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Showing results for tags 'knocking'.
Found 8 results
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I just bought a pre-owned 2015 Yukon Denali and I Love it! I've been waiting for the feel of a big V8 engine with 4 wheel drive so this girl can dirty on any road.. It's beautiful and I'm SO happy to own a sexy Denali. I've only had it for two weeks so I'm learning every thing about it with each drive. So far the engine purrs and all gauges read level. It's got 98k mi on it so I'm expecting it to have some wear and tear. So just yesterday morning I pulled away from a stop sign and gave a good rev got up to 50mph in a few sec... and as I approached a slow zone I took my foot off the gas.. lowered speed to about 25 then gave it a little more gas while going up a slight hill in the road and I hear what sounded like a knocking noise. I took my foot off the gas and the sound went away. So on the drive home where I have to ascend up to about 2200 ft elevation it did it again as I was coasting and had to accelerate from 25 to around 30 mph I kept my foot on the gas this time (engine sounding smooth as silk) and continued uphill about 45mph and the sound went away. It's always a short knocking/rattling sound. Not in the engine but below me, definitely upfront. I've got an appt at GMC next week but until then I'd love to figure it out. Not sure what other details you need but any one got any idea? Thanks everyone! -Dia -
About 1 year ago I replaced the engine in my 1989 suburban v2500 with a 5.7L tbi engine in it, I used another chevy 350 from summit racing and used most of the old Accesory drive then, about 6 months after I completed the build it noticed a loud rattling noise that sounded like detonation to me but only under low speed acceleration and it would stop when I let my foot off the gas, so I began troubleshooting the issue. I replaced the egr valve, put colder spark plugs in it, replaced the knock sensor, tried high octane fuel, retarded the timing adjusted the valve lash and now I am lost, the noise only gets worse the more I drive it. Any Ideas? -
I have an 06 Silverado with 215k miles. Has the L33 Aluminum Block 5.3 in it. It runs great, has good power, but has an odd ticking/knocking noise. It doesn’t make the noise until it’s been running for about a minute so I don’t think it’s exhaust. I also do not think it’s a lifter because it sounds more lower end towards the rear of the engine. Has anyone had any experience with these L33s knocking? It has been making this noise for a while now and it’s very annoying/embarrassing. I’m not sure if oil has anything to do with it but I use penzoil 5w30 full syn. Let me know if you have any ideas, thanks.
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454 Vortec Tapping and Knocking
RW22 posted a topic in 1988-1999 Chevrolet & GMC C/K GMT400 Platform
I have a 1997 k2500 Suburban with the 7.4 vortec. It is a 290,000 mile engine and I was recently doing some work to it. I put new injectors, valve cover and upper intake gaskets, distributor, plugs, wires, and a fuel presssure regulator. This engine was fine before and the only reason I had done this work was because it was cranking for about 5-8 seconds before it would start. When I put everything back together, I got the timing as best as I could (I do not know how to properly time these newer engines) and started it. Immediately, the engine was shuttering and I could hear what sounded like a lifter tap. It was idling very rough and after about 4-5 min a louder knocking sound started up. I immediately cut the engine and checked the oil for metal, and there was none. I am simply baffled at this as I didn’t touch anything when I had the valve covers off. My only two ideas are this. 1) it is not timed right, and I need to figure out how, or 2) the old distributor had some wear on the gear, and possibly the cam has the same wear and isn’t working right with the new distributor. Any help on this would be greatly appreciated. Thanks. -
Took my 2017 Chevy Silverado z71 to the dealer today . Engine was ticking on top end sounded like a lifter tick and slight deeper knock in bottom end . oil presure was all over the place would go from 65 psi to 25 psi at same rpm. I have 44,000 miles. Has anyone else had this issue? With the strike in play who know how long I will be without my truck.
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Hey guys, I got a 2015 Silverado 5.3l. 138,250km. started ticking sometime last winter. Would happen instantly at start up and last about 5 minutes then would fade away. Sounded like a lifter. Took it to the dealer they said they couldn't hear it. Sound went away so left it. Fast forward to this winter and as Soon as the weather started to cool down I noticed the ticking again. Took it back to the dealer said they couldn't hear it again. I went and picked up my truck right at closing, soon as I fired her up the sound was there but everyone was gone so no one to hear it. I took a video. Next day I called the dealer, sent the video. Took like a week to get back to me. In the meantime I had taken videos pretty much every time I started it. Long story short after a brief fight with them about them trying to say it's normal etc they agreed that it sounded like a noise coming from the valve train. Left my truck with them, they called me said they had to change all lifters. Went to pick up my truck and on start up the sound is still there. This was a month ago. Sent more videos and a previous video from before they did the work and they are saying they can't hear it again. Took it in in person they agreed that there's an issue again and they will look at it. Now they are saying it's possible bad injector noise but they can't figure out which one ?. In the meantime I took it to another dealership they changed the vacuum pump. After that the sound changed. Now it's no longer at start up but once the truck has reached operating temperature and is more of a dull sound. Took it back to that same dealer who did the vacuum pump and they said valve train noise and deffo not injectors. But they won't work on it because the other dealer already did. They didn't change the VLOM or the cam. I had/have no check engine lights. Truck runs awesome. Sometimes rough idle. Any ideas what it could be? -
I have a 99 Silverado LS 5.3 new body style. I noticed a loud knocking noise coming from underneath the truck when I let off the gas. I thought it was the front drive shaft u joint but I took the drive shaft off and drove it and it still has the knocking noise. Changed cv axles both sides. Put new seals on the front diff. Brand new suspension. New control arms. And still can’t figure out what it is. Any guesses?!?!?!
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Low Speed Knocking - am I going nuts?
socalbrit posted a question in 2015-2022 Colorado & Canyon Troubleshooting
Our 2017 2WD Colorado Z71 with 33k miles started making a knocking sound at low speed, worst at around 20mph, sometimes more noticeable than others. First the dealer put it down to normal tire noise, then a few months later when the noise got worse said it was cupped tires and that we needed to replace them. They recommended less aggressive tires as the "stock" all terrain tires always cup and make noise apparently. So, we had a new set of tires put on and the rhythmic thumping was still there, more obvious now that it wasn't masked by tire noise. The noise seemed to come from the front of the car and was noticeable at low speed 10-20mph and would speed and slow with the car. Once you're tuned into it you can hear it/feel it around 40mph too but its more of a vibration. Took it back to the dealer and test drove, they heard the knocking and decided to replace both front hubs under warranty. When we picked the car up they said the noise was gone other than normal truck noises, on the drive home it obviously wasn't. In fact it's worse under some conditions. Now it seems that either the problem is getting worse or we're hearing/feeling things that aren't there. The knocking has become stronger but only sometimes, and at highway speeds it feels like the whole truck is buffeting and vibrating. It also seems to be slipping gears, or shuddering between changes at low revs. Having taken it back tot he dealer they say there's nothing wrong, they can't hear or feel any problems, and to be fair to them the knocking was less noticeable when I drove it with them but the vibration and shudder was there. I did ask to drive a new one so I could feel the difference and perhaps it's just normal but they didn't want to do that. I've now left it with them and asked them to test drive it more and if they're happy there's no problem then I'll pick it up and if it comes back I'll take it somewhere else for an independent test. We're 100% sure on the rhythmic knocking/thumping, especially as it's the same issue before and after the tires and hubs were changed, perhaps this is normal. As for the vibration and buffeting we're less sure, it does seem like it's slipping gears and shuddering but after so much focus listening to the thumping perhaps we're just seeing problems where none exist. Does anyone else have any similar experiences, or are we truly just going a bit nuts?
