The GMT800 (1999–2006) uses an independent front suspension with upper control arms, lower control arms, ball joints, inner and outer tie rods, and (on 4WD) CV axles. It’s one of the better-handling front ends GM built for this era, but it does wear — especially on high-mileage trucks.
Common Front End Symptoms
- Clunking over bumps — Upper or lower ball joints, sway bar end links
- Wandering steering / loose feel — Worn tie rod ends or inner tie rods
- Shudder or death wobble at speed — Multiple worn components together
- Uneven tire wear — Alignment out, often due to worn front end parts
- Clicking or popping turns (4WD) — CV axle worn or damaged
GMT800 4WD Front Suspension Parts
A complete front end rebuild includes:
- Upper control arms with ball joints (upper BJs are not serviceable on GMT800 — replace the full arm)
- Lower ball joints (press-fit; can be replaced separately)
- Inner tie rod ends (x2)
- Outer tie rod ends (x2)
- Sway bar end links (x2)
- CV axles if clicking or binding (4WD only)
A kit like the 13pc 4WD Front Suspension Kit for Silverado/Sierra 1999–2006 covers control arms, ball joints, and tie rods in one go — saves on individual part pricing.
Upper Control Arms — GMT800 Specific
Unlike older trucks, the GMT800 upper ball joint is integrated into the upper control arm — you cannot replace just the ball joint. If the upper BJ has play, replace the full UCA.
Check for play by:
- Lift the front axle under the lower control arm
- Grasp the tire at 12 and 6 o’clock
- Push/pull — any movement at the upper joint = replace the arm
CV Axle Inspection (4WD)
A failing CV axle will click or clunk during turns (inner CV) or acceleration (outer CV). Test by turning to full lock and accelerating slowly — a clicking sound = failing outer CV joint.
Inspect the CV boots for cracks or grease slinging. A torn boot leads to rapid joint wear from contamination.
Alignment Specs (GMT800 1500)
| Parameter | Spec |
|---|---|
| Front Camber | 0° to -0.5° |
| Caster | 3.0° to 5.0° |
| Toe (total) | 0.04" to 0.16" in |
Always align after front end work. The GMT800 has adjustable camber via eccentric bolts on the lower control arm.