GMT800 (1999–2006) – NBS Discussions

Exterior Body panels, grilles, trim, bumpers, paint, rust repair, and exterior lighting upgrades for 1999–2006 GMT800 NBS trucks and SUVs. Performance, Mods & Tuning Engine upgrades, bolt-ons, LS performance mods, headers, drivetrain upgrades, and PCM tuning discussion for GMT800 NBS trucks. Technical & Maintenance Diagnostics, repairs, maintenance procedures, common failures, torque specs, and factory-service technical discussion for 1999–2006 GMT800 NBS trucks and SUVs. Interior Interior repairs and upgrades for 1999–2006 GMT800 NBS Silverado, Sierra, Tahoe, Yukon, Avalanche, and Escalade, including Cat Eye models — seats, dash issues, gauge clusters, HVAC fixes, consoles, and interior lighting. Suspension, Wheels & Tires Lift kits, leveling kits, lowering setups, steering upgrades, and suspension builds for GMT800 NBS platforms. Stereo, Wiring & Electronics Head units, speaker installs, amplifier setups, wiring repair, gauges, remote start, and electrical troubleshooting for GMT800 NBS platforms.

Topic	Replies	Views	Activity
About the GMT800 (1999–2006) – NBS Discussions category GMT800 (1999–2006) – NBS Discussions	0	5	February 10, 2026
2004 Tahoe warm front driver and passenger but still cool in back Interior	3	6	September 4, 2026
GMT800 Instrument Cluster Repair – Common Failures Technical & Maintenance gmt800-nbs , gmt800 , electrical , how-to , dash	12	117	September 3, 2026
Which GMT800 engine did you end up with — 4.8, 5.3, 6.0, or 8.1? Technical & Maintenance	2	14	August 25, 2026
Fuel Pump Replacement on GMT800 Trucks: Step-by-Step Technical & Maintenance	2	38	August 24, 2026
Pump rub check: who's opened their NP246 — and what did you find? GMT800 (1999–2006) – NBS Discussions	0	10	July 25, 2026
Fuel gauge lying to you? Sender or cluster — what did yours turn out to be? GMT800 (1999–2006) – NBS Discussions	0	2	July 25, 2026
Clicking in the dash — which blend door actuator was it, and how bad was the job? GMT800 (1999–2006) – NBS Discussions	0	16	July 23, 2026
Blower only works on high? Post your resistor and melted connector photos GMT800 (1999–2006) – NBS Discussions	0	9	July 21, 2026
2003–2006 owners: speedo stuck at 120? Post what fixed your cluster GMT800 (1999–2006) – NBS Discussions	0	8	July 21, 2026
8.1 Vortec L18 DBW Pinouts: 2001–02 vs. 2003–06 Harness Guide Stereo, Wiring & Electronics	0	13	July 12, 2026
GMT800 owners: what year would you buy today, and what would you avoid? Stereo, Wiring & Electronics sierra , silverado , gmt800 , buyers-guide	0	14	June 30, 2026
Don't Install Aftermarket GMT800 Headlights Until You Do This Stereo, Wiring & Electronics sierra , silverado , gmt800 , how-to , headlights , diy , avalanche	0	29	June 24, 2026
8.1L Vortec Spark Plugs: ACDelco 41-983 at .045" Gap — and What to Do When You Break Your Wires Technical & Maintenance 8-1-vortec , maintenance , gmt800 , spark-plugs	0	23	June 23, 2026
8.1L Vortec Startup Chatter Fixed: Ditched the 5W-30, Switched to Rotella T4 15W-40 Stereo, Wiring & Electronics avalanche-2500 , 8-1-vortec , maintenance , gmt800	0	13	June 23, 2026
99-02 GMT800 Double DIN Installation Guide – The Right Way to Do It Stereo, Wiring & Electronics 99-02 , audio , guide , gmt800-nbs , stereo , gmt800 , how-to	1	236	June 12, 2026
GMT800 4.8 / 5.3 / 6.0 Hot Idle Low Oil Pressure — Post Your Readings and Fixes Technical & Maintenance gmt800 , oil-pressure , engine , diagnostics	0	20	May 25, 2026
GMT800 Leveling Kit vs 6 Inch Lift – Ride Quality Comparison Suspension, Wheels & Tires	0	26	April 20, 2026
GMT800 Transfer Case Pump Rub Fix – NP246 Repair Guide Technical & Maintenance	0	11	April 20, 2026
4L60E Common Failures and What to Fix First (GMT800 Guide) Technical & Maintenance	0	33	April 20, 2026
5.3 vs 6.0 Engine Differences – LM7 vs LQ4 (GMT800 Guide) Technical & Maintenance	0	37	April 20, 2026
GMT800 Towing Capacity Chart – 1500, 2500, and 3500 (1999–2006) Technical & Maintenance	0	46	April 20, 2026
GMT800 Tailgate Rebuild Guide – Cables, Hinges & Latches (Video + Parts) Technical & Maintenance	0	23	April 20, 2026
Show Off Your NBS Build! GMT800 Photo Thread Exterior	0	15	April 14, 2026
Front End Rebuild: GMT800 Ball Joints, Tie Rods & CV Axles Suspension, Wheels & Tires	0	47	April 14, 2026
4L60E & 4L80E Transmission: Common Failures, Symptoms & Fix Guide Technical & Maintenance	0	23	April 14, 2026
Best Amp for GMT800 Silverado – Power & Install Guide Stereo, Wiring & Electronics	0	23	April 12, 2026
GMT800 Subwoofer Box Build – Under Seat vs Custom Box Stereo, Wiring & Electronics audio , stereo , gmt800-nbs , gmt800 , how-to	0	43	April 12, 2026
Best Head Unit for GMT800 Silverado – Top Double DIN Picks Stereo, Wiring & Electronics	0	78	April 12, 2026
Best Floor Mats for GMT800 Sierra – Custom vs WeatherTech Interior	0	30	April 12, 2026