On the plus side.... the transmission is fairly standard. Same one is used is many GM trucks and SUV's. I'm not sure how common Chevy and GMC is down there though but I'd imaging there are a lot more of those than H2's. Even saying that though, there are a lot of variations of the 4L60 transmissions. 4WD and 2WD are different lengths being the primary difference and then there are slight variations which from what I understand are slightly heavier duty like the 4L65, 4L70, and 4L80. I think the 4L80 is electronically different though. From what I've read the H2's have the 4L65 but I'm not 100% sure on that. Here in the US you can get one rebuilt for as little as $500 but generally a quality rebuild with warranty and installation is closer to $2500 with the labor and all.

 

 

 

Excellent!

 

Go get it . You only live once. Solo se vive una vez
Now to the point . First get rid of those wheels. I'm sure in Panama those are expensive. You may save that money to fix any problem like the transmission .
those wheels not only looks bad but also will affect the front end, steering and also the rear suspension

perform a compress test and a vacuum test
check transmission for coolant in the fluid
(make sure to check the transmission aftermarket coolant mod)
in the worse scenario you are looking at a rebuilt transmission around $2000 and a few parts to fix this and that another $2000
this are Gm parts which are generally inexpensive at least in the us . Any Gm mechanic will know exactly how to fix anything on this rigs . No need to be a hummer expert
also helps if you have some mechanic skills and some tools to fix little things which for sure are going to show up in a 175k vehicle