2020 CHEVROLET SUBURBAN Engine Problems

12 complaints about Engine

12
Complaints
0
Crashes
1
Fires
0
Deaths

High Severity Issue

This component has been associated with crashes, fires, or deaths.

This Problem Across All Years

All Engine Complaints (12)

Nov 25, 2025

The contact owns a 2020 Chevrolet Suburban. The contact stated while driving 25 MPH and depressing the accelerator pedal, the vehicle started shuddering. The check engine warning light was illuminated. The vehicle was taken to an independent mechanic, where it was diagnosed and determined that the engine needed to be replaced. The vehicle was then taken to the dealer, where it was diagnosed and determined that the camshaft needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure, but no assistance was provided. The approximate failure mileage was 95,000.

Mileage: 95,000

Nov 7, 2025

Our engine went at 100,800 miles, costing us $15k in June 2025. Then our transmission went 3 months later, now costing us another $7k. GM is offering very little financial assistance. It's quite inconvenient that these major mechanical issues occur right after factory warranty. It is at a dealer getting fixed, again, but how can this be ok with GM to see their product be such a failure for consumers? Recall or not, this has left a horrible taste in our mouth for GM/Chevy vehicles. We will no longer trust the longevity of their vehicles and will educate others to be weary on purchasing vehicles. We can understand mechanical failures over time, but not to this extent, and we're very disappointed in the customer service and available assistance for someone that just spent nearly $23k on a vehicle that's less than 5 years old.

Aug 12, 2025

The vehicle is stuttering, intermittent, jumping, miss firing during acceleration, and hard down shifting. The check engine and forward collision unavailable light flashed as the vehicle struggled to accelerate. According to Chevrolet the camshaft and two lifter has failed.

Jun 29, 2025

Had to replace motor. Had to replace the vibrater in the seat. Had to replace transmission. Electric shorted

Jun 22, 2025

The vehicle has 70,000 miles. The engine has failed and been replaced two times. We are on the third engine. The first time was in 2021 the second time was in 2024. I heard that others are having a similar issue. This is a 2020 .6.2L RST. The engine failed the first time while driving at high speed the car just stopped working. The second time we heard it failing and were able to drive it to the dealer where the engine fell apart in the parking lot The vehicle has had other issues too. Currently the wire harness has failed. This has happened several times but the dealer has not figured out a repair. Each time it’s failed while driving causing power steering to fail while driving. I don’t not trust my teen drivers around the vehicle or to drive.

May 3, 2025

Complete engine failure. Entire engine needed to be replaced. Only 5 cylinders were working causing the vehicle to shake and shudder violently

Apr 30, 2025

Out of the blue, while driving, my car started lurching and making a weird rattling noise. I was able to make it to a mechanic, where I learned the cylinder lifters collapsed and crankshaft were broken. The mechanic told me this is a common defect for GM motors. My vehicle is only five years old, so to learn we have a $10-20,000 repair on our hands was paralyzing and devastating.

Mar 3, 2025

engine replacement at 120,000 miles. I was told by Mechanic that the 2020 Suburban's have a problem with the fuel injector wiring harness dry rotting and the sensor changing the engine from V8 to V6 when on highway going bad causing misfire in engine and ruining the engine.

Nov 6, 2024

On October 27, coming back from a family trip at 10 PM at night on a major highway, the suburban all of a sudden quit. Traveling at 70 miles per hour, all of a sudden, when pressing the gas pedal, the car would not accelerate and the RPM gauge was erratically moving. The car started to slow down till it eventually just quit and it would not go anymore. We were stranded in the middle of the highway with cars coming and going both ways. It was scary, it was dark, and dangerous. A tow truck was called and they told the suburban to a Chevrolet dealership 60 miles away. The following day, the dealership informed us that the transmission was not repairable and that they had found metal pieces in the transmission. They informed us that the only way to repair was to replace with a new transmission. They informed us that these transmissions are faulty and that it’s common for them to replace transmissions in suburbans about twice a month. We were not happy to find this out because this is the second transmission in a second Suburban that we have owned that we have had to spend $12,000 on between both vehicles. The car was out of warranty, Therefore, the expense was totally on us. I need help trying to see if I can get reimbursed for these expensive faulty transmissions that are not our fault! We have serviced car when due. There were 4 small children in the car and we could’ve had a tragic accident because car quit suddenly! Please help!

Sep 6, 2024 Fire

I put vehicle in Chevy dealership 7/8/24 for cold start knocking sound. Dealers called 2 days later said it was defective lifter issue on the 6.2 liter GM engine.Dealer ordered new engine.on 8/23/24 while test driving vehicle with new engine in it while driving on the highway a fire started under the engine. I was told by dealer that people were telling the driver the vehicle was on fire. He abandoned the vehicle on the highway as it burned up inside and outside. Fire trucks put the fire out.Vehicle is total loss. Waiting two weeks for GM to tell me what they will do to help me. No reply to phone calls or emails unless I call them to check and find out what is going on. I wrote email to GM CEO and no reply. Insurance for me offered me pay out of current value. GMis supposedly going to investigate the vehicle and the cause of fire. Lifter issue is widespread on these engines. Many lawsuits. Vehicle is still in dealer lot burned up waiting for gm to investigate it. I am getting no resolution from GM to help me fully recover from this with new vehicle. If no one had told mechanic that vehicle was on fire who knows if he would have gotten out safely before engulfed in flames. I could not upload additional photos due to site no working.

May 26, 2024

Fuel injector failed and pumped too much gas into cylinder causing gas to get into engine oil and ruin engine. GM claims they are building the replacement engine, but won't give any estimate of when it will be fixed. Other dealers that are receiving these engines will not sell the engine to my dealer. I believe there is a bigger problem that GM will not admit to and they should be held accountable. Four months is too long for this situation to exist!

Mar 28, 2023

The water pump burst without any warning.