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kshansen

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And one that can confuse some is Cat would call the second version of a machine a "B" but never called on as an "A" Such as 966, 966B, 966C, 966D!
 

CM1995

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Welcome to the Forums John M!

Since the question was about a 977 I moved this thread over to the track loader forum.
 

kshansen

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actually the first 966 is a 966A.
Bob
Did Cat officially call it a 966A? If so that is one I never ran across. We had some of the first 988's and those never had a letter designation to them.

Well I guess I'm wrong did some digging and found this list of 966's on SIS 2.0!
966 Models.JPG
 
Last edited:

Welder Dave

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931 never had an A model but had B and C and C series II models. Not sure if scrapers had A models.
 

kshansen

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Guess Cat never figured out how to name things, or else never expected to be around so long with so many models and updates. Recall when they more or less ran out of part numbers and had to change from the number/letter/four number system to the three number-four number format. Not sure if that is the latest either!
 

Cat977

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I have some confusing stuff with the change from 977K to 977L. Any more light on the subject welcome!

I find this statement to be true. Caterpillar replaced 977K with 977L in 1971, but retained the 977K serial number prefixes. The 977L features increased horsepower to 190 hp when they went with the 3306 engine, beginning with 70J01303, 48J00586, and 11K03919
Also I find this statement production of 70J, 48J, and 11K ended in 1978; they were replaced by new 977L units.
 

Flat Thunder Channel

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I can't add any useful information to the thread. I would like to say the 977 is a pretty beefy machine! I watch a few YouTube creators who have these units / recused then from the weeds. Its interesting to learn a little more about the model designations. Thanks for sharing.
 
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