1997 GMC transfer case fill hole allen key size?

[Chris B.]

Does anyone know the size of the allen key for the fill hole on a 1997 1500 GMC Sierra? Thanks!

 

[Clevy]

Isn't it a 3/8 square. Like the end of a ratchet.

 

[BobsArmory]

Both Diffs on my wifes car take a 3/8 allen key and the transfer takes a 3/8 square ratchet. 07 Cadillac STS AWD.

 

[Chris B.]

On my transfer case it is an alen head.

 

[Chris B.]

bump!

 

[The_Eric]

10mm

 

[Chris B.]

Thanks! I'll now have to go buy one......