Union Pacific Passenger Car Trucks

Index For This Page

This Page was updated on February 10, 2016.

(Return To UP Passenger Cars Index Page)

Diner Trucks

The following comes from Bob Webber, as posted to Trainorders.com, June 14, 2013:

Orders to Pullman from the UP often included the term "Railway Supplied" and usually included trucks. Meaning that Pullman (or whoever) would build the car, and UP would supply a plethora of parts (not just trucks, but all sorts of equipment). This wasn't uncommon, but UP did it more than most.

Another aspect of this is on Diner cars was that the kitchen truck and the dining truck were often vastly different (in terms of springs and often in terms of other supporting metal work) - the weight on the kitchen truck was much more than on a dining truck. The kitchen end was typically - by far - the heaviest supported passenger portion on a train, while the dining side was usually one of the lightest. The weight difference made for an interesting engineering problem, and railroads had to be very careful to put the correct truck back under the correct end of the car.

Cars in the same class had to be weighed individually, and the trucks modified as a result (cars could be several thousand pounds different). Different or more springs, varying plank structures, etc. all came into play.

Streamliner Coach Trucks

In 1941 UP had three 48 seat streamlined coaches for use on the 'City of San Francisco' and the 'City of Los Angeles' (COSF AND COLA). Two of these cars were the "Pasadena" and the "Boulder City". I was informed that originally these cars had UP triple bolster trucks (but in "The Streamliners" book a photo dated 1954 shows these two in Portland, OR, riding on CUDO type trucks). Can any one tell me how many trucks styles did these cars wore through the years and when did these trucks were installed? (Karl Gasner, email dated April 6, 2006)

Originally, they had LFM-Atcheson U-43-R trucks. UP updated many cars with GSC 41-CUDO-11(CIB) trucks. The earliest outside swing hanger trucks used by Pullman were on the UP Train of Tomorrow in 1947. After the 2-axle triple-bolster truck models (U-43-R, U-43-HRV, 43-R, IC-43, RI-43, SP-43, etc.), Pullman switched to the GSC 41-HR and 41-ER starting in late 1937. After that (for UP), GSC 41-CUS in 1949. After that came the GSC 41-CUDO-11 models starting in 1950 (for UP coaches). The Canton *forged* I-beam equalizer GSC models [41-CUDO-11(CIB)] started appearing in 1954. I would guess that PASADENA and BOULDER CITY received new trucks also in 1950, and also that the previous trucks were the originals, because of the dates older trucks were introduced. One other car, MONTGOMERY STREET, later numbered as CNW6148, was Plan 7444 (like PASADENA), but it was sold to CNW, and was likely not retrucked before being scrapped in 1958. (John M. Fiscella, email dated April 7, 2006)

Three Axle Trucks

The following comes from Steve Orth, via an email dated August 19, 2000

The following lightweight, post 1941 Union Pacific headend cars were equipped with three axle trucks:

Postal-Mail-Storage is the UP designation for an RPO
Postal-Storage is a baggage car built for mail
Baggage is obvious

Data taken from:
Union Pacific Railroad Co. Research and Mechanical Standards,
Passenger Car Diagrams

Swapping Trucks

Bob Darwin wrote on September 21, 2004:

To my knowledge the 5000-5006 and 6000-6008 cars did not have their trucks changed out to 41-CUDO until 1958 at the earliest, and probably not before they were shopped and rebuilt in 1959. This time frame also corresponds to when the UP decided to paint thier passenger car trucks Aluminum instead of Harbormist Gray.

Regarding the 1941 Pullman 6-6-4 and 4-4-2 sleepers, I believe these cars never had their original trucks replaced, and I can say this with some confidence as I have never seen any evidence to the contrary. Over the years, I have compiled, printed and examined dozens of photographs of these cars, including several taken after they entered MofW service during the 1960s, and none show them equipped with anything other than their original Pullman trucks.

After 1949

Dick Harley wrote on April 20, 2011:

On Tue Apr 19, 2011 Michael Bishop asked about 41-CUDO-11 trucks, "Is the type of truck Union Pacific order for their cars or did they do a swap out of trucks at some point in time?"

That would be Pullman Company truck code 41-CUDO-11 trucks on UP cars. And the answer to the questions are yes and yes.

In case you don't know, 41-CUDO-11 means: 4 wheel, single bolster - 9'-0" wheel base, 14-1/16" wide journal pedestal (unique to UP), Disc brakes, Outside swing hanger - 6x11" axle journals.

The 41-CUDO-11 truck was introduced on UP passenger cars with the arrival of the "Pacific" series sleepers in late 1949. All new UP passenger cars with 4-wheel trucks delivered after that also had 41-CUDO-11 trucks when new. Of course, not all 41-CUDO-11 trucks were created equal, so we nit pickers will note differences among those trucks.

No other 1949 delivered cars had 41-CUDO-11 trucks. The other 4-wheel truck cars built in 1949 had the 41-HR-11 truck.

After 1949, the next UP cars after the "Pacific" sleepers to have 41-CUDO-11 trucks were the PSCM 44-seat chair cars (5401-5445) built in 1950. Next were the ACF 44-seat chair cars (5450-5457) built in December 1953.

Some earlier cars did receive the 41-CUDO-11 trucks in swap outs in the mid-to-late 1950s and 1960s. You'll need to check photos for that. There may be shop records of those changes, but I don't know who has them.

A great article by Pat Wider about lightweight passenger cars trucks appears in "Railway Prototype Cyclopedia - volume 6".

Steve Orth added:

All cars delivered *after* the Pacific sleepers were delivered with 41-CUDO-11 trucks. There were cars delivered in 1949 that were not equipped with the these trucks, such as the 4800 series Diners, the 5000 series Cafe-Lounge cars, and the 6200 series Lounges.