GMT400 (1988–1998) – OBS Discussions

Suspension, Wheels & Tires Lift kits, lowering setups, steering upgrades, and suspension builds for GMT400 OBS trucks and SUVs. Technical & Maintenance Diagnostics, repairs, maintenance procedures, common failures, torque specs, and factory-service technical discussion for GMT400 OBS trucks. Interior Interior repairs and upgrades for 1988–1998 GMT400 OBS trucks including seats, dash repair, gauge clusters, HVAC fixes, consoles, lighting upgrades, and restoration. Exterior Body, trim, bumpers, rust repair, paint, and exterior lighting upgrades for 1988–1998 GMT400 OBS trucks. Stereo, Wiring & Electronics Audio installs, wiring repair, gauges, and electrical troubleshooting for GMT400 trucks. Performance, Mods & Tuning Engine upgrades, bolt-ons, LS swaps, drivetrain mods, and tuning discussion for GMT400 OBS platforms.

Topic	Replies	Views	Activity
About the GMT400 (1988–1998) – OBS Discussions category GMT400 (1988–1998) – OBS Discussions	0	12	February 10, 2026
2000 K2500 Chevy CC Dash Question Interior	4	56	July 29, 2026
96–98 Vortec 5.7 guys: what's your key-on fuel pressure? Post your no-start story GMT400 (1988–1998) – OBS Discussions	0	27	July 23, 2026
OBS Headlight Knob Swap Using Chevy Express and GMC Savana Knobs Interior express-van , savana , obs , gmt400-obs , interior , headlight-knob , dash	0	78	July 5, 2026
'96-'98 OBS Interior LED Upgrade Interior obs , gmt400-obs , obs-interior , obs-interior-led , gmt400-led	1	249	May 27, 2026
OBS GMT400 Lighting TechPack (1988–1998) Technical & Maintenance gmt400-obs	1	74	May 26, 2026
OBS Headlight Conversion Guide – Sealed Beam to Composite (GMT400) Technical & Maintenance	1	44	May 26, 2026
OBS / GMT400 4-Hi Headlight Mod — Wiring Methods, Results and Troubleshooting Technical & Maintenance electrical , gmt400-obs , headlights , wiring , lighting-upgrade	0	42	May 26, 2026
GMT400 VIN Decoder and RPO Code Guide (1988–1998 OBS Trucks) Technical & Maintenance	0	44	April 20, 2026
Show Off Your OBS! GMT400 Photo Thread Exterior obs , gmt400 , gmt400-obs	0	33	April 14, 2026
Front End Rebuild: GMT400 Ball Joints, Tie Rods & CV Axles Suspension, Wheels & Tires	0	35	April 14, 2026
TBI to Vortec Swap Guide for GMT400 Trucks Performance, Mods & Tuning	0	72	April 14, 2026
GMT400 / OBS Common Problems & Known Fixes Master List Technical & Maintenance	0	73	April 14, 2026
Best Speakers for GMT400 Sierra – Front & Rear Upgrade Stereo, Wiring & Electronics upgrade , sierra , audio , stereo , gmt400 , gmt400-obs	0	41	April 12, 2026
GMT400 Stereo Upgrade – Single vs Double DIN Options Stereo, Wiring & Electronics	0	107	April 12, 2026
Best Head Unit for GMT400 Silverado – Fit Guide Stereo, Wiring & Electronics	0	46	April 12, 2026
Best Dash Cover for GMT400 – Crack Fix Options Interior	0	22	April 12, 2026
GMT400 Interior Door Panel Replacement – DIY Guide Interior obs-interior , interior , obs , gmt400 , gmt400-obs , guide , how-to	0	55	April 12, 2026
Best Seat Covers for GMT400 Silverado – Fit Guide Interior	0	22	April 12, 2026
Best All Terrain Tires for GMT400 2500HD – Ranked Suspension, Wheels & Tires	0	23	April 12, 2026
Biggest Tires on Stock GMT400 1500 – No Lift Suspension, Wheels & Tires suspension , obs , gmt400 , gmt400-obs	0	44	April 12, 2026
GMT400 Dash Cluster Repair – Speedometer & Gauges Technical & Maintenance	0	70	April 12, 2026
P0300 Misfire on 5.7 Vortec GMT400 – Common Causes Technical & Maintenance	0	30	April 12, 2026
GMT400 Distributor Failure Symptoms – How to Tell Technical & Maintenance	0	35	April 12, 2026
Leveling a GMT400 – What Are Your Options? Suspension, Wheels & Tires	0	27	April 12, 2026
GMT400 Front End Rebuild – All the Parts You'll Need Suspension, Wheels & Tires suspension , front-end , how-to , obs , gmt400 , gmt400-obs	0	59	April 12, 2026
Best Lift Kit for GMT400 1500 – 4 Inch No Rubbing Suspension, Wheels & Tires	0	24	April 12, 2026
GMT400 Frame Rust – Where to Look First Exterior how-to , obs , gmt400 , gmt400-obs	0	28	April 12, 2026
Rocker Panel Replacement on GMT400 – Step by Step Exterior	0	36	April 12, 2026
GMT400 Cab Corner Rust – Patch or Full Replace? Exterior	0	20	April 12, 2026