Hello,
I'll be flying domestic within Brazil, and am wondering if these connection times are possible. I'll be by myself with one carry-on bag only, and all flights will be on GOL.
Monday, April 30
Arrive CGH from GIG, 11:10AM
Depart CGH for CGR (Campo Grande), 11:45AM
(35 minutes!)
Friday, May 4
Arrive GRU from CGR, 9:30AM
Depart GRU for MAO (Manaos), 10:35AM
(65 minutes seems reasonable??)
Many thanks, in advance. Everyone's help is appreciated.

If there is no surprise like a strike or a protest or anything eunexplainable happens these days ... Yes, connections will be possible; even in 35 minutes since Congonhas is a small airport and all your flights are with the same company. Inform GOL about your connection flights, so they will arrange things for your convinience.

If you already have your tickets it is a moot point. You want to know whether to worry? Worry. Flights are often late even without a wildcat controllers strike. I have heard Congonhas is particularly bad for delays (a local news story listed it as the countrys airport that was most over-capacity). GRU is a huge airport but since you are switching from domestic to domestic flight on the same airline you may well be okay. Assuming no delays due to weather (Sao Paulo gets those regularly), personnel, etc.

p.s. I live in Brazil. The last time I flew Gol, Fortaleza to Recife, our flight was 3 hours late. Return flight was right on time. I would not personally bank on a 35-minute connection anywhere in Brazil. My wife (Brazilian) never wants less than a 2-hour connection when flying into Sao Paulo to catch an international flight.

Bubbak, the scenario you describe is about to get even worse, as Congonhas main runway will be shut on 14 May for repair works (they are about to finish work on the second runway). Lots of flights will be diverted to Guarulhos and Campinas, it's wise to check with your airline beforehand even if the word Congonhas is printed on your ticket.

Airports throughout Brazil were once again in chaos yesterday as Federal Police engaged in a one-day strike (or work slowdown). Waits of up to 3 hours for departing passengers to get through security checks were reported. The line at Congonhas stretched for 2 kilometers, one paper said. In Brazil, always be prepared for the worst and be pleasantly surprised if it doesn´t happen.

Thanks for the information. I bought the CGR-GRU-MAO flights, so keep your fingers crossed that the 65 mins enough...

Thanks for your responses.
I booked the 65 min connection (CGR->GRU->MAO) and made the MAO flight, but just by the skin of my teeth. Who knew you had to go through customs/immigration again when coming into Sao Paulo from Campo Grande??? I'm not sure if the plane was an international flight that just stopped to pick up a few more passengers in Campo Grande, or if that area is so close to the Bolivia/Paraguay border that Brazil decided to treat it as "international" for the sake of increased safety/control.
Anyway, thankfully the lines were short in GRU, and the GOL personnel were very helpful about getting me on the flight in time. If either of those hadn't been the case, I would have missed it. By the way, checking in for GRU->MAO at the same time as the CGR->MAO flight was not possible.
Re: the 35 min connection, for future readers' reference, there would simply be no way to make that.