what is this part?

[scasey28]

Ok this is really buggen the sh$t out of me. I was under my blazer the other day and noticed a dial that says increase and decrease. Its a twist dial that is located below the fuel filter. Does anyone know what this could be. The pixs dont really show it to well, however its right below the fuel filter. Thanks

 

[bigblock72]

Looks like an adjustable proportioning valve for the rear brakes.
Should be plumbed into the rear brake line. Hopefully they gutted or removed the stock proportioning valve.

 

[scasey28]

Your right, that what it is. Im going to look into it and see just what it does. Thanks alot.