1947–1972
Restoration, drivetrain, preservation.
Featured: Rust Repair
From the forum · Rust Repair
Rust Repair on Classic Chevy Trucks: Where to Start
Read the thread →Chevy · GMC · Cadillac full-size trucks & SUVs Find Your Truck.
Find Your Truck.
Fix It Right.
From Squarebody to T1XX, find generation-specific guides, known problems, real repairs, build discussions from full-size GM truck owners, and decode your truck’s option codes.
Jump to your generation Jump to your powertrain
1973–1987
1988–1998
1999–2006
2007–2013
2014–2018
2019–now
Engine Swaps • Wiring • Fitment
LB7–L5P : All GM Diesels Welcome
2019–now
Start with your generation
Find Your Truck
Every generation has its own hub — buying guides, the problems these trucks are actually known for, and fixes that hold up. Each card links to the hub, plus a real forum thread to jump straight into. Not sure exactly what you are working on? Decode the RPO codes off your glove box sticker and see how your truck left the factory.
1973–1987
Restos, swaps, brotherhood.
Featured: C/K ID Guide
From the forum · Buyer Guide
Squarebody C/K ID Guide: Years, Trims & Build Codes
Read the thread →1988–1998
The trucks that built the culture.
Featured: Interior LED Upgrade
From the forum · Interior Upgrade
OBS Interior LED Upgrade (1995–1998)
Read the thread →1999–2006
5.3 & 6.0, oil pressure, mods.
Featured: Cabin Air Retrofit
From the forum · Common Upgrade
GMT800 ’03–’06 Cabin Air Filter Retrofit
Read the thread →2007–2013
AFM, oil use, real-world builds.
Featured: Tailgate Assist
From the forum · How-To
GMT900 Tailgate Assist Install (2007–2013)
Read the thread →2014–2018
Modern truck tech & tuning.
Featured: Tailgate Assist
From the forum · How-To
K2XX Tailgate Assist Install (2014–2018)
Read the thread →2019–now
Latest Silverado & Sierra.
Featured: 10-Speed Shudder Fix
From the forum · Diagnostic
10-Speed Shudder on T1XX — How to Fix It
Read the thread →All platforms
The complete swap guide + checklist.
Featured: LS Swap Guide
From the forum · LS Swap
LS Swap into a Full-Size Chevy / GMC — Complete Guide
Read the thread →Start with your powertrain
Find Your Engine
Two engine paths get their own hub — the LS swap and the Duramax diesel. Engine choice, wiring, fitment, known problems, and the forum threads to jump into.
All platforms
The complete swap guide + checklist.
LB7–L5P
All GM diesels welcome — diagnostics, towing, Allison, DEF.
The primary reason to be here
Get Help From Owners Who’ve Done It
Post a question, document your build, share a repair, or help another GM truck owner. Registration is free.
- Ask generation-specific questions
- Document your truck or build
- Get practical help from real owners
- Preserve solutions for the next owner
From The Forum
Newest
GMT900 Active
GM 5.3L Oil Consumption Issues (2007–2013): What You Need to Know
K2XX Active
2018 Silverado AFM/DOD Delete
GMT800 New
2000 K2500 Chevy CC Dash Question
Most read
Common Repair
GMT800 Instrument Cluster Repair
Stepper motors, backlight bulbs and dead gauges — what to fix before you throw a whole cluster at it.
Common Repair · GMT800
Read the Thread →
Interior Upgrade
OBS Interior LED Upgrade
Convert the factory HVAC, cluster and interior lighting to LED on a 1995–1998 OBS, bulb sizes included.
Interior Upgrade · OBS / GMT400
Read the Thread →
Engine Diagnostic
5.3L Oil Consumption: What to Check
Why AFM 5.3 engines burn oil, how to confirm it, and the fixes owners actually use before a teardown.
Engine · GMT900 / AFM 5.3
Read the Thread →
Transmission
10-Speed Shudder on T1XX
The torque-converter shudder on the 10-speed, how to tell it apart from driveline vibration, and the fix.
Transmission · T1XX
Read the Thread →
LS Swap
LS Swap into a Full-Size Chevy / GMC
The updated overview of swapping an LS into a full-size GM truck — mounts, wiring, cooling and drivetrain.
LS Swap · All Platforms
Read the Thread →
Buyer Guide
Squarebody C/K ID Guide
Decode years, trims and build codes on 1973–1987 C/K trucks before you buy or start a project.
Buyer Guide · Squarebody
Read the Thread →
Backed by real trucks 
Guides and Real Builds
Technical information from FSC, backed by trucks and repairs documented in the community.
Featured Technical Guides
Engine
5.3 Oil Consumption: Why It Burns Oil & How to Fix It
Known Problem · GMT900 / AFM 5.3
Common Repair
Blend Door Actuator: Clicking Dash Fix & Relearn
HVAC · GMT800 / GMT900
Electrical
How to Find a Parasitic Battery Draw
Diagnostic · GMT400 – K2XX
LS Swap
The Complete LS Swap Checklist
Powertrain · All platforms
From Members’ Garages
2002 Avalanche 2500 8.1L
An 8.1 Vortec / 4L80E tow rig — lift, wheels, cluster upgrade, double DIN and a bed drawer build.
Build thread · GMT800
The FSC Yukon Project (FSC1)
The community-build 1997 OBS Yukon: mechanical refresh, interior LEDs and an Escalade console swap.
Community build · OBS / GMT400
Show Us Your Truck
Post your full-size GM truck or SUV, tag your generation, and add yours to the member gallery.
Community thread · Add yours
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Current FSC projects
The 1997 GMC Yukon Project
Follow the mechanical refresh, interior work, lighting, exhaust and other updates made to FullSizeChevy’s 1997 OBS Yukon. The project was formerly connected to the cancelled FSC1 promotion. The Yukon is no longer a giveaway vehicle.
- Full mechanical inspection and refresh completed
- Interior LEDs, seat recovery and OBS Escalade console swap done
- New headlights, billet grille, exhaust and detailing done
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