Hard brakes -- on 1976 airstream.

The brake booster will be under the driver's floor, best way to see it will be under looking up.

Not knowing what basic service is a couple of guesses. If someone pulled the wheels and looked at the pads and they looked good they could still be glazed and not stop well. Shoes on the rear could be the same.

The calipers have a lot of sliding machined surfaces that need to be clean, smooth, and well lubed so they move freely. Same for the drums, the adjusters need to be free, lots of other pieces that rust including the backing plate.

Thanks folks! Tomorrow I'll try to locate the brake booster, check for leaks and change the fluid. Fingers are crossed.

I know it sounds strange but change the power steering fluid before you go further.

I thought it was a silly suggestion but GM are tied into it.

I did it any was surprised at the pedal difference.

Very easy to do.

Most likely the brakes have a hydroboost which runs off the power steering pump. a quick google search brings up this, which looks about right. http://www.freeasestudyguides.com/hydroboost-brake-assist.html

One thing to keep in mind is there are several different grades of brake pads available for most vehicles. Some have a much greater coefficient of friction than others do. I've seen very significant differences from buying cheap pads, compared to buying premium pads.

Yes. This is a GM chassis. Thank you!

along with the brake booster, which is a quick check to see, If the brakes have been over heated then you will have to really press for them to work.

Sounds like the power brake booster. Is this on the GM chassis?