This is number 6 in a series of studies of the Improved Models parts, and the changes to them. So far there has been good results with the other parts studies already in progress. Thanks to everyone for their input. This study is about the Tie Rods, and Steering Connecting Rods (drag link) for the 26-27 models. I am fairly well certain there are no changes to the tie rods. I will show a photo of the style used in 26-27, but I believe it is the same as earlier cars. It is the type that has the ball/stud that acts as a clamp for the adjustable end of the tie rod. It should also be correct for the Ton Trucks (all years). If there are any changes to the tie rod I am unaware of please let us know. I will also show a photo of the 3 different drag links that were used on the 26-27 cars and TT trucks. I showed them in the photo in order of length and not in order of issue. It shows the different lengths of the drag lengths better that way. There are three lengths I will speak of, 30-5/16 inch , 31-1/8 inch, and 30-7/8 inch. The first one of 30-5/16 was used from 1919 to 1925 on cars and TT trucks. The reason I mention it is because I think it is also the same one used on 26-27 TT trucks. The second one is 31-1/8 inch long. It was used from start of Improved model production till 10/7/25. It is the longest of the drag links. Then the third one is 30-7/8 inches long. It was used form 10/7/25 till the end of production. If you notice, the 31-1/8 (longest) drag link, was only used 2 months and 7 days. In my opinion I feel like the longer rod was a mistake. It probably was too much of a change in length, from the 1925 and before version, and did not work well. If you notice in the photo of the three different length ends, It appears they just "split the difference" from the earlier one (25 and before)and the longer one (introduction till 10/7/25) drag link. Not real precise engineering but it looks that way to me. I have gathered these lengths from various places as well as the online encyclopedia. One other thing I remember from conversations with other older Improved car owners, is that they would change the long rod (31-1/8) to the middle length rod (30-7/8) even back in the day. They said it helped the steering. ????. That makes me think the long rod does cause some problems with the steering.
Style of tie rod end used. This style was also used for years before the Improved models. as well as Ton trucks.
overview of the various drag links and tie rod.
A good view showing the various lengths and how much they changed. They are in order of length and not order of issue.
Thanks for information on drag link lengths. - Very important when you are trying to assemble a Tudor 26 from parts like I am.
It gets even more complicated, when the car was originally assembled in the Copenhagen plant, as at that time (1.quarter 1926) they were using many parts originating from England, of which many were different from the US ones.
(P.S.: Also thanks for your opinion on my frame no. 15,007.600.) - Niels
Niels, We have enough issues and problems here in the US trying to get them "correct" but you "over there" and down under" folks really have problems. The old saying, "how can we get it right, if Henry never built them right" applies here. On top of that He also took them apart to ship to the other side of the world, did not send all the parts, so your factories had to make their own versions of the parts that were missing. No wonder your steering wheel is on the wrong side of the car. One more note as to the drag link lengths. I did not mention any of the pre 1919 drag links. There were several more lengths from that time period. So when searching for the correct lengths for the 26-27 models you may find other lengths than the three I mentioned. There also was aprox. a 1/8 inch tolerance built into the specifications for the links. For example, the 31-1/8 inch link could be as much as 31-1/4 inch in length because of the tolerance allowed in manufacturing them. Knowing about the tolerance may help when looking for the parts.
You can tell whether you have the right length if when the wheels are pointing straight ahead, the pitman arm is straight down, not to one side. If the link is too long, the pitman arm will be to the left of the car, and if too short to the right of the car. (on right hand drive cars, the direction would be opposite the above)
Norman: Good info. The measured length is good to know when looking at a swap meet for the parts. Then your "observation test" will make sure you found the right one. I guess that a person could also have the drag link removed, and the pitman arm straight down, with the wheels pointing straight ahead, (with correct toe in). And then measure center line to center line of the pitman and drag link balls, to come up with a correct measurement.??.
Thank you for the information. Here I thought the wrong length was put on my 1927.
I just measured the two drag links on my cars and the three spares I have. Don't know if any one were ever filed, but likely not. My parts are 90% 1919-27 stuff found in Sweden, the rest imported from USA.
The shortest one was 30.24" long.
Then there were two 30.4" long, one of them still rusted stuck to a 1919-25 front axle assembly.
Then one 30.55" long on my '26 primitive pickup
and one 30.82" long on my '27 roadster.
My cars are put together from various part sources and not correct. Good advice about having the pitman arm vertical when going straight, I'll check carefully and may change links.
Since I found more variants than were available in the USA I suppose a couple of my drag links may come from european drop frame models. The length of the drag link on 1925 DF models was likely different from the '26/'27 DF models and may have changed during production judging from US production.
Roger, I only listed the three for use on 26-27 models to help keep confusion down about the 26-27 drag lengths to use. There are also several other lengths for the earlier models. And with the aprox 1/8 inch tolerance in manufacture, there is no real accurate measurement. I will try to list all the measurements this evening along with their tolerance range when I get back to my notes.
I looked up all the lengths I can find.
early cars till 9/19/14 30.687 (30-11/16)
9/19/14 till 10/19/14 30.687 (30-11/16) to 30.750 (30-3/4) A tolerance for manufacturing purposes is the reason for two measurements
10/19/14 till 10/2/17 31.062 to 31.125
10/2/17 till 5/19/19 30.938 to 31.062
5/19/19 till start of Improved Models (Aug 1925) 30.312 to 30.438
Start of Improved Models (Aug 1925) till 10/7/25 31.125 to 31.250
10/7/25 till end of production 30.812 to 30.875
These measurements are taken from the online encyclopedia, service bulletins, and a few other places I can not remember right now. It may not be all the lengths but it is all I have for now. Maybe this will help and not confuse things worse. I just about have the next thread ready for discussing the steering columns (I still need a couple days to work on it). I think the drag links have been discussed fairly well. Thanks again, for everyone's input