Chuleton is a large steak or T-bone, depending on the cut. I wouldn't use the literal translation "old cow" unless it was supposed to be amusing, as it might cause offence. The general term for meat from cattle is beef, regardless of whether the animal was male or female.

New menu and dry aged beef steaks - - Bistecca Bistro
New menu and dry aged beef steaks. October 3, 2017. Recently to our flagship dish, which is Tuscan Bistecca, 1 kg of T-bone beef steak, we have added new ..

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Note added at 2 hrs (2020-01-23 17:51:51 GMT)
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Although Sarah is right when she says aged beef usually refers to cuts of meat aged post-slaughter, I'm using "aged" as a euphemism, because "old"doesn't strike me as appetising. When translating menus, my usual main criterion is to make things sound attractive to the diner. In my opinion "aged beef steaks" sounds better, and that's why I would use it. I stand by my suggestion.

This avoids the term "cow," especially as the meet may be from a male animal.

The New Trend in Steak: Old Beef - WSJ
Aug 5, 2019 - Dubbed “vaca vieja”—Spanish for “old cow”—it's a ribeye steak the menu described as being “8 years at harvest.” That's about four times older ...

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How To Properly Handle Beef - A Chef's Complete Guide
Jan 19, 2017 - Beef is considered a 'red' meat, meaning it has significant amounts of ... after they have bred for a few years, and are considered Old Beef.

Once a cow or bull is harvested, there are many steps involved in transforming it into the neat little packages of beef you buy at the store. First off, there are two types of beef you need to know about. That is Young Beef, and Old, or Heavy Beef. Young Beef is what is used for the best steaks and other upper-end cuts. Young beef has more marbling, is more tender and more delicately-flavored than a full-grown animal. The majority of animals are slaughtered young, around 18 months old, or when they reach 1200-1500 pounds in weight. These constitute the bulk of Prime, Choice, and Select Grades of beef. Older animals can be slaughtered after they have bred for a few years, and are considered Old Beef. These usually end up as Standard Grade. One other category is veal production, in which unweaned calves are purposely made anemic. They are slaughtered at around 8 months of age, or around the time when they would normally be weaned.

Old beef can be tougher, stronger-flavored, and heavier in texture, but still perfectly fine to eat. In fact, there are those that prefer Heavy Beef, especially for smoking and BBQing.

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Note added at 8 hrs (2020-01-23 23:54:05 GMT)
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so "heavy beef" would also work, though not so clear.