Dieselsite NCF plenum inserts reinforce the stamped-steel intake plenums on a 1999.5–2003 7.3 Powerstroke so the boots seal and the tubes do not crush when the clamps are tightened.

Factory plenums are thin. A tight boot clamp, especially with a stiff silicone boot, ovalizes the opening. That leaks boost and eventually ruins the plenum. These sleeves push in from the boot end and lock on the inward lip of the tube. The set is two inserts, one for each side, sized for the 3-inch plenums used on 1999.5–2003 trucks.

Install them while the valley boots are off. If a plenum is already bent, straighten the lip so the bevel can catch. Measure the opening before you order. Early 1994–1999 plenums are 2 inches and will not take this set. A year-swapped turbo or intake can also change the size.

Fitment

• 1999.5–2003 Ford 7.3L Powerstroke
• 3-inch plenums only
• Set of 2
• Push-in, no fabrication

Use them with a new boot and clamp kit. The inserts keep the tube round. The boots hold the boost.