2003 GMC Envoy: complete transmission failure

Filed Jul 24, 2018 · Engine · 230,000 miles · GA

Gradual coolant loss over time and no evidence of leak. This was due to a crack in the cylinder head that gm admitted to knowing about in tsb 06-06-01-019b on june 12, 2007). Coolant was slowly leaking into the oil, but was unnoticeable until it started to affect oil pressure from the oil becoming slushy and ruining the engine. This ended up resulting in resulted in the low engine oil light suddenly coming on and the car to stop running on a highway. The engine started steaming and the car was overheating. Mechanic is now saying the engine is in an unoperable shape due to driving with continued low oil pressure (no light had appeared until day of incident). Gm had sent out a bulletin admitting to the issue but did nothing to notify their customers. They should immediately recall the affected vehicles and/or pay for a replacement. I had just put in a new transmission to my gmc envoy, expecting it to last for years.

Filed May 22, 2010 · Transmission · 95,000 miles · OH

The transmission failed in my 2003 gmc envoy with approx 95,000 miles. While driving down the road I went to pass a slow moving vehicle. As the transmission down shifted there was a "bang" so I pulled over to look under the truck, and made sure nothing had fallen off. I got back in the s.u.v. And made my way back home with no problem. The next day when I went to back out of my drive way there was no reverse. I called a local gm dealership and was told that the problem appears to the sunshell gear. According to multiple post online, seems to be a common failure among envoy's and trailblazer. I checked the fluid and it appears to be fine, not low, not burnt, and still red and clean.

Filed Aug 10, 2009 · Transmission · 72,456 miles · PA

First problem occurred in 2008, driving to work in 2003 gmc envoy slt (original owner) heard clunking noise when downshifting. Took car in to shop for repair (just over 50k miles so out of warranty). Shop explained that the transmission needed to be replaced $4000 with one year warranty. Since I was planning on driving cross country decided to do the repair. One year later, driving and trying to accelerate on a ramp to find SUV stuck in second gear and wouldn't accelerate while RPM kept going up. Also heard clunking when downshifting. Pulled over and tried to get gears to shift by slowing down and speeding up (to get RPM to drop). Drove car to dealer who stated I needed a new transmission (again). Dealer removed transmission and "found input bushing in pump bad. And reverse drum. And had heavy metal contamination". When asked why this is my third transmission in six years the service agent said "bad luck". Both replacement transmissions were rebuilds. The current transmission is not under warranty.

Filed Jul 31, 2009 · Transmission · 80,700 miles · CT

I have a 2003 gmc envoy, 80,700 miles original owner. While merging onto highway transmission locked in 2nd gear. Engine RPM's increased to 5,000 speed dropped to 20 MPH creating a dangerous situation with oncoming traffic. This happened without warning or any indication of a problem. I had vehicle towed to gmc dealer, asked if there were any known problems with gmc envoy transmissions and was told there were none. The diagnosis, my transmission exploded internally with a failure of the sun shell gear and torque converter. Transmission could not be rebuilt and the cost of installing a re manufactured transmission was $3700! Gm has been having these transmission failures since 2002 with no acknowledgment of liability!

Filed Nov 6, 2006 · Transmission · 82,000 miles · MI

The transmission failed in my 2003 gmc envoy with 82,000 miles. The problem appears to the sunshell gear which seems to be a common failure with this transmission. Because the transmission was downshifting hard, I took the car to a gmc dealer less than 1000 miles ago to have the transmission looked at. I was told my the dealer that there was a problem but not to worry about it. Now the transmission has no reverse and the repair estimate is $1,800.

Filed Aug 24, 2004 · Electrical, Transmission · NY

Upon starting the vehicle and taking off the gear shifted, and then dropped down to the correct gear it should have be in. Transmission was replaced within the first six months. Also, starter made a clicking noise several times before starting. Then the vehicle shut down.