Thumping/rumble/burbling Noise At Low Revs

[schnoutboy]

I've driven Toyota trucks for over 30 years and have been very pleased with them. I recently traded in my 1991 extra cab v6 4x4 after almost 26 years of ownership. I traded it for a 2014 Tacoma access cab v6 4x4 with a 6 speed manual transmission about 2 months ago. The truck had about 47k miles when I bought it. It is in very good shape and carfax records showed that the previous owner got the required maintenance done. After a while I noticed that it makes a noticeable thumping/burbling noise at low revs (under 2000 rpm). It is more noticeable when the engine is under load, like driving uphill. It sounds rough, but feels smooth. If I accelerate above 2000 rpm, the thumping is diminished, but I don't think it goes away entirely. I can't tell if it's an engine noise, exhaust noise or something else altogether. I wonder if the sound I'm hearing is actually from the exhaust and/or cat. I didn't see any holes in the exhaust and it looks stock, but it does sound almost like an after market exhaust, more of a rumble/burbling sound. Maybe its always there and I can only hear it more clearly at low revs going uphill. I've searched here and all over the web and haven't found any definitive answers. Has anyone else experienced something like this? Is it an indication of a minor problem or am I in for some major repairs? I don't know if it matters but I do live at about 6000 feet and drive at elevations varying from about 4000 feet to 9000 feet. Thanks!

 

[kennythewelder]

Elevation should not matter. A video of this would be a help. Also if you have a go pro, this can be a very good tool to help find things like this. Secure the go pro under the truck where you think the sound is, and move it around to different spots to help you pin point the noise, but like I said, make sure the go pro is very secure, and won't get knocked off while you are driving.

 

[schnoutboy]

Thanks kennythewelder. I'll try to do a video. The sound is really obvious to me, but I'm not sure how well it will be picked up. I don't have a go pro, but I can see where that would help locate the sound. I know that there are several go pro models. Is there one that you would recommend?

 

[kennythewelder]

LOL like you I don't have a go pro ether. I just hang the wife out the bed of the truck when I drive,,, OK I'm just kidding about the wife. Truth be known though. I have seen some video where they used a go pro before, and it is a big help. I can be hard even in a video to figure out what a sound is, but a video is a lot better than a description.

 

[tbplus10]

I'm telling your wife Kenny, be ready for a week+ on the couch.
What your describing sounds a lot like a blown exhaust gasket, don't hear of that problem much these days since most people don't run headers.

 

[kennythewelder]

LOL , I told her that a while back, about her being my go pro, She just laughed. She knows how I am. Funny you mention headers. I finally fixed my header leaks on my 97 Silverado about 2 weeks ago. It's the best the truck has sounded sense I put the shortys on it about 3 or 4 years ago. Those old 350s just sound so good with the rite exhaust.

 

[toyotafan]

LOL like you I don't have a go pro ether. I just hang the wife out the bed of the truck when I drive,,, OK I'm just kidding about the wife. Truth be known though. I have seen some video where they used a go pro before, and it is a big help. I can be hard even in a video to figure out what a sound is, but a video is a lot better than a description.

Wow.

 

[kennythewelder]

Wow.

I have had my wife drive the truck, while I have hung out of the window, moved around in the cab, and even rode in the bed moving around in it, while trying to pin point where a sound was coming from. Of corse this should be done on a back road somewhere, and one needs to be extra carefull. The last thing you want to do is fall out of a moving truck, or get hit by a stationary object, or even worse, a car or a truck . This is not the kind of thing, you tell your buddy, hold my beer and watch this. Ha Ha. The go pro is a lot safer and you can attach it in places that a person just can't get to.

 

[tibadoe]

.............hold my beer and watch this. Ha Ha............

I remember a few times I said "watch this".

 

[toyotafan]

I've driven Toyota trucks for over 30 years and have been very pleased with them. I recently traded in my 1991 extra cab v6 4x4 after almost 26 years of ownership. I traded it for a 2014 Tacoma access cab v6 4x4 with a 6 speed manual transmission about 2 months ago. The truck had about 47k miles when I bought it. It is in very good shape and carfax records showed that the previous owner got the required maintenance done. After a while I noticed that it makes a noticeable thumping/burbling noise at low revs (under 2000 rpm). It is more noticeable when the engine is under load, like driving uphill. It sounds rough, but feels smooth. If I accelerate above 2000 rpm, the thumping is diminished, but I don't think it goes away entirely. I can't tell if it's an engine noise, exhaust noise or something else altogether. I wonder if the sound I'm hearing is actually from the exhaust and/or cat. I didn't see any holes in the exhaust and it looks stock, but it does sound almost like an after market exhaust, more of a rumble/burbling sound. Maybe its always there and I can only hear it more clearly at low revs going uphill. I've searched here and all over the web and haven't found any definitive answers. Has anyone else experienced something like this? Is it an indication of a minor problem or am I in for some major repairs? I don't know if it matters but I do live at about 6000 feet and drive at elevations varying from about 4000 feet to 9000 feet. Thanks!

Any remedy to this?