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2025 Suburban 5.3 V8 vehicle Notice how the sound is a rhythmic, metallic knock that seems to originate from the driver-side bank. It is most prominent when the vehicle is in Gear (Drive or Reverse) with the brake applied, especially after the engine is fully warmed up from a long shift. One tech says 'Lifter', another says 'Bottom End', and another says 'Torque Converter'. I would appreciate it if you could listen and let me know if this sounds like the typical L84 lifter failure or something else.

Just installed s&b cai, and truck stalls out after start, when it doesnt it idles rough and sometimes kicks when starting to drive, it seems alot slower and is throwing me a check engine light please help! What do i do

Short version: 2018 silverado 2500 6.0 intermittently misfiring on bank 1. Holes 1/3/5/7. Changed 02 sensors, plugs. coils, catalytic converters, spark plugs. Once the truck is above 1300rpm or so, it doesn't misfire at all. Cannot seem to find any relation between whether ambient temperature is hot or cold or when engine temperature is hot or cold. Long version: Hey Y'all, I bought a used 2018 Silverado 2500 with a 6.0 L96 "G" about a month ago. Used from a sales lot. 160km (100,000 miles.) After driving about 200 highway miles or so, I was at a red light, and it was idling (burbling and chugging) a little weird. When I went to leave the red light, the engine was a bit hesitant, but once above 1200rpm or so, it drove fine. Over the next few days, It did the same thing intermittently and ended up throwing some codes: P0420: Catalyst system low efficiency P0137 H02S Circuit Low voltage sensor 2 P2097 Post catalyst fuel trim system high limit bank 1 P2099 Post catalyst fuel trim system high limit bank 2 P0300 random/multiple misfire. However, once rolling, it performs fine with no drama. The dealer gave me a 2 year unlimited mileage powertrain warranty through a 3rd party company. The warranty company does not pay for diagnostic work, just part changing and part cost. In order to get this warranty, I agreed to do oil change/spark plugs/air filter. For peace of mind, I ordered new 02 sensors (2 up 2 down) 8 new plugs (stock replacements) ignition coils and ignition wires. Once the parts came in, I got underneath and changed the 02 sensors. It looks like they had been changed at some point because they were aftermarket sensors. I started the truck up and cleared the codes. It ran fine for 10 minutes. I had my fiancée come out to back the truck out of the garage (I was filthy) and as soon as it went in reverse, it started idling like dog sh** and stalled out. I started it up again and we coerced it out of the garage. At this point I was tired and cranky (up for 24 hours with 12 hours of work in there.) I was in no mood to carry on with working on it. I took it to a shop and we plugged the Gucci Snap on scanner into the truck. It showed it was misfiring on 1/3/5/7. All bank 1. Bank 2 was fine. The mechanic/shop owner and I decided to have the coils/plugs/wires changed and see what happens. He called me later that evening and said the truck was running like a top. He had his datalogger on and it hadn't recorded a single misfire. I went to the shop and saw the truck had been running for about 40 minutes without recording a misfire. Drove it 10 minutes to a friend's house and had dinner. It worked fine. No idle or low RPM acceleration issues. When I left his house, I let the truck run for a minute and it started repeating it's prior behaviors. Did some studying at youtube university. Added a 2nd ground off of the coil harness to ensure it was grounding properly. No change. Cleaned MAF and throttle body, no change. Called some friends that are smarter than me. We concluded it may be the catalytic converter. While the truck wasn't short on any power.. It was a company truck (seemingly well maintained) that likely idled a lot. There are nearly 7000 hours on the truck. Not sure if that's high hours for the mileage. Took it to an exhaust shop and asked them to determine if the cat was pooched. They called me back and said it was. I did not ask how they determined this. Ordered a new set of Magnaflow cats (and a muffler for fun sounds.) Had them installed yesterday. Picked them up from the shop and the truck ran great. Today, it started doing the Harlem shake again. I'm guessing after this... It's got to be a wiring issue? Chafing somewhere? What makes me have a hard time believing it's electrical is that it is strictly RPM related. Idle to about 1300/1400 rpm. And intermittent. Once I'm cruising it's fine. If I am at a lower speed and the trans is in a gear where the RPM is low... it will (very seldom) struggle a little to build RPM. I've been using the gear selector a lot to keep the RPM's above 1400. I cannot seem to find a correlation between when the engine is hot/cold etc. If any of you have some insight, it would be greatly appreciated. This weekend a friend and I are going to hookup datalogger to check fuel trims, and also watch for misfires while wiggling harnesses and such. Have a great day! I'm about to lose my mind. This has been a slow process

The ‘17 Sierra 1500 6.2L idle is a little weak and its knocking or ticking some. This is the first time I changed the oil, other times by dealer. Oil pressure looks normal. I put in the required 8qts 0w/20 dexos 1 Gen 2, dipstick is fine, put on the a new oul filter (same as others), and all Acdelco as it has been. Do these motors take a little bit to run correctly after an engine oil change? Never had a motor do this.

I am having issues with my brand new 2015 GMC Yukon Denali. I was so excited to get this new car. It had a leak in the back right rear window from the start. They had to replace the entire headliner in the interior. Now I've got a shiver when in idle both in gear and out of gear. It feels like the car needs more gas. I've taken it into the shop 3 times now. The service department, after listening to my complaint and acknowledging the shiver, ultimately states that the car is "operating as designed". I've test driven a 6.2 liter Denali that does not have this issue. They've stone-walled me at GM, essentially saying they can't fix a problem that doesn't exist. Has anyone else had this issue? You would think that a brand new car wouldn't have this issue, and that they could do something to fix a rough idle. I'm beyond frustrated. I'd love to hear if anyone has the same problem.

2020 GMC 2500 gas engine. Starts good first of the day and idles smooth in park. Idle becomes rough when put in reverse to back out of garage. Smooth idle in gear after 2-3 blocks. I live in the south but it does it hot or cold weather. I've seen the service bulletin for cold weather starts and added the suggested additional ground to throttle body but no change. Truck has only had Chevron fuel. Has done this since new. Anyone else have this issue? E

2020 GMC 2500 gas engine. Starts good first of the day and idles smooth in park. Idle becomes rough when put in reverse to back out of garage. Smooth idle in gear after 2-3 blocks. I live in the south but it does it hot or cold weather. I've seen the service bulletin for cold weather starts and added the suggested additional ground to throttle body but no change. Truck has only had Chevron fuel. Has done this since new. Anyone else have this issue? E