Currently on a trip in the Smoky Mountains area. Our 15 is experiencing a heavy burning smell after driving up this STEEP driveway to our vacation rental. I don't smell it while in town driving around here. On occasion, at home, (flat roads), it has a mild smell. It has 129k on it. The trans fluid, front/rear diff, and transfer case fluid were changed around 90k. I have an appointment with Toyota next Saturday to get at least the transmission fluid changed again. We had the cam tower leak issue; had it fixed at Lexus--twice, because it leaked as soon as we got it back, so they re-did it. I didn't see anything there. I saw some dirty dried oil type residue around the crank case; so I'm wondering if it has that leak too. I know that's common, but nothing fresh. I like this car, but am $7k+ into it. I guess we'll just keep fixing it vs buy a $53k Grand Highlander, which my wife really likes. I don't want to give up the GX. I crawled under it and didn't see a plastic bag or anything stuck to it. I've used 4 Lo maybe twice here. It gets up the driveway fine in normal 1st gear and I use 2nd gear when driving down the hills to avoid wear on the brakes. Anyone had something related to this issue? I figured all the main things to check have been looked into, since I see no active fresh oil leaks.

 

Check the cam towers and valve covers to see if there is oil leaking on the exhaust manifolds.

Also were the u-joints greased recently? I have seen excess grease being thrown onto the exhaust system.

 

Cam tower leaks were repaired twice as I mentioned in the original post, and I’ve looked under there and saw no leaks. They sealed everything well after doing it twice, and the valve cover gaskets were included with that. Not sure if the dealer greased the u-joints. I guess I will find out next Saturday what the issue is. Wife is fed up with it, I love and hate it. I want to keep it and see so many people with well over 200k and minimal issues. It’s frustrating​​​​​​.

 

Check to make sure you don’t have any dragging calipers. Wheel/rim will be noticeabley hotter than others. A cheap thermal gun will conform. I replaced a right rear caliper on my ‘12 that was dragging back in spring. Vehicle had around 93k miles.

 

None of the wheels were hot. Checked twice; already replaced the LR caliper a while back, as it was smoking. Doesn’t appear to be the brakes.

 

How many miles ago were the cam towers fixed?

Just wondering if some residual missed cleanup on the backside of engine is making to exhaust once it gets warmed up

 

Just over 10k ago, and the 2nd time the RO stated that they pressure washed the engine and made sure it got hot on the test drive. I checked under there before the trip and didn't see any leaks but did see where they made sure to put a lot of sealant at the heads. We just drove 500 miles home through hilly terrain back to our flat area and 0 burning smell whatsoever. I'm still taking it in to get the fluids changed next Saturday. It's been 40k since the last time but I towed a car once and this trip put some strain on it. I'm sure some on here that live in a mountainous terrain spend a fortune on maintenance and wear/tear items.

 

It's possible that you are just smelling normal exhaust emissions from the extra stress being put on the motor from driving up a steep incline.