We pulled the rear portals off the destructo mog to put on the Defender 110" narrowed mog housings and look what we found? Its a metal tube with rubber "seals" on either end that slips over the axle shaft. What the heck are these for? Talked to a mog parts dude and he was stumped.

Billster

We pulled the rear portals off the destructo mog to put on the Defender 110" narrowed mog housings and look what we found? Its a metal tube with rubber "seals" on either end that slips over the axle shaft. What the heck are these for? Talked to a mog parts dude and he was stumped.

Billster


Those MIGHT be part of a pressurization system for a "fording option". The newer 435's (U1300) have a system that runs the axles at positive pressure to keep water out in deep fording. It's possible the original mil customer for those axles specified this kind of option. The tube *MIGHT* allow this same positive pressure into the portal boxes.

And, I MIGHT not know what the f**k I'm talking about...I suggest posting the question on the TX4X4 Mog list - many true 404 experts there - much more then here...

Do you know what kind of 404 the axles came off of (Swiss, French, ect) ??

Mine had the same set-up...also had the front portal vent tubes that connect into the knuckles and then to the main diff housing. The way the rubber seals on the ends of the tubes are set up, it seals on the upper bearing retainer in the portal and then on the flange inside the diff housing just before the 3rd member. The only thing I could come up with was that they were there to keep oil out of the axle tubes themselves, which would make sense because when your truck is off camber the gear oil would flow to the down hill side and the large lip in the housing would trap the oil in the tube even when the truck was level again and possibly starve the ring and pinion. That was all I could come up with...I stared at them for a LONG time when I put my diffs back together. If that is what they are for, why wouldn't all 404s have them and why are they only on the rear?

My rear had that also. I narrowed that tube to match when I narrowed my housing. I figured that it was for gear lube issues, but like stated above, why doesnt the front have them??

All 404/401 rear´s have this tubing. The front´s have the seal on the shaft!