Does anyone ever get a burning rubber smell at high RPM?

[repo]

For the last couple of years when I am going up steep hills or passing people on the highway I have been getting this burning smell. I can't find anything obvious, there's no leaks, the brakes aren't sticking or anything, don't think it's driveshaft grease getting burnt, don't think it's the tires because it happens in the rain and going slow on hills. The transmission fluid looks and smells fine (just did a drain and fill). The smell goes away immediately when I let off the gas. I think it might be the catalytic convertor burning off something at high temp? There's no power loss that I've noticed. Am I going to need a new cat soon or what? I've replaced the upstream O2 sensor but not the one behind the cat which has 240k on it by now.

 

[alumarine]

On my current 3rd gen and my last two 2cnd gens I would sometimes notice a faint smell of what seemed like burning rubber when I got out of the truck. It seemed to come from the back.

I could never figure it out and eventually stopped thinking about it.

 

[4Rubber]

I get this as well. I live at the top of a steep hill and whenever I park and get out there is a strong burning rubber smell. I thought it was coming from a rear axle seal leak but it persisted after I fixed that. It bugs me and I’m Interested in hearing more replies on this.

 

[grokglock]

The only time I ever smelled something like that was when my transmission started to take a shit. 2 weeks later I was getting it rebuilt.

 

[Ryance39]

I tend to notice this smell when I get out of my 4runner after driving it a while. I feel like I’ve smelt it in the front, or at least right around the front door/wheel well.

Initially I thought it was the valve cover gaskets, replaced those, still smell it.

Curious what others have experienced.

 

[2003-4x4runner]

The burning rubber smell is common on the 4th and 5th Gens. It could be from the rubber mounts on the exhaust. That's my guess. Some people said it could be from the grease coming off the u-joints and hitting the exhaust.

I noticed the smell when I 1st bought my 4th Gen back in 05 and it still does it once in a while when the engine is under a heavy load.