[KA24Ewoog]

my old 88 SE V6 (VG30) has had a seized 'fill plug' on the rear end since I've had the truck. I've tried heating and cooling it, PB blaster, hammers, you name it and nothing has worked so far to remove it. It's rounded out in the inside (where you'd use your ratchet to get it turn it loose) and I'm assuming the previous owner probably used an air wrench to put it back after a gear oil change but I have no idea. It was rounded when I first looked under there a couple years ago.
ANYWAY, while under there taking a look at it, I noticed a little fitting thing on the differential housing itself, on top, on the driver's side....it has a little metal cover that comes off but has a spring and clear plastic disk inside of it. It looks like the fitting on the diff housing that this thing covers, is open and goes down into the differential housing but I couldn't get my head up high enough to look into it.
Anyone know what this is? I can't get the fill plug out and the truck has 210K on it so who knows how long that gear oil has been in the rear end. I'm debating on getting another rear end or figuring out another way to get that plug out. I could add oil thru that little fitting on top but would have no way to know what the level is.
No diff housing cover or bolts or other access into the differential.
Thanks guys any help appreciated!
cheers:givebeer:

also forgot to add: 2WD, 5-speed

 

[dvdswanson]

pull the 3rd member and drill and tap the filler plug and install a new one. or buy an axle from a j/y.

 

[rogoman]

That top vent with a cover on it is a breather vent; keeps the differential case from developing too much pressure.

 

[KA24Ewoog]

That top vent with a cover on it is a breather vent; keeps the differential case from developing too much pressure.

AH that makes sense...exactly what it looks like.
Thanks!

 

[imperium]

got access to a welder?
you could weld a socket into the hole then force it out
no guarantees if it will work but it should

 

[1989D21]

got access to a welder?
you could weld a socket into the hole then force it out
no guarantees if it will work but it should

I had a shop do this to my trans drain plug, except he welded a bolt to the plug and used his air ratchet to remove it. Worked great!

 

[iggy03]

the top vent on the rear dif

That top vent with a cover on it is a breather vent; keeps the differential case from developing too much pressure.

Hi I took my 94 HB in to the shop today for a tune up and they want to re direct the rear dif vent elswhere near the rear of the truck or fender well... Is this nessisary ? Should I go forward with this repair ? Or is it something a "non" Mechanic coulod do ?

Thanks

Iggy

 

[Spinlock]

Hi I took my 94 HB in to the shop today for a tune up and they want to re direct the rear dif vent elswhere near the rear of the truck or fender well... Is this nessisary ? Should I go forward with this repair ? Or is it something a "non" Mechanic coulod do ?

Thanks

Iggy

Sounds like they're trying to take you for a ride. What reason can they give?

 

[iggy03]

Sounds like they're trying to take you for a ride. What reason can they give?

The reason is that.. the vent is clogged and by re directing the vent away from (where it is) this will prevent future clogging / plugging.

 

[Spinlock]

The reason is that.. the vent is clogged and by re directing the vent away from (where it is) this will prevent future clogging / plugging.

My guess is, it's clogged because it's a 22 year old truck, not because of the location of the vent.