rumbling sound from 07 Tacoma passenger front side.

Hi, I have been looking around and haven't seen a similar question. The problem in my 07 Tacoma 4.0L with the A750F transmission is when I get to around ~1,100 rpm's, ~35mph and in 5th gear, I hear a rumbling sound like im going over rumble strips. Sometimes its louder and sometimes it is on the lower side sounding. When it happens I pop it into 4Hi and it still makes the sound. I also drove a 2013 trd offroad and base sr5 and both of those displayed the same rumbling sound under the exact same conditions. What could it be? I'm thinking of taking it to the dealer.

-euth209

 

If you drop to 4th or 3rd does it stop?

 

when I pop it into 4th or 3rd I can't reproduce the rumbling. Also on a cold start, the sound happens a lot more often.

 

U joints need grease, maybe

 

my suggestion is to pull the two bolts holding the air intake horn to the right fender and take that part off for a day or two see if the noise goes away.

Could be the cheap foam they put on the horn where it goes into the fender, you'll see it when you remove it, I replaced mine with better foam and the noise went away.