Hissing/Whirring/Air Noise on Acceleration

Hey all.

2014 TRD OR DCSB with just under 30K miles. Meticulously maintained. All fluids (diffs/oil/trans flush) changed within the last few months.

I have a sounds on acceleration through 1st and 2nd gear that sounds almost like air sucking in somewhere. I have already checked the air cleaner box and it is secured and put together properly.

The sound only shows up while accelerating under load. Meaning....you don't hear it if you rap the engine up in neutral. Only while in motion.

I have read some posts here and there but no one seems to have settled on a good answer and most posts were a while back with earlier trucks.

Anyone have an idea of what this is? Anyone experienced it and found the issue?

Thanks.

 

I think I have the same shit on an 09 trd sport. It just started this weekend. Let me know if you find anything . I'll do you same. My neighbor that does alot of his own work said it may be the fan clutch

 

Vacuum leak?

 

All this time.......found the problem today.

Trans fluid was 2 qts low.

Had the dealership investigating again today. They checked all fluid levels. Trans was way low.

Sound is GONE!

 

whoop

 

Who did the trans flush?