Not a CAT D7

by Mark Sigrist and Jeff Rowsam “That is not a Caterpillar D7” was the subject line of an e-mail I received from my friend Jeff Rowsam one Sunday morning. Jeff…

by Mark Sigrist and Jeff Rowsam

Combat Engineers inspecting recently captured Soviet copy of American dozer in the A Shau Valley. Note M48 tank and the defoliated trees in the background. Photo courtesy Engineer Magazine, July-Sept 2007. Engineer Museum, Ft Leonard Wood. Used with permission.

“That is not a Caterpillar D7” was the subject line of an e-mail I received from my friend Jeff Rowsam one Sunday morning. Jeff went on to write: “Hi Mark, I opened my latest issue of Military Vehicles tonight and read with great interest your article about Dave Flinn’s adventures in Vietnam [“Operations into the A Shau Valley, 1968-69,” MVM, June 2019, no 203, pp 26-30]. Nice article. I am glad I got to know Dave a little bit when we were on the 2017 MVPA Route 66 Convoy together.”

Jeff spent his working career with Caterpillar Diesel Engines and Machines. His e-mail continued, “As a Caterpillar guy I didn’t get past the first photo in your article and said to myself, ‘Nope. That is not a well-worn D7.’ You may be interested to know that is a captured Soviet copy of the CAT D7.”

Soviet copy of American dozer captured in the A Shau Valley. Note the dirt packed in the carriage. Dave Flinn

Jeff explained, “You know, they [the Soviets] copied everything from 1930s on through WWII. I can tell by the weird rear-mounted cable control for the dozer blade that it is the Russian clone. Also, the machine has the standard Russian metal cab with the three windows in back.”

Well, that got my attention, so I went back to review the few photos that Dave was able to bring home. Sure enough, I found two more in that sequence.

Interior view of operator’s station inside the cab of the Soviet copy of American dozer captured in the A Shau Valley by Combat Engineers. Dave Flinn

Jeff was right. It is not a Cat D7. It does bring up a topic that never received much publicity, however. Dave told me that during their engineering operations in Vietnam, they “found” a “Chicom” dozer. He never told me the whole story of where or when it was captured or what ever happened to the equipment.

Jeff shed more light on the story:

“Now it gets interesting. Somewhere in my military history files I saved an article from a US Army Engineer history magazine years back. It was a first-hand account by Army Engineers in Vietnam combat operations in Northern I Corps.

“During jungle clearing operations, the engineers discovered and unearthed several buried and well camouflaged Russian artillery pieces, Russian trucks used to tow the artillery, stock piles of ammunition, and a track-type diesel bulldozer that the NVA were using to build roads from the Ho Chi Minh trail from Laos into Vietnam. The enemy did most of their trail building with human pick and shovel labor. That meant a diesel tractor dozer would be rare in that region. The engineers were not sure what they had. I suspected that the tractor in Dave’s photo is that captured machine.”

This Russian copy of CAT dozer undergoing major repairs in Budapest Hungary, was photographed in the late 1990s. Jeff Rowsam

An excerpt from an article by Gary Hollands and Wil Nelson in the publication, Engineer (July-September 2007; used with permission by Ft Leonard Wood Engineer Museum) provides more detail:

“While clearing vegetation…in the A Shau Valley, the 59th (Engineering Company – Land Clearing) discovered a Russian bulldozer that the NVA had abandoned when it fled the Valley in May. The dozer had a broken clutch, so the soldiers towed it along the perilous one-lane road carved through the steep mountains from FSB Rendezvous to FSB Cannon. There it was placed on a lowboy trailer and hauled back to Gia Le. This dozer was of American design but had been manufactured in a factory shipped to Russia during World War II as part of the Lend-Lease Program.

Right side of a Russian copy partly dissembled on a job outside Budapest, Hungary, in the 1990s. Any CAT mechanic will recognize how similar the copies are to their American counterparts. Jeff Rowsam

“Back at Gia Le, the dozer was repaired and made operational. The dozer’s clutch throw-out bearing was replaced with one from a five-ton dump truck. That replacement not surprising, given the Army’s habit of using common parts in many vehicles over a long period of time. That the dozer was an exact replica of an American Lend-Lease dozer was evident from the numerous nameplates copied on various parts of the equipment, including one on the right-hand side of the engine block. The casting duplicated everything-including the fasteners that secured the plate to the engine block-except the lettering and numbering on the nameplate.”

The article included the original photograph of the captured Russian machine. Some sharp-eyed study and comparison of Mr. Hollands’ photo and the photos taken by David Flynn in the MVM article indicate that these are, in fact, the same machine. Damage at the cab rear window frame seen in both photos confirmed the identification.

SIMILAR VEHICLES

Jeff wrote a bit more: “In my travels, I have examined a few other examples of the Russian S80 and S100 in my travels. I saw one being repaired on a job outside Budapest in Hungary once and saw another on display at a military museum in Hanoi in 2001. There are some Youtube videos that show them. They even sound like a 1945 CAT D7!”

Collectors familiar with the iconic WWII vintage D7 will recognize the similarities in the photos.

Left side of the Russian copy of a CAT dozer outside Budapest, Hungary. Jeff Rowsam

We never know what back stories may lurk behind old photos or tidbits of remnant past conversations. In this case, we were lucky by chance to expand our knowledge on the important historic military vehicles we find so fascinating! As the 591st Engineers would say, “Drive On.”

This is a view of a radiator of another Russian Machine in the outside display of the Vietnamese Air Defense Museum, photographed in Hanoi in 2001. The Russian company logo is on the front and the side of the radiator shroud where it would have said, “CATERPILLAR.”

Jeff added a bit to his note: ��While sorting some old files in the CAT Dealer office the 1980’s, I chanced onto a vintage article from a 1952 Caterpillar Dealer magazine with a photo of two CAT engineers in Peoria IL inspecting one of two Russian tractors ‘Captured by US forces in Korea.’ Guess what — my father was in the Combat Engineer platoon that captured one of them! I always heard that story as a kid. Dad said they thought it was an American machine. But the gauges were Cyrillic and the water pump was different than the D7’s the Americans had. He marveled that all the controls were the same. He always wondered what ever happened to it. The Cat article answered that question many years later. That captured tractor went all the way back to Ft Belvoir and then to CAT HQ in Peoria for evaluation. The ones captured in Korea look the same as the one captured in Vietnam. The Russians must have liked the design and built them for many years.”

Who knows where the Vietnam machine ended up?

Mark Sigrist was a US Army Vietnam Veteran and a retired USDA Forest Service Forester and Wildland Firefighter. He was a historic military convoy enthusiast who lived his dream in north central Idaho, sharing the land with abundant wildlife and very few neighbors. Unfortunately, our dear friend Mark passed away on 2 August 2020, after a courageous battle against cancer.