I think it's safe to say that there is no mistaking these monster cars for anything else. The available popup images (in the table of releases) are just about actual size in order to get them to fit!

The prototype was developed by General American Transportation-- GATX-- built in September, 1965. It was listed in the Official Railway Equipment Register from January 1967 to January 1972, even though it was retired and donated to the Museum of Transportation in St. Louis, Missouri in 1971. While it was more or less a "proof of concept" car, a Federal regulation ended the production of "Rail Whales" like this by capping the capacity of tank cars at 34,500 gallons. This car held over 60,000 gallons! The GATX release of this quartet is relatively prototypical but the other three schemes, all for oil companies, are pure fantasy. That has not stopped collectors, as we'll note in a moment.

Built by Roco for Atlas, it is the only car Atlas ever had that requires four trucks. To make it work, there's an unusual arrangement: a bolster and end platform is attached to the body, and the trucks are attached to the bolster. Believe it or not, it will negotiate a 7 1/2 inch radius. But it ain't pretty. The trucks with the couplers are significantly longer than the "extended" trucks used on the hi-cube box cars, "Pig Palace" stock cars and auto racks. In fact, they are not used anywhere else. It's one reason why these cars are sought after-- if they're intact. Folks who buy the bodies only with the intent of just finding any old wheelsets to put under them are soon made aware of what a challenge they've taken on!

These cars were first introduced in 1970. They were reviewed in the "Trade Topics" column of the September 1970 issue of Model Railroader. By my reckoning are the last of the "First Generation", and have not ever been released since by any marketer. They are also easily the rarest of the whole bunch, especially in "as manufactured" or better condition. While oil company paraphenalia collectors ratcheted up prices past the $100 (!) range for mint in box examples in the late 1990's, prices realized since that spike have settled back somewhat. Even so, you may need to be prepared for some spirited bidding if you seek to add these four to your A1G accumulation.

Key spotting features for this car are:
- very large "frameless tank" with rounded ends and "whale belly" center
- platform bolster with two trucks at each end, as described above
- large single piece rectangular roofwalk assembly attached to top of car
- end platforms, one with attached brake wheel, an integral part of the truck/bolster assembly
- original long extended trucks (two) and trucks without couplers (two) with wheels pressed on separate axles
- Rapido couplers
Note that there is no "Atlas" identification visible on the car.

Note: The following information on conditions and "Approximate Value" prices are intended to be a guideline only and is presented with no warranties, express or implied. Caution: Definitions and prices can and do vary with collectors, buyers and sellers, and, of course, whether a person is buying or selling an item. That's the way a "free market" works...

A 3110 series tank car in "as manufactured" or "AM" condition has:
- bolster/end platform intact and not bent or broken
- original trucks in place with no damage
- roofwalk intact with no damage
- brake wheel present
- no weathering
- no abrasions, scratches or other damage to the paint
- "Rapido" type couplers, truck mounted (this is a case where changing to Micro-Trains® trucks and/or couplers is not a plus!).
Note that minor paint flaws on these cars were common and should not be considered especially "collectible"; in fact, I'd rather have a "perfect" paint job.

A 3110 series car in "mint in box" or "MIB," meets all "As Manufactured" criteria plus:
- no dust, dirt or wear on the car itself
- no wear on wheels (although discolored wheels are common)
- kept in the original large Atlas box
- box itself is intact with no cracks, breakage or crazing, with original Atlas label (usually white with black printing), plastic liner (usually blue), and cover. Both inserts and labels vary as the A1G series was sold for years. Store price stickers may or may not detract depending on the placement, size and wear.

"Runner" 3110 series cars are worth approximately 50-60% of the "As Manufactured" value but should be complete-- it's a must with these cars because the bolsters and extra long extended trucks are not available as spares from any other N Scale cars.

Table of Releases: Where available, click on "Image" to popup an image of the actual car.
Approximate Values Updated July, 2024.

Catalog #	Popup Image	Reporting Marks	Description	AV AM	AV MIB
3111	Image	GATX 96501	White and Blue, White Lettering, Large "Citgo" Logo R of Center	50-60	60-100
3112	Image	GATX 96502	White and Green, White Lettering, Large "Texaco" Logo Center	50-60	60-100
3113	Image	GATX 96503	White, Black Lettering, Blue "Wanda Petroleum" Center	50-60	60-100
3114	Image	GATX 96500	White and Red, Black Lettering, 1970's "GATX" Logo R	50-60	60-100

AV = Approximate Value (US$ range)
AM = As Manufactured (see above)
MIB = Mint In Box (see above)
Abbreviations: Hld=Herald, R/N=Roadname, L/R=Left/Right Side of Car