Re-gearing my 3rd gen

Ya mine are the 3.9 AT

 

So I might be mistaken, but I think there was someone talking about humming gears?? I’m experiencing this in the front around 30 mph when I push the gas a little and take it off. Any help? There’s about 18 miles on the front so far

 

Mine humms a little bit on deceleration from 30mph to about 15. no biggie, like a descending whistle, or a bomb falling thru the air. lol I've heard others whine like a 747 ... not on taco's per se, but like in a Dodge Ram or similar.

 

Ya it’s really weird, but I figured out what it was. I did some research and everyone was saying that it went away when they put it in 4wd, but that’s when I was having the problem. I don’t hear it in 2wd. So I called he shop and he said everything should be fine. He explained that it was turning a lot faster and how it’s not really meant to be driven in 4wd on the concrete. So it’s kinda stupid, but I just wanted to make sure I didn’t mess anything up. I’ve never had a 4wd or awd vehicle, so all of this is new to me. Sorry for the stupidity lol.

 

https://youtu.be/-mGV41V_TEo

 

Hard (for me) to hear the hum. Do you find it really noticeable? I guess you must or you wouldn't post. Are these Nitro 4.88? If the noise is significant the gears may not be set-up correctly. Getting the shim right in the front can be tricky. If it were my truck I'd find a shop with diff expertise and have them check it out. I'm curious what other people have to say, but that's a bummer bro. Good luck.

 

I found this on another thread - I don't know if this info is accurate, but I thought I'd pass it along:
https://www.tacomaworld.com/threads/installed-4-88-gears-in-my-2016.455190/page-43

QUOTE FROM POST #843: From what I understand humming comes from improper spacing/bad installation. A friend at Toyota said the shims for the 3rd gen are hard to come by. When he was re gearing mine he said there were none left in the country. If I had to guess I'd say that these shops can't get the proper shims in and are calling the spacing "good enough" and hoping for the best.

QUOTE FROM POST #847: Attention everyone looking to regear a TRD Sport auto V6 or a SR5 auto 4cylinder!!! The master install kit coming from Nitro DOES NOT HAVE THE CORRECT CARRIER BEARINGS!!! As of right now, getting the correct ones is an act of Mexican congress cause they are not a US made part. I ended up having to use a pair of front carrier bearings and shave a half inch on either side of the axle housing to stuff everything in. If you do a regear, DO NOT REMOVE THE STOCK CARRIER BEARINGS!!! They must be reused. I informed Nitro they needed to put this information on their website so others don't run into the same issue as me. As far as the gears go and drivability? It's great!!! I have only about 20 miles on them as of now but will be driving 150 tomorrow and 300 miles on Saturday so we'll see how everything breaks in...

 

Ya it’s hard to hear with the exhaust and tire noise. But it’s right when I let off the gas and then again right when I roll back onto it. Only around 30 mph, and the max is 40. The guy from the shop said it was completely normal for it to do that because it’s spinning a lot faster than the normal gears and it’s really not meant to be driven in 4wd on cement. He said he heard the same thing when he test drove it after it was completed... So my impression is that it’s all good.

 

Yes! He had to do the same for mine, but that’s only for the rear, which I’m not having issues with. And it’s only in 4wd not 2wd.