Thomas

1981-1991

Thomas' Type D buses of the 1980s aren't exactly common survivors. Making matters worse, Thomas' VIN system of the 1980s is almost inscrutable, since no reference source is readily available. This analysis was scraped together mostly from observations alone:

1T7C3D481C1752772

Positions 1-3 and 11: Manufacturer and assembly plant

Whether Thomas ever built complete buses at its Woodstock, Ontario satellite plant is anyone's guess.

Position 4: Body length

Similar to Blue Bird, Thomas used model designations in this era where the first two digits were the same as the body length in feet:

Position 5: Type

Position 6: Engine

This list is incomplete, and probably has a few errors...so take it with a dash of salt:

Positions 7-8 and 12-14: Production sequence

The sequential number in the VIN is the five-digit order number of the bus, assigned prior to manufacture. It also appears as the leading portion of the lengthy body identification number (i.e., "65980-28901-RE-3885S") engraved on the certification plate of Thomas products.

During the 1980s, Thomas order numbers progressed from the 40000s through the 90000s. Order numbers were assigned to all buses, including conventional models built on outside chassis. Thus, most were never used in VINs, and any list of Thomas VINs will have numerous sequential gaps.

Position 9: Checksum

0-9 or X, calculated from the other digits.

Position 10: Model year

Thomas appears to have aimed for industry-typical September model year transitions in this timeframe.

Positions 15-17: Unknown

The trailing digits of the order number are followed by three seemingly-random numeric digits of unknown significance.

1991-present

Finally, a bit of order to lend method to the mayhem! Thomas Built Buses changed to a more straightforward and better-documented VIN format late in the 1991 model year.

1T79R4B26N1112325

Positions 1-3 and 11: Manufacturer and assembly plant

For reasons that elude me, Thomas' manufacturer prefix is contingent upon the configuration of the product:

Position 4: Model

Position 5: Body length

In 1991, Thomas' body model numbers changed from expressing the length in feet to expressing the length in body sections. As before, these body sections correlated with capacity. Note that the equipped capacity of a bus is almost always lower than the maximum capacity of the body, due to the need for open space around entrance and emergency doors.

Position 6: Type

Position 7: Engine

Position 8: Brake system

Position 9: Checksum

0-9 or X, calculated from the other digits.

Position 10: Model year

Thomas Built Buses retained a September model year cutoff through the first half of the 1990s. From that point on, the calendar started creeping further and further forward. MY1998 began by May of the year before; MY2000 began by February. By MY2005, the cutoff had migrated two calendar years in advance. And that's where things stand today, although Thomas' model year schedule remains a wee less exaggerated than corporate parent Freightliner's.

Positions 12-17: Production sequence

As before, the sequential number in the VIN correlates with the order number of the bus. Order numbers proceeded continuously from year to year (with a bit of overlap) and initially adhered to a five-digit length, resetting from 99999 to 00000 three times before being expanded to six digits in MY2017.

The VIN, however, has always contained a six-digit numeric serial...and Thomas has often played games with the leading digit, periodically skipping or backtracking as follows:

• At the start of this format in 1992, order numbers were in the 90000s and VINs were in the 090000 series.
• During MY1992, order numbers reset to 00000. VINs continued to 100000.
• During MY1999, VINs were switched from the 168000 series to the 068000 series with the last 5 digits remaining in sequence.
• Order numbers reset to 00000 again in MY2001, while VINs continued to 100000.
• When VINs racked up into the 168000 series again during MY2006, the numbering was switched over to the 268000 series with the last 5 digits again remaining in sequence.
• Order numbers reset from 99999 to 00000 in MY2008, and VINs reset from 299999 to 100000.
• VINs reached the 168000 series for a third time in MY2014. Predictably, this resulted in the numbering being switched over to the 268000 series yet again!
• Order numbers advanced from 99999 to 100000 in MY2017, breaking into six digits for the first time. This resulted in VINs resetting from 299999 to 100000 to maintain equality. The sequence has continued uninterrupted since, with order numbers and VINs reaching 200000 by the 2023 model year.

This information applies to Thomas' Type D buses, and specifically those built on in-house chassis. Thomas' newer Type C buses are built on Freightliner chassis, and continue to use the Freightliner VIN format.

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©2021-23 Andrew Turnbull.