Slight grinding felt thru gas pedal...?

So, driving at typical city speeds, 30-50mph, I can feel a very slight grinding sensation thru the gas pedal. It is ever so light (barely noticeable) and I thought it was all in my head until the wife drove my drunk ass home last night and mentioned it. Seems to be pulsing at 1.5 second intervals, and last for a quarter second and does this while foot is on accelerator maintaining speed. 75k miles on truck, no lift, replaced shocks, new stock size dtrac tires and alignment a couple months ago but think this was present before that. Thoughts?

 

I had stock Michelin Ltx ms2 tires on her before. You really think tires are responsible for a grinding/pulsating thru gas pedal? I was thinking rotors or wheel bearings but that’s not based on anything...

 

Front diff bearing. Search for differential growl. There is a TSB on it.

Put it in 4wd and see if it goes away.

 

Bad wheel bearing are also most noticable during a sweeping turn. Like a on ramp or off ramp.

A bad bearing will creep up on you too cause the typical sound on makes, the roaring type, is a gradual increase. It kinda tricks your ear into forgeting what it used to sound like before it started to fail.

On a safe road that you wont have other drivers on you can try the above method. You only have a short moment to hear the "roaring" sound, though.

You dont have to be going fast either. 25 mh is probably more than enough.

Sway from the left lane over into the right lane and back. The weight transfer is what will cause the bad bearing to be audible. So when swaying left tbe weight will be loading the bearings on the right side.

 

https://eastcoastgearsupply.com/files/PDF Files/tsb-0121-08-t9r-front-diff-growl.pdf

My 2010 did it at about 80k miles. Toyota wants to replace the entire diff. There is a company that makes a replacement bearing that is NOT a needle bearing like stock. It was $50 plus install, which was about $500 in a high labor cost area.

 

My 2016 is doing the same thing with 48K on the clock. I'm 99% sure it's the needle bearing, which will be replaced with the ECGS bushing this week when I have the 4.88's installed. I'll post an update.

 

Absolutely no sound, barely even noticeable thru gas pedal...

 

Thing is, there is no audible sound, it’s so subtle I can barely feel through gas pedal when wearing flip flops, Can’t feel it when wearing work boots, it’s that subtle of a “feel”...

 

Would be a good idea to inspect and grease the u-joints, and inspect the steady bearing (AKA carrier bearing, hanger bearing) on the driveshaft.

 

Yeah, not the typical signs of a bad wheel bearing. Being easy to test made it worth checking though.

Sounds like couple other guys here are familiar with a good possible cause/solution. Good advice is abundant around these forums, thankfully.

 

Did you ever resolve this? My truck is having the same symptoms and I'm curious if the ECGS bearing replacement solved your problem. Only difference with mine is its gotten louder and I CAN hear it. Its the cyclic "woo woo woo" sound. Also the noise/vibration usually goes away after i drive 10-15 miles.

 

Not in any sense that I found something “wrong”. I’ve read of many others with this issue, mine seems to be resolved with a fresh oil change. Also found I lose oil between changes and when the oil gets lower than half way between the dots, it’ll get a bit louder and let me know to add. Good luck

 

Just to follow up on this, I did the needle bearing replacement with the ECGS bushing and the noise is gone. I thought I would confirm this for anyone looking at this forum because the symptoms my truck has were not exactly matching the TSB. I was experiencing noise and vibration around 45-50 mph, but nothing below 30 mph. Also, the vibration would usually go away after i'd been driving the truck the 10-15 miles.
Also I thought I would share some of my mistakes to help the next person. DONT push the axel seal in too far, it will leak. It should be flush the the outside of the differential housing. DO purchase the ECGS installation tool. Its worth the extra money even if you think you have a socket that will do the job. DO be extremely careful not to damage the axel thread when hammering it in.

Thank you all for all the help! and good luck to the next ones who attempt this repair!