TRW steering box spline count?

[The Big Bad Wolf]

I've tried to search this but couldn't find anything. Does anyone know the spline count on a TRW steering box?

Thanks in advance

[Steve Davis]

I've tried to search this but couldn't find anything. Does anyone know the spline count on a TRW steering box?

Thanks in advance

If you mean the steering input shaft, pretty sure that's 36. AFAIK, the original VW, the TRW and all of the 'equivalent' mfr's follow the original VW spec on that. If you mean the inside worm-gear, I don't know.

Here's a link to a part that spec's it..and below that, some u-joint couplers that fit it.
https://dunebuggywarehouse.com/colle...-set-17-2584-0

Steve, FV80

[The Big Bad Wolf]

I bought a 5/8 36 spline u joint from jbugs and it a hair too small and the splines looks bigger on the joint than the output shaft on the steering box.

If you mean the steering input shaft, pretty sure that's 36. AFAIK, the original VW, the TRW and all of the 'equivalent' mfr's follow the original VW spec on that. If you mean the inside worm-gear, I don't know.

Here's a link to a part that spec's it..and below that, some u-joint couplers that fit it.
https://dunebuggywarehouse.com/colle...-set-17-2584-0

Steve, FV80

[Steve Davis]

Hmmm... sorry. I've bought a few from theSamba.com.. but mine were always ATTACHED to steering boxes. All of the ones I've received have fit properly .. except maybe for one.. that I have never been able to DETACH from the steering box shaft. It's PROBABLY the same.. just rusted so badly that I haven't been able to get it off... trying intermittently for some 6 months . (thankfully, it was just a spare.. I don't NEED it at the moment.)

Not sure where yours came from.. TRW did make SB's for other models of VW. I think the one "we" use is the OLDEST model, but they also made some for later models of VWs.. type 2s and 3s and buses. Maybe you have one of those?

OH.. you say 'a hair too small'.. those things DO fit *TIGHT*!. If you have one of the CHROME ones, I would be suspicious that you might have some difficulty if so... the chrome plating would make it a LOT tougher for a proper fit. Have never ordered.. or even SEEN a chrome plated one. Those fine spline teeth are NOT going to be forgiving fit wise.

Steve

[BLS]

I bought a 5/8 36 spline u joint from jbugs and it a hair too small and the splines looks bigger on the joint than the output shaft on the steering box.

36 splines does not mean they are the same as a VW steering gear shaft, but you would think that's what jbugs would be selling. I'd contact them and if they say yes, then it's just a tight fit like Steve points out.

[Hardingfv32]

I have been building FV''s for 35 years and I don"t ever remember the steering shaft interface being as easy as buying a 5/8" universal. You always have to adapt a stock VW unit. This is a metric german piece after all.

I measure the OD of the steering splines at .634",

Brian

[The Big Bad Wolf]

I measured about the same. The inside of the u joint is 6.14 and the output shaft 6.36

I have been building FV''s for 35 years and I don"t ever remember the steering shaft interface being as easy as buying a 5/8" universal. You always have to adapt a stock VW unit. This is a metric german piece after all.

I measure the OD of the steering splines at .634",

Brian

[BLS]

Clearly not made to fit the VB bug steering box spline for the early beetles. Ones I have used are split, and tighten with a pinch bolt.

6.36 - 6.14 = 0.22, almost a quarter inch off...

[pacratt]

6.36 - 6.14 = 0.22, almost a quarter inch off...

You're actually seeing .636" - .614" = .022" (Still too considerable to hammer on).
Glenn

[Steve Davis]

Found this on thesamba.com... a great place to source old parts .. but buyer beware - you have to make your own decision about EXACTLY which parts you want to buy.
Pretty sure that THIS one will provide both ends of what you seek...

https://www.thesamba.com/vw/classifi...php?id=2674831
Steve, FV80

[The Big Bad Wolf]

I've bought stuff from the samba years ago with no problems. I have a coupler already. I need to lean the steering box backwards enough that the steering shaft is above where it needs to be. So I'm looking for an actual steering u joint to mitigate the different angles.

Found this on thesamba.com... a great place to source old parts .. but buyer beware - you have to make your own decision about EXACTLY which parts you want to buy.
Pretty sure that THIS one will provide both ends of what you seek...

https://www.thesamba.com/vw/classifi...php?id=2674831
Steve, FV80

[Steve Davis]

I've bought stuff from the samba years ago with no problems. I have a coupler already. I need to lean the steering box backwards enough that the steering shaft is above where it needs to be. So I'm looking for an actual steering u joint to mitigate the different angles.

As mentioned by Brian, your best bet (probably ONLY option) is to get whatever uj you need for the Steering wheel end and WELD the 'box end' to a coupler that DOES fit the steering box. That's what I did as well when I needed to modify the angle on my car (Vortech). Suggest you tack weld it first and then check all angles from end to end before welding permanently... just in case you need to cut the tacks and move it again. Just make sure you have a GOOD STRONG weld there before using it in earnest :-).

Steve

[FVRacer21]

Okay - I did not see the answer above so I counted the splines on a TRW box and the number is..........63. (not not 42)

I get the spline diameter as between .642" and .640"

I do not believe the VW part that goes on is splined. When clamped down it locks on the shaft splines.

I had one that was loose when the bolt bottomed. Fixed it by putting a shim in between the shaft and the clamp

What was perfect was the Castrol LMA METAL can (remember them) cut into pieces.

If I ever get my lathe working - this is what I will use - following Steve's instructions. This way you can index the steering wheel without having to cut/drill and reweld.

(Here is one supplier)

Splines Shaft

Splined Joint (you can get with one end smooth 3/4" for through bolting or welding)(found a 5/8")

ChrisZ

PS - of course the Helicopter joints are much nicer - but at 3 - 4 times the price....

[Hardingfv32]

You can get a 5/8" id split (uses pinch bolt) and splined joint. Not saying the splines are going to be of any value. Yes, the VW part does not have splines.

So in theory you should be able to clamp down on the steering shaft splines.

That said, it is important to note that the VW units rely on the pinch bolt to clock the universal into a fixed position. The bolt hole in precisely machined into the joint collar so as to mate perfectly with the recessed slot in the VW steering shaft. As long as the pinch bolt is in place the steering column stays locked in place to rotational forces. This is a fail safe feature you are not going to get with an after market u-joint.

Brian

[pacratt]

Made this piece about 35 years ago and still using it. Bore is a tight fit to the box shaft and the pinch bolt engages the groove (or flat) on the box shaft for anti-rotation (timing). The other end is turned .625" dia. snug fit for the 3/4" Apex U-Joint and I use a 5/8" steering column.
I've seen a very similar part made with a short 5/8" shaft welded to the steering box side of VW coupler (donut ears removed).
Glenn

[BLS]

You're actually seeing .636" - .614" = .022" (Still too considerable to hammer on).
Glenn

Dang. I blame youth.

[CARSHouston]

I measured and did research on this last year, the actual size is 16mm x 62 spline. NO ONE makes a u-joint this size.

You can make an adapter like pacratt did, but I just cut off the standard spline and adapted a Woodward splined stub to the steering box and now use a Woodward u-joint and a splined shaft to the steering wheel. I'll post a photo on Friday.

I spoke to both Borgeson and Woodward, Woodward said they would make me u-joints if I wanted to buy the broach, I didn't think I could sell enough to make it pay for itself.
These are the weld-in splined stubs I used. 7. Steering Universal Joints, Splined Couplers and Shafts.pdf (woodwardsteering.com)
George

[Steve Davis]

Persuit to this thread, I did some checking and found an original VW Steering box and a TRW steering box.. AND an original coupler for the path to the steering wheel. See the picture below.


There are definitely SPLINES on both the SB input shaft as well as the coupler to the 'rag joint' - that's the way both were, in the original VW vehicles. The coupler is NOT smooth. I didn't think that VW would have ever left a smooth surface on either one. The flat, is a 'backup' indexer and allows for a TIGHT TIGHT clamp. I also COUNTED the splines and I got 62 - I counted twice, but it's still a tough count . I didn't bother trying to count the inside splines of the coupler, but am confident that it's a match. I have 're-coupled' a few times when I had to remove the steering box to change the beam (somehow the blasted thing got BENT??). 1 spline would make about 6 degrees of steering wheel offset.. and I could go 1 spline either way and still stay 'on the flat' for the bolt.

I have personal experience that the flat only keeps the shafts from spinning all the way around. If the shaft slips on the splines either end, the vehicle will be dangerously undriveable. The flat/bolt would only keep the shaft alignments 'in the neighborhood' so you could probably get it off the road without incident.

Steve, FV80