It's hard to give an accurate answer without knowing a lot more about the car. How many miles? What kind of condition is the car in other than the obvious engine problem?

We have a 2012 Traverse with about 62,000 miles on it and it's in very nice condition. Wife was recently offered $10k in trade on it for an Equinox but we just can't give up the Traverse. They're generally very well-regarded cars. So, sounds like they did pretty good at $17k depending on the trim and condition.

There's only one motor...GM's 3.6L V6. It's kinda like the 350...been around forever and generally a very good motor. A low-mileage engine can be had for a little over $1500 (plus labor to replace) so I'd definitely consider doing that unless the car is otherwise not worth it.