I just bought a 1994 Chevy Silverado. I have noticed a few new sounds. First, I have a rattling sound or a what sounds like changes rattling in a cup coming from the transmition box inside of the cab. Also, A new sound has come up, I drove it on a trip, about 80 miles on the highway, going about 75 MPH. When I stop I heard this gurgling sound, I really didn't think about it a first, now its everytime I slow down and come to a stop or when I put it in park I hear that noise.

If anyone has any ideas or suggestions I would greatly appreciate it.

Thanks

 

I'm not 100% sure for the 94 but...
GM trucks like yours have this problem for a while and this is caused by a strong flow of coolant inside your heater core. To eliminate this, there is a rubber restrictor in the inlet side of the heater hose installed in it. This restrictor or orifice might have broken and must be replaced. Make sure to check this and replace if necessary.

 

I had the same noise. Never had a problem. Eventually noticed coolant was always low at about the same level when I checked it. I found a hairline crack below the filler neck in the plastic. Replaced the radiator. No more sound. I would try and repair it first if i had to do it agin though. Good luck.