Low RPM Growling/Grinding Noise

[Aelfwine]

I had this problem for a while now and can't figure out the cause.
2002 4Runner 4x4 with 5speed swap.

It mostly happens in 3rd, 4th or 5th gear. In 2wd anywhere lower than 2000rpm I can hear a growling noise only when accelerating. It smooths out at 2000rpm and higher and disappears. Today I drove around in 4wd and noticed none of that sound. There is a little bit of vibration which is probably normal but no noise. I don't know what this means. What should I be looking at? I'm guessing its a drive line noise? I recently replace rear drive shaft because it was bent. Rear axle has been making a little noise lately but it seems like sound is coming from tranny/tcase or front drive shaft area.

 

[Skinfaxi]

I had this problem for a while now and can't figure out the cause.
2002 4Runner 4x4 with 5speed swap.

It mostly happens in 3rd, 4th or 5th gear. In 2wd anywhere lower than 2000rpm I can hear a growling noise only when accelerating. It smooths out at 2000rpm and higher and disappears. Today I drove around in 4wd and noticed none of that sound. There is a little bit of vibration which is probably normal but no noise. I don't know what this means. What should I be looking at? I'm guessing its a drive line noise? I recently replace rear drive shaft because it was bent. Rear axle has been making a little noise lately but it seems like sound is coming from tranny/tcase or front drive shaft area.

I have the exact same noise in my 5 speed. I was concerned at first, but it's been two years and I haven't noticed any other ill effects. I figure it's a waste of time to worry about it until it's bad enough that I can actually figure out what the problem is.

 

[Aelfwine]

I have the exact same noise in my 5 speed. I was concerned at first, but it's been two years and I haven't noticed any other ill effects. I figure it's a waste of time to worry about it until it's bad enough that I can actually figure out what the problem is.

I guess I could just convince myself that its normal but its driving me nuts every time!

 

[Skinfaxi]

I guess I could just convince myself that its normal but its driving me nuts every time!

I rarely drive in that engine speed range anymore. I used to keep the revs low for fuel economy, but I did a lot of MPG investigation with my scangauge, and realized that the 5VZ really isn't happy below 2k for anything but constant speed cruise. My MPG actually increased when I started shifting at 2500-3k rather than lugging and shifting at 2k or lower. So, I rarely even hear the nose anymore.

 

[Yoter]

I have not had that noise in any of my 3 4runners, I would look into it! It does not sound normal at all.
Sorry I have no idea as to what it could be but I just don't think ignoring that noise is a good idea!
Do you have a multi mode transfer case?

 

[eurasiaoverland]

I've had it before on my Hilux. I had a kind of gentle whirring / meshing sound which was at low RPMs only. I am not sure exactly of the cause, but believe it's the sound of the radial springs in the clutch as they start to wear. Probably nothing to worry about until you start to get a lot of clutch juddering.

 

[Aelfwine]

I have not had that noise in any of my 3 4runners, I would look into it! It does not sound normal at all.

Sorry I have no idea as to what it could be but I just don't think ignoring that noise is a good idea!

Do you have a multi mode transfer case?

I agree, I wanna fix it. I have the multimode tcase.

I still don't get why it goes away in 4wd though...