4.10? Or 4.56?

What are we talking about then? What did you put in yours?

 

A 3rd member from a 2014 4x4.. 8".

 

And the same pumpkin previously housed a 7.5" 3rd member?

 

https://www.drivetrainshop.com/Toyota_7_5_s/120.htm

7.5 was only used until 2006.

 

Oh crap, really? Mine is a 2010, but since the axle code starts with A, I've been assuming it was a 7.5".

 

Ok, Gentleman!
I heard all the rumors about the different third member in Tacoma's. It took a phone call to a Toyota engineer! That took a long time to find out the truth about the 3rd members in Tacoma's.
The Third member in the 2005-2015 are all the same but for the E-locker and the X-runner w/ 3.15 gear & the 2.7L 4x2 manual trans w/ 3.31 gear. The housing with the 3.15 & 3.31 gear will not expect any other gears. The 2 Gen Tacoma, the 1st Gen Tundra and T-100 take the same Third member. So from 3.58, 3.73, 3.90, 4.10,< these are OE gears I believe 4.56, 4.88 & 5.29 will also fit. But truthfully I don't remember off the top of my head if there are any other gears that fit!
The 3rd gen Tacoma 3.90's or 4.30's will not drop in as they are 8.75". I think there's a lot of confusion because many call the gear that fits into our 3rd members a 8.4" gear when it's truthfully an 8" gear.
Oh, for Third member changes the OEM seal needs to be soaked in water before used / installed! Ask me how I know!