Expert GMC Envoy transmission service in Chicago. Free computer diagnostic, 2-year / 24,000-mile warranty on rebuilds, all years.
We will contact you as soon as a service member is available by call, text, or email.
2002 - 2009: 4-speed automatic (4L60-E) on I6 and V8 models. 2002 - 2009: 4L80-E on Envoy XUV and heavy-duty trims (V8). 4WD: NV226 or NV246 transfer case on 4WD variants. Envoy XL shared same drivetrain as standard Envoy.
The Envoy was discontinued after 2009 but remains common in Chicago. The 4L60-E is one of GM's most frequently rebuilt transmissions - we've done hundreds. The sun shell failure is when-not-if on V8 models beyond 120k miles. We use upgraded hardened sun shells in all 4L60-E rebuilds. Transfer case encoder motor failures are often electrical rather than mechanical.
4L60-E and 4L80-E use Dexron VI. Transfer case: AutoTrak II for NV246.
Verify exact spec on the dipstick label or owner's manual before fill. Recommended change interval: every 60,000 miles for normal driving, 30,000 miles under severe service (towing, stop-and-go, hot climates). Pan service typically takes 6 - 8 quarts; a full fluid exchange takes 10 - 14 quarts depending on cooler-line capacity.
4L60-E rebuild: 3 - 4 days. 4L80-E rebuild: 3 - 4 days. Transfer case encoder motor: 1 day.
Every vehicle needs diagnosis before anyone can promise a repair path. These are the situations we help organize before you decide what to do next.
Tell us when it happens, whether reverse still works, and if warning lights are on. A scan and fluid check come before guessing at a rebuild.
Fluid condition, leak location, and driving distance matter. If the vehicle is slipping badly or overheating, towing may be the safer next step.
A failed solenoid, valve body, converter, or internal clutch problem can lead to very different repair paths. The goal is a clear diagnosis and written estimate.
4L60-E sun shell failure - very common on Envoy V8. Full rebuild required: $1,500 - 2,100. The good news: it's a job we do all the time and we use upgraded sun shells.
No - that's the transfer case encoder motor. Often an electrical fault rather than mechanical failure. Encoder motor replacement: $350 - 550.
If the rest of the truck is in good shape, yes. The 4L60-E rebuild with upgraded parts runs $1,500 - 2,100 and gets a 2-year / 24,000-mile warranty. The Envoy's body and engine are tough - the transmission is the weak link.
Every 30,000 miles on any Envoy over 100k miles. Fresh Dexron VI protects aging seals and solenoids.
Identical - Envoy and TrailBlazer share the same 4L60-E. Same rebuild, same pricing.
Same-day appointments available. Honest estimates, no surprises. We've been doing this since 1987.
