Rod ends for SBU shifters

Hmmm.....

My take is that load limit of the part is not too important. The force applied is basically aligned with the rod, via the metal ring of the joint, and not perpendicular to ring or rod (totally different situation). This means the plastic piece is a bushing, transmitting a (probably light) compression load from the ball stud center point into the ring, and longitudinally down the rod to the next ball joint, and onward as above. The ball end allows for angular movement of the joint/ rod, but keeps the forces centered. There is little or no force that would try and pull the ring off the ball stud, as evidenced by the lack of a "keeper" on the OEM part.

My bigger concern (and it is not a big one at all) is the bending strength of the connecting rod, to resist the compression loading (tension not likely to be a problem, no bending there). On my truck, the moonlighting M-B mechanic who installed the working gears while the truck was still in Belgium made a a linkage using a fairly small diameter threaded rod, and not even grade metric 10.9, at that. No issues whatsoever, I have looked at this and thought "I should do this up right", but when it works for thousands of miles, that task falls pretty low on the list (meaning: not done, not even thought about agaIn until now).

Take a look at the gas struts for hatchbacks, etc. Some of those have really high pressures, and rarely fail; when they do, it is usually loss of gas pressure. My RW1 drop sides have 250# struts, and they are not of massive diameters, rod or ball, and the only non OEM (after 35 years) one is the one I busted apart by doing something really stupid (sideways).

All FWIW

Lee

I agree - the load rating required in this application is probably very low. I was more curious about the range of motion, and the bulkiness of the McM-C parts, but they seem to be OK size-wise.

The Mercedes-Benz pieces just press fit together, but it isn't something you can do with your fingers. It would take a vise. That is why I didn't put mine together - I didn't want to lube them up and assemble them, only to have to possibly take them apart. Plus, the one ball has a ratty, pitted finish from rust (I think), and one of my inserts has cracked. The MB inserts have little to no 'give' and are quite rigid. It may be that they lose some of their resilience over time. Then the cracks appear, then they exit into the snow, or mud, or sand, or rocks.

I'm curious to see what MEREX sends - If they are the original pieces, or are they what A. Vos supplied to krietpiel ?

They are obviously up to the task, but I'm leaning towards the McM-C stuff, at least I intend to put an order in and then proceed to fiddle with those pieces, depending on the MEREX package.

The shift rods.

Both 10mm in diameter.
Two lengths -
A. 469mm (18 - 1/2 “)
B. 431mm ( 17 - 11/16”)

A little more information on the rods for these assemblies. I think that the two lengths that I mentioned above might literally only be part of the story.

Neil told me some years ago that the long rods were no longer available from the MB parts department, so the choice was either used pieces, or used and new pieces (but only the 'Short rods') pieced together with coupling nuts to achieve the length of the 'Long Rods'.

This seemed like a problem that could easily be solved with a competent machine shop. The conversation was a while ago, and I do not know if MB has stepped up and made a run of the Long Rods or not.

I'd want the one-piece Long Rod over the composite pieces - two less threads per rod to rattle apart. Also, no chance of the coupling nuts interfering with the other rod / coupling nut assembly.

In these photos, you can see two short sections of rod, attached to a shift plate (or console), that Roberto was working on. Two short lengths with one coupling nut attached. In this case, I think there are two PTO levers and one Lever for the Working Gears, but the short rod sections with the coupling nut would be the same, I think.

In the photo of the transmission assembly on the pallet, with the Working and Crawler gears attached, the two
one-piece rods look to be longer than the two measurements I posted above (18-1/2" and 17-11/16"). They also look like they might be a little larger than 10mm in diameter. It might be an illusion - The two rods on the milk crate look like they might be a close match to mine. It is hard to tell from looking at photos - a measuring tape would settle it in seconds. Their diameter looks about the same in relation to the rod ends, so maybe they are 10mm, but it would be good to know for sure.

So, if you (Ragnian) have the one piece Long Rods on your rig, could you please post up the overall lengths, the diameter, and the length of the threads ? (Once you pull things apart). I think I'd rather get them made as opposed to piecing them together. Unless I already have the Long Rods and just don't know it.

Thanks.

I am kind of a fan of the "brute force method", that is, just figure out what is needed and go knock it out, step by step. In cases like this, I think it is quicker and less brain strain than trying to finesse a solution with "proper" parts.

Faced with this problem myself (which I am supposed to be, see earlier post), I would get a set of ends and compatible ball end studs from our favorite source, and then drill/ weld/ etc as required to mate the ball studs to the shift arms. I would try for a lefthand/ righthand threaded pair of ball ends, to give the turnbuckle effect in the finished assembly, but that is not essential to the concept.

As for the rod, I would also order up a piece of steel tubing with an ID greater than the OD of the threaded rod ends of the ball joints, and a pair of grade 8 nuts (hopefully left & right hand threads), or possibly a pair of rod couplings, to match those threaded ends.

Cut to length, then (TIG) weld nuts/ couplers on each end, let cool, install, adjust. Done.

A trick on the welding: run a smaller diameter threaded rod through the tube and the nuts, add washers and nuts on each end, tighten. If cuts are square on the tube, this jigs everything up nicely.

Lee

What about this option:

Rierdge 8mm Inside Dia Rod End Bearing Self Lubricating, M8 x 1.25 Female Thread Connector Joint, SI8T/K Rod End Ball Bearing, 4 PCS

m8 1.25 thread. Not sure if left hand is available and you would need an 8mm stud to mount it.

The only possible issue I see with going with the larger diameter tube would be clearance. In some photos, the two rods look pretty close to each other, in others, not so much.

One of my rods has wear marks on it in a number of spots. Nothing major, but that could have come about when the two levers were in different positions - Working gears only, and Crawler Gears engaged 'on top of the Working Gears'. Or, both disengaged, and also the possibility that the rod with the marks was installed end-for-end at some point. The marks look to be in spots that would indicate that the two rods were rubbing against each other.

There are a lot of possibilities , however. The one rod could have been in a PTO linkage instead, and there are at least two different versions of the lever part of the equation. The photo of the pieces on the milk crate show two matching lever assemblies. Merex shipped me one of each, and I'm going to try and match them both to the Milk Crate type.
Also, I'd say it is pretty unlikely that my two lever and rod assemblies came from the same donor truck.

I'll see what MEREX sends to Ragnian and go from there. I think I'll probably go with the McM-C rod ends and weld nuts to the drilled-out lever arms, but I'll see.

Good information.
I checked on shipping to Bozeman, Montana,
and it didn’t compute.
It is good to see that the original pieces are available.

Images from the linked site.

It looks like DT and FEBI make aftermarket ends for mercedes trucks. Left and right thread. This is on ebay shipping from Germany.

This style here has the locking pin to keep the joint from popping out after years of operation.

An update, I got to this today and have some information for you but not all the information.

Cascade/Super-Crawler linkage rod:
19 Inches long
Rod diameter 12mm
Thread length 22mm
Thread diameter 7.75mm

The rod is hollow almost certainly, I have used a lot of 1/2 solid steel rod in the metal shop, this stuff does not feel like that and it is magnetic. So it must be hollow.






The rest of the story, I did not pull the working gear selector rod because I only have "right hand" rod ends and did not want to break something and not have parts, I just ordered the left ones from MEREX. As you can see in the pic above I went ahead and replaced the right hand one since mine was really tired anyway.

Since snow season is basically over here for the season, I left the linkage out for now, not going to need the crawler gears anytime soon I think. Will put it back in when parts arrive next week probably.

If you still need me to yank the working gear linkage I can then.

Another option might be Schussler, they have a bunch of MOGs being parted out, when I was there last month I bet I could have grabbed what you need. They must have at least 40 Square Cab MOGs for parts. Super great people! In my opinion in the same league with MEREX...I like both places a LOT!!!!

On the other hand some steel pipe, metric bolts left and right hand (Belmetric) and a TIG welder and you would be set.