Just turned 80 K Only external filter change. Should I do Internal? Flush Drain and fill?
Thanks Gary

Drain and fill is all that's needed. No need to do the internal filter.
Use a DEX3 type fluid fluid with TES-389 or TES-295 certification to be seal safe.

Drain and fill is all that's needed. No need to do the internal filter.
Use a DEX3 type fluid fluid with TES-389 or TES-295 certification to be seal safe.



x2

when is it required to do the internal filter? I had my tranny fluid changed out at the dealer and they only did the external filter.

80k miles? Dont be a fool, and spend $100 on your Allison....

http://www.merchant-automotive.com/allisondeeppankit.aspx

The Amsoil "Torque Drive" product has way better shift characteristics than Dex III.

Treat your truck well..... it will repay you two fold.

when is it required to do the internal filter? I had my tranny fluid changed out at the dealer and they only did the external filter.

The internal filter only needs to be changed at a rebuild or if you get some serious contamination. It's really really just a rock catcher in terms of filtration.

I'd be more worried if the dealer put the magnet back on your spin-on...