When I first start my blazer and take off in first gear there is usually a loud blowing sound that gets quieter when the trans shifts into second gear.

This only lasts for about the first minute of driving the vehicle and then everything runs quiet.

Any idea what this could be?

 

is it just when it is cold. if so, that is normal. that is just the fan clutch.

 

^^^^ +1
Its normal.

 

When the engine is cold perhaps; however, it also happens during the summer time. Does this still sound normal?

 

if it's hot enough it may do it past 1st gear. Pop the hood and see if you can turn your fan freely, you should be able too.

 

that fan clutch can get really annoying.

 

Yeah it really can! LOL

 

WA WA WAAA WHAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA

every time i start up in the morning. someday il switch over to a e fan.

 

go electric

 

Normal fan clutch operation, Winter or Summer. The severe duty clutch takes longer to disengage when cold and engages at a lower temp when the radiator starts to overheat. If it stays engaged, it's broke. If it won't engage, it's broke. The standard duty clutch will shut up quicker on start ups BUT, it will allow radiator temp to increase higher before it engages. Don't like the noise? Get an electric fan, but be aware, they're quieter because they don't move as much air to cool the radiator. Think of the fan as a thermostat for the radiator, not the engine, it has its own thermostat.