2006 SR5 - strange smell when downshifting

[NHevergreen]

We just picked up a 2006 SR5 V6 (< 75K miles) in NY and drove it home to NH. The fastest way from the Adirondacks to home involves a LOT of steep climbs. Early on in the trip I noticed a strange smell (hot, not unpleasant) when the auto transmission downshifted on a hill climb. Later in the trip I noticed a different smell, almost chlorine-like, when the engine and transmission were under stress. The smell dissipated immediately when the transmission shifted into the next higher gear. I didn't notice any shifting problems other than the smell. Any thoughts on what the problem might be?

 

[Upchk]

Wow... I've noticed the same smell but mines a v8... I'd love to know what it is...

 

[LobstaMobsta]

We just picked up a 2006 SR5 V6 (< 75K miles) in NY and drove it home to NH. The fastest way from the Adirondacks to home involves a LOT of steep climbs. Early on in the trip I noticed a strange smell (hot, not unpleasant) when the auto transmission downshifted on a hill climb. Later in the trip I noticed a different smell, almost chlorine-like, when the engine and transmission were under stress. The smell dissipated immediately when the transmission shifted into the next higher gear. I didn't notice any shifting problems other than the smell. Any thoughts on what the problem might be?

Could have been engine cleaner or "shine" that the dealer would use to dress it up, maybe got on exhaust manifold?

 

[NHevergreen]

Could have been engine cleaner or "shine" that the dealer would use to dress it up, maybe got on exhaust manifold?

We bought this through a private sale, and the seller (original owner) didn't clean the vehicle up at all. I pulled the Carfax report and there aren't any clues there.

 

[R.A.]

Sounds/smells like a "precursor" to the rotten egg/sulfur smell.

I've noticed the same odor when I drive normal and lightly accelerate up hills or pass someone. It's not a rotten egg odor/sulfur smell, just a hot almost ammonia smell.

However, if I put the pedal to the medal, like when I pass someone, sometimes I get the sulfur smell which varies in intensity.

Sounds normal to me. I've had an 04 and an 07, both vehicles performed the same. The 04 had the cats replaced under warranty, but the smells returned.

I wouldn't worry about it.

 

[Love4myRunner]

It's probably something the old owner did. Maybe they cleaned something before they sold it like the area where the oil filter sits or maybe they sprayed bleach to get rid of a bad odor. Sometimes you notice smells that aren't there when you slow down. Doubt it was due to downshifting.

Example. I'm sure this has happened to most people. Your driving at a good speed but the moment you start to slow down you notice an odor like gas, burning oil or, asphalt. Most of the time you can clearly see the car in front of you smoking after you notice the smell. lol But sometimes you find out due to parts being heated up it is actually your car.

Over worked transmission smells like complete crap so I don't think you have anything to worry about there. You will find out soon enough that you new Toyota is a highly reliable vehicle. Congrats and welcome!

 

[NHevergreen]

I spoke to the mechanic who has worked on the truck since the original owners bought it new, and he wasn't aware of any problems. It's going into the shop for a thorough inspection by my mechanic, and I hope we can pinpoint the source of the problem. It drives beautifully, and I'm keeping my fingers crossed that it's nothing major. We have a '99 SR5 with 230K miles on it that is still being driven daily, and we just replaced the original transmission in December. We're an all-Toyota family ('99 and '06 4Runners, '09 Avalon, and '07 Rav4) and we love the reliability!

 

[03_4x4Runner]

I have had grease get on the muffler that slung off the driveshaft after greasing it that smelled for a while.

 

[Greydog]

The ammonia or rotten egg smell is the odor produced by the cats when heated up above cruising temp.

Many toyotas do this. They used to be warranted but it ended since its not a functional problem.

Mine seems to draw the odor forward into the vehicle with the rear window up or partiall open, but very little comes in when the rear window is all the way down.