Top end or bottom end knock?
Thread Starter
On The Tree
Joined: Mar 2011
Posts: 142
Likes: 19
From: Beaufort, SC
Top end or bottom end knock? Trying to figure out if this tapping/knocking noise is valvetrain or rotating assembly. Sorry about the video. I know it sucks and you have to turn the volume way up. I had to put the phone down by the floor board to pick it up without getting drowned out. Its much louder in person, and especially when warm, outside the truck. In this video its a cold start (75* ambient) and I was just moving it around the yard.
You can really hear it from about 0:50 to 1:00 in. Its most noticeable 1500-1800 rpms, which is were it was in the video from 0:50 on.
You can really hear it from about 0:50 to 1:00 in. Its most noticeable 1500-1800 rpms, which is were it was in the video from 0:50 on.
Last edited by Zac28; Mar 7, 2024 at 02:38 PM.
Thread Starter
On The Tree
Joined: Mar 2011
Posts: 142
Likes: 19
From: Beaufort, SC
I think the "lifter tick" you heard is the noise. In person its pretty loud. It sounds very much like a diesel "clacking". Its just hard for my phone to pick it up evidently. Here is another video that will hopefully make it a little easier to hear. But I think by you saying lifter tick it answers my question. I think its in the valvetrain, but my brother thinks in the bottom end. He thinks that because it is more noticeable under truck, but I think that's just because of the exhaust. I was just reaching out to get others opinions to get a better idea.
Joined: Apr 2006
Posts: 3,890
Likes: 1,137
From: Grand Rapids, Michigan
I recommend this a lot, because it absolutely works - Go to Harbor Freight and buy yourself a cheap mechanic's stethoscope, and listen around the engine. It won't take long to determine where the sound is coming from. I still don't think it's in the bottom end, the sound would be more frequent, and much deeper. Your cam turns at half speed, you know? If you get under the truck and stick the end of the stethoscope on the oil pan rail, you'll know right away if you have a bottom end knock.
Thread Starter
On The Tree
Joined: Mar 2011
Posts: 142
Likes: 19
From: Beaufort, SC
I recommend this a lot, because it absolutely works - Go to Harbor Freight and buy yourself a cheap mechanic's stethoscope, and listen around the engine. It won't take long to determine where the sound is coming from. I still don't think it's in the bottom end, the sound would be more frequent, and much deeper. Your cam turns at half speed, you know? If you get under the truck and stick the end of the stethoscope on the oil pan rail, you'll know right away if you have a bottom end knock.
TECH Resident
Joined: Jul 2009
Posts: 751
Likes: 322
I can barely hear it but it sounds like a stickey lifter. I'd run some transmission fluid or seafoam through the crankcase for a day. I've gotten a lot of trade ins over the years with the same noise, usually a lot louder. I've saved some bad sounding trucks using this method that were destined to the junk yard but ended up on the front line instead 
