Help Needed Identifying Mystery Smell After Driving (1 Viewer)

[LXRookie]

Hi all,

I've been noticing a smell somewhat similar to gear oil after driving. No visible diff or transfer case leak. I decided to change the diff/and transfer case oils early to check the levels thinking a leak there was the most likely thing but they were all all tip top. The smell is similar to gear oil, but lacks the strong sulfurous punch. No visible leaks anywhere on the vehicle. It seems to be stronger near the rear. Please feel free to point me in the direction of a relevant post if I missed it in my search.

 

[kz195688]

May I suggest you check the front and rear differential breathers (mainly the rear since you mentioned the smell may be stronger near the rear). Make sure they are working and not clogged. In the rear, check the brake shield area on both sides for any oily spots/area which may indicate a rear axle/seal leak.

 

[paflytyer]

When your charcoal canister becomes overwhelmed... especially in the heat, the fuel vapor has an odd smell. Almost like glue. Check your gas cap when you smell the smell. Before opening it, look down the side of the truck and see if you can see the telltale sign of fuel vapor escaping out of your filler door. If you decide to open the gas cap, do so slowly. It'll be built up with pressure. You may even hear the gurgling coming from your tank/filler tube.

 

[thebeedeegee]

I've smelled something similar after greasing my U-joints. The grease was flung around and got hot when I drove.

 

[riffman12]

have you greased your driveshaft recently? grease can be splattering onto hot exhaust

otherwise check your CV boots. Sometimes they crack and fling grease onto hot stuff as well

 

[codertimt]

Check where steering linkage goes into rack...above drivers CV joint. I had what I would consider similar smell(kept checking diffs) that was a seal leaking there, dripping onto CV, being flung on manifold and burning off...

 

[LXRookie]

Thanks all. I'll be under the truck soon and will check all the CV joints, steering rack, and drive shafts. I'll check out the fuel pressure buildup the next time I drive it.