The Stovebolt Site Forums The Shop Area Driveline 1950 3600 Drag Link replacement

As some may know from another thread I am in process of relocating the steering box on my 1950 3600. The relocation forced a review of the ball ends for the drag link and they are in need of being replaced. I reviewed the tech tip regarding the replacment of the drag link on a 3100 with one from a 54 version that has modern type rod ends connected to the pitman arm and spindle arm with tapered studs which sound like a reasonable approach . However, the information I have been able to find indicates that the 3100 and 3600 drag links are different. I assume the difference is due to the heavier expected load on the 3600.

I would appreciate any information others can share regarding a replacement drag link for the 3600. If the pitman arm and spindle bracket need to be machined with a taper to work I think I have a local resource that could do that.

I have seen a replacement link with fixed ends (non-adjustable) that appears to be setup for the standard orientation.

Unfortunately I need to move the pitman arm end to the inside of the arm which would require (I believe) the spindle end to come up from the bottom rather than down from the top which will not work. Idealy I am looking for a new drag link with adjustable ends so that I can adjust the orientation required to get the geometry of the relocated piman arm back to something close to the original design.

Totally unrelated to your 3600, but for my '37 I had a new draglink machined from some type of tool steel my uncle had, see diagram. I then used the tie-rod ends I have linked, they are a straight shank drop in replacement for the ball studs. No machining needed other then what you need to do to get the ball studs out. Again, this all for the 1/2 tons, but maybe you can get some ideas.
Tie-rod ends https://www.bowtiebits.com/store/st...amp;Category_ID=1&Sub_Category_ID=18

Joe H, thanks for the information and the link. Straight shank rod ends would make things easier.

Bartamos, thanks I had seen that thread and made my bracket for moving the steering box out similar to the one shown by Coach529. I believe in the thread he indicated that he flipped his drag link to the opposite side of the pitman arm but what I did not realize was that he also modified the spindle arm to allow the joint to come up from the bottom. I am hoping to minimize the changes to the spindle arm so something like Joe H described seems like a preferred solution for me.

I had a new drag link fabricated using rod ends and thread insert bushings from https://www.skysoffroaddesign.com/products/sky-byosk-001 and had the pitman arm and steering spindle modified to install their taper bushings to match the new type rod ends.

the resulting parts are very robust and I do not have any concerns about the safety of the system.

That is a good looking part, it should last a life time!

Did you give them the original part to use as a template?

Otto, I did not but I used the original center to center distance as the dimension to shoot for when determing the length of the tube with the ends installed about 2/3rds of their thread length. Given tha tthe original is not adjustable and the new one is adjustable it did not need to be too critical.

That's pretty nice. How much did they charge to build that?

I just made this one for my truck over the weekend using rod ends and swedge tubes from Summit. These are the same pieces racers use for their suspension so they're plenty strong enough for a drag link. And it's adjustable so I was able to perfectly center my steering wheel. Easy!

Matt,

Would you share the part info/ID's on what you used???

Thanks!

I had the rod ends laying around from another project, but these are they: https://www.summitracing.com/parts/fkb-jmx10t

They use 5/8-18 threads and have a 5/8" diameter hole in the ball. They come in both left and right-hand threads, so you'll need one of each to make your drag link adjustable. Be sure to check the description so you get the correct threads.

I used a 10-inch swedge tube: https://www.summitracing.com/parts/aaf-all57164

The swedge tube has 5/8-18 threads at both ends, one left-hand and one right-hand, so the ends thread right in and it's adjustable by simply turning the tube.

I also used jam nuts in both left- and right-hand threads. These secure the swedge tube so it can't turn once you've set it:

https://www.summitracing.com/parts/qa1-jnr10s
https://www.summitracing.com/parts/qa1-jnl10s

And, of course, safety washers so if the rod end fails, it doesn't pop off: https://www.summitracing.com/parts/mez-sw58a

You can source the 5/8" nuts and bolts locally. I used grade-8 nylock nuts but you can also use castle nuts if you drill a cotter pin hole through the bolt. I used 2.5-inch grade-8 bolts, but I think I'm going to take it apart and use 3-inch bolts with another safety washer on the other side of the rod end. It's not going to come apart, but that's the right way to do it.

Hope this helps!

Matt,

Information is greatly appreciated!

Thanks for sharing.

Otto, the parts from Sky (rod ends, thread inserts, and taper inserts) came up to about $160, I paid about $38 for the DOM tubing (12" so a lot more than I needed), and my machinist machined the tube, welded in the thread inserts, and machined the pitman arm and steering spindle for the taper inserts (also welded them in place) for $75 so all in it cost roughly $275. Pricey but it's robust and I like the greasable rod ends.

Matt, I considered taking your approach but was not sure about the rod ends as you used. Safety washers is a good idea but I was more concerned about the wear from being open to the elements creating the potential for the steering becoming "loose". Tod ends like that are very common on four link axle set ups and farm hitches but in those applications a little clearance doesn't really affect things.