Yeah, dumb question about aluminum washers and transfer case... (1 Viewer)

[DKM]

I just built a transmission fill to transfer case fill bypass hose using bsevans specs in this thread (thanks, bsevans!):

Tranny to Transfer case bypass hose

I've had a couple of request to give more detail on this setup. The hose is a steel braided -08 Parker "Tough Cover". The centerline distance between the fittings is 15" to 15.25". I made two, and they both fit. The short one is currently in place. The fittings are 37 Deg Flared Compression...

forum.ih8mud.com

I know to use the aluminum washer 90430-A0003 on the fill and drain plugs on the t-case. My question is why? Is it due to the softness of the material? Corrosion between steel and aluminum?

When I had the hose built, they threw a washer/gasket on each end. Is it necessary to place an aluminum washer on the transfer fill plug end? If so, should I take off the one they put on that end? Here are some pics.

Thanks everyone!

 

[peesalot]

Those are fine, thats a transfer hose, correct ?, so the fitting is not seating on a nipple and the threads hold it in, in this case the threads will have oil contact so the sealing washers are good. In the case of the drain and fill plugs the compression washer prevents maring the aluminum case and to some degree it keeps the plugs from vibrating loose.