint came off with mild persuasion. More than tapping, less than pounding on it. After fifty years, I figured that was normal.

The joint isn’t a rag joint. It’s a slip style with the square ‘blocks’ in channels. I can’t remember the actual name. It needs a new rubber boot, anyway. If I have to replace it, it’s a $50 part.

Thanks for the info!

Jon B.

 

Jeep Saginaw manual vs power used different splined bellcouplers. Otherwise the bellcouplers are identical.
It’s either the 30 or it’s the 36 spline bellcoupler.

 

Bell coupler

Good luck on the boot. I rebuilt one a couple of years ago and the boot flange was too thick for the snap ring. Not only that, but the boot was made of some sort of hard plasticy substance that rips at the drop of a hat.

To my knowledge, there are two input shaft sizes. The larger one has 36 splines, the smaller 30.

Some joints have a blind spline. If so, insure it is aligned with the blind spline on the box. If the box doesn't have one, then the coupler won't fit.

A blind splined coupler won't "slip fit" onto a non blind spline shaft.

 

X2. Been a while, now that I think about it the difference was in the spline count rather than the diameter of the shaft.
But I used a steering gear from a 79 or 80 cj7 with the slow ratio. So I just ordered a new bell coupler rebuild kit for the CJ7 gear. As I remember when researching what steering gear to get I think some gears from the pick-pull cars and trucks may of had a different diameter input shafts as well. Plus some gears use the rag joints that may use a flat on the shaft, but the cj7 gear had the a bolt notch the same as my factory manual steering gear. After all it's been 10 years, I just don't recall all the details.

 

After looking at my old notes I had encountered the fact that my manual gear shaft had about .730 diameter and 30 splines, where as the cj7 gear had just a fraction bigger shaft (maybe about 3/4) and 36 splines. Only about 020 bigger. This is likely why your manual gear bell coupling will not fit the new power steer gear. Wish my notes were more detailed so cannot be absolutely sure. I did not record every measurement I encountered on various gears at the time

 

When I was doing my Saginaw steering years ago, I spent some time wondering around a salvage yard looking for the double D shaft assemble GM used to connect the steering collum to Saginaw box. I found a good assembly which included the correct u-joints for attachment to both the steering collum and Saginaw box. The double D assemble is actually a slip joint (part of the collapsible steering design) which makes it easy to install or remove. New assemblies can be found online.

 

What old fogie is said X2.
I measure genuine Jeep manual 30 spline at .730
I measure genuine Jeep power 36 spline at .780

 

Ok. My ‘new’ spline is .730”, with what appears to be the GM 26-spline with the flat. The groove is fairly shallow, compared to the notch on the manual input shaft. The Jeep power steering coupler ain’t gonna fit, either.

Summit - and Lee Power Steering - have rag joints that should fit this power box. That opens another ‘can of worms’, though: how to connect the shaft to the rag joint.

Perhaps I’m off to the local salvage yard for a shaft that can be welded onto the stock Jeep shaft. Gotta love these mix & match builds.

Jon B.

 

Here’s what the input on it looks like (well, OK, this is the actual shaft):



Jon B.

 

Yeah I don’t know much about GM parts,
Way too many to keep track of.
Once you decide upon going to a TRANS-MAKE build. (using non Jeep components)
Then you essentially have to know about everypart that was ever manufactured for any vehicle.
That’s way past my grade of pay and…
That’s why I try to keep my builds 100% Jerp CJ 1941-1985. That about my limit of what I can keep in mind.

 

80s full size chevy vans have a two u joints on the box connected by a short shaft easy to cut and splice into an existing shaft.

 

Borgeson and Flaming River makes nice compact u-joints in all kinds of configurations but you pay for them. Summit racing might offer some under their house name, not sure but worth looking into. A little more bulky but I’ve been known to use pto shafts and joints with replaceable U-joints.
I like using steering gears from CJ’s but more commonly full size Jeeps as the ratio and strength works well.
For years I ran a steering gear from an ‘81 Firebird turbo car. Very quick ratio. Great on the trail and when racing but very twitchy on the road. I didn’t let anyone else drive it. Be careful what application you source your gearbox from.

 

I have a GM style rag joint on its way from Summit. Brother-in-law has a ‘79 Caprice with the shaft intact. Too weird, as that’s exactly what I used as the filter when perusing the Summit listings (there are hundreds of joints & connectors).

The shaft just fits between the shock mount and the power steering pump, with almost no clearance. It’s probably gonna work but won’t be easy.

Jon B.