Buy OEM 1999 Cadillac Part # 15854941. Engine Mount (Front, Rear). 1/2 ton, 5.3, 6.0 liter. 2WD. 2WD, 5.3 & 6.2 liter. 4.8, 5.3, 6.0 & 6.2 LITER, 6.2 liter. Avalanche; 5.3L

Mount.
A part that locates and supports the engine. It also reduces vibrations from the engine. Assembly - ENGINE. Motor. Side.

Engine Mount

1/2 ton, 5.3, 6.0 liter. 2WD. 2WD, 5.3 & 6.2 liter. 4.8, 5.3, 6.0 & 6.2 LITER, 6.2 liter. Avalanche; 5.3L. Avalanche; 6.0L. Escalade ESV. Silverado, Sierra Hybrid. Silverado, Sierra; 5.3L; w/o Flex Fuel; 4WD. Silverado, Sierra; 6.0L; 2WD. Silverado, Sierra; 6.0L; 4WD. Silverado, Sierra; 6.2L; 2WD. Tahoe, Yukon, Escalade. Tahoe, Yukon, Escalade; 5.3L, 6.2L; 2WD. Yukon XL, Suburban; 5.3L, 6.2L.
Engine Mount - Repair or Replace
A broken or worn engine mount will often cause your 1999 Cadillac to lurch when shifting gears, and you may also hear a clunk when accelerating or braking. Another likely symptom is excessive vibration from your engine.