2004 SCREW. I had the truck in for another reason, but asked if they would remove the bug sheild too.

Well the broke the sheild in the process and now starting from speeds as low as 50 mph I'm getting a whistling noise. Sounds like I have a .22 shell mounted to the hood. I took it back, mech didn't hear anything, I got up to speed, "ooo that whistling noise". They jacked around with the little rubber stoppers that support the hood and it changed nothing.

Any suggestions?

 

There are 2 hood seals used to prevent noise and control air circulation: one in the front (attached to the hood inner panel) that seals off against the radiator support and one along the back that seals to the leafscreen/cowl. By adjusting the hood bump stops, they were trying to get the front seal to have better contact to the radiator support...they may have been unsuccessful. When hoods are designed, there is typically a 10mm clearance between the hood and the lamp. This allows for overslam or overbending of the hood in front of the bump stops so the hood doesn't crash into the headlamps (very expensive to replace a headlamp housing). My guess is when they put on the bug shield, they had to raise the hood bump stops to prevent the bug shield from crashing into the headlamp (Hood to lamp clearance was 10mm, added 3 mm thick bug shield, had to adjust hood up 3mm to get the bug shield away from the lamp).

To see where the front seal is contacting the rad support, you may be able to see "clean" marks on the rad support or you could put some white chalk dust on the rad support and close the hood. Open it and you should see where the seal is contacting.

You could check to see the distance from the hood to the headlamp and adjust the bump stops down more to force the front seal to make better contact on the rad support. Like I said...BE CAREFUL, all it takes is one slam to crack a lamp. You can put a piece of clay or playdough on the headlamp and close the hood, open the hood then measure the thickness of the clay. You would NOT want to shim the seal down, as you would create an opening above the seal and could end up with the same problem.

As far as the rear seal is concerned, TSB 04-18-8 is for preventing hood flutter at highway speeds. Basically they insert a piece of rubber tubing inside of the rear seal bulb to make the seal stiffer. You didn't mention hood flutter but making the rear seal stiffer may offer a better seal.

Lastly, I have a whistling too...but I think it is coming from the mirrors. Haven't looked into it though...doesn't bother me too much.

 

Since you can reproduce the whistle it should not be difficult to locate the source. You can do this by stopping or reducing (stuffing orifices or taping off) the airflow one place at a time ( hood, grill, driving lamps, etc) until the whistle disappears. When you have located the source, it's a matter of dealing with the airflow. Luckily you have access to one of the world's greatest authorities on whistling.
Papa