[sixt9coug]

i went to Pomona today and picked up a 3.50 open geared 3rd member for my car. i looked it over and it looks fine and functional and all. one issue though... it is a 28 spline unit and the yoke looks right to.... BUT there is no filler plug on it. the one on my car ( and the 70s rear end i have in the garage ) has the filler plug on the pig itself. im guessing the new one i bought had it on the housing? so heres the question.. can i tap a new bung on the pig or would it be better to tap and plug the housing? or am i screwed? hope not. sure i didnt spend alot on the pig, but still. more effort sucks.

 

[droptopcat70]

Steve
i would look into having a hole drilled into the housing and have the threads tapped to match the drain plug that our cars have.Be cheaper i think n wouldnt have that ugly dot on the housing .
thanks
pat

 

[wvcat]

If it was me I would drop the carrier and the front bearing support(with pinion gear) in the old chunk. You can adjust the backlash with the side adjusters on the carrier bearings.
John
wvcat

 

[sixt9coug]

ok... i have no idea how to do that and dont intend to start the learning process here.... but ill see if my buddy can help with that. might be the easiest way. backlash is adjusted with shims right? couldnt i just swap all that over and be ok? just a thought

 

[wvcat]

you shouldn't have to shim it if the two cases are machined properly. the backlash is already set on the pinion housing/gear but when you remove the carrier there is an adjustment on the side bearings, the adjusters look kinda like big washers with holes in them. Its really not that difficult.
John

 

[Royce Peterson]

To fill it just leave one axle out, let the car down on jackstands so the side with no axle is higher than the other side. Dump the grease (2 qts) in the hole where the axle goes. Put the axle in.

I fill all my rear ends this way, it is much better than using the cheesey pump.

 

[sixt9coug]

killer made me feel better now

 

[modifiedmark]

Wait!!!!!

Hold on there dont just swap the pinion support between housings!! John you know better than that!! Thats why there are shims used between the pinion support and the housing to set the pinion depth because it seems Ford could rarely ever machine two housings the same.

By mismatching the pinion supports without resetting the pinion depth you asking for big trouble. True the back lash is easy to set but the pinion depth is the hardest to get a accurate reading on and you really need a special pinion depth setting tool to do it correctly. Belive me I have set up more than my share of rear end gears in my racing days.

Steve, your right that the early 9" rears had a plug in the housing and the easiest way to add a fill hole to the housing you have is to drill a hole in the back of the housing at the same level as the original plug in the pig and then mig weld a shortend pipe plug in the hole in the housing as the housings pretty thin to be tapping threads in. Use a nice hex headed brass pipe plug in it and your ready to go. I'm sure that at school you have access to a mig welder for a 10 minute job. Personally I wouldnt want to have to pull an axle to add gear lube to my rear in case of a pinion seal leak or such. mm

 

[sixt9coug]

so Mark, you reccomend adding the hole to the housing itself rather than to the pig?

 

[modifiedmark]

I guess it depends on your ability, tool availbility and wishes. If your comfortable drilling and tapping the pig, fine if you have the correct sized drills and taps. But if you dont and have access to a welder than doing the houseing is cheaper,faster, easier to do and it is more accesable in the back of the housing. If a man wanted to while the pig is out you could also weld one in the top of the housing for even easier filling, and also one in the bottem for easy draining. Ok I got carried away but you get my point. mm

 

[Royce Peterson]

Seems to me you have to have the axles out to change the center section so there would be zero work involved.

 

[modifiedmark]

Royce, you never had a rear end leak?? The guy uses his car for his only means of transportation. Maybe a leak develops out of the pinion seal and he has school and work to take care of before he can get into changing the pinion seal on the next weekend? Now to keep the rearend full he now has to pull and axle?? I dont think so. A 10 minute job while the pig is out is all it takes to put the fill plug in so in my mind it would be crazy not to especially as its not a concourse show car where the orignality would be affected.

I'm also surprised you didnt mention about changing the pinion supports between cases as a no no. mm

 

[70XR7ConvertCat]

I have a chronic leak out of my left rear axle seal. Not much, but enough to leave a couple of drops of lube wherever I'm parked. The seal was replaced at least once before for leaking. This car doesn't get driven much, so I'm speculating that the left axle may be just slightly bent, enough to wear the seal enough over time to cause the leak. I may have 1500 miles on it from when I last replaced it, but that equates to ~3 years. The bearing seems to be ok. Does anyone have an informed opinion on this, or would care to otherwise speculate?

 

[greggieatthebat]

70XR7ConvertCat-
I care to speculate about one thing - check your brakes! My '68 has (apparently) a leaking axle seal on the passenger-side rear; I pulled the brake drum and my entire setup is well-oiled! Great for moving parts, not great for moving parts designed to use FRICTION to STOP my car! My leak never left evidence on the ground either, but the backside of the wheel is gunky.

 

[jimk351c]

Would it be possible for Steve, if he was in a pinch with a leaky seal, to add grease through the vent tube?

 

[modifiedmark]

I have a chronic leak out of my left rear axle seal. Not much, but enough to leave a couple of drops of lube wherever I'm parked. The seal was replaced at least once before for leaking. This car doesn't get driven much, so I'm speculating that the left axle may be just slightly bent, enough to wear the seal enough over time to cause the leak. I may have 1500 miles on it from when I last replaced it, but that equates to ~3 years. The bearing seems to be ok. Does anyone have an informed opinion on this, or would care to otherwise speculate?

I would think that an axle bent bad enough to do that would cause a noticeable vibration in the car. When you pull it the next time to fix it make sure the axle bearing isnt worn and loose and double check the surface of the axle where the seal rides against it to make sure its smooth and dosent have a grove wore in it.

That being said if all is well it is possiable to damage a new seal when installing it and may have been the case. If driven in improperly or if the sealing lip is nicked when the axle is installed they wont hold a leak proof seal very long. You want to make sure and oil the lip of the new seal when installing it also.

jimk351c, yes it is possiable to fill through the vent tube fitting. Not a very good way to do it though as that fitting has a maybe 1/4" hole in it and no way for air to escape while trying to force 90wt gear oil through it!! Why not just put a fill plug in it?????mm

 

[swamper]

This was an existing problem on my car when I got it (No way to fill the rear). The local shop suggested drilling and puting in Dodge rubber plug. They had one in one of their cars that didn't look bad. I bought an other pumpkin in stead that had filler plug and was setup with trac loc.

They also said casing is too thin to tap directly.

 

[drShelby]

Hey 69C,

Looks like there are several good options mentioned here. If the 3rd member case is out of the housing, drilling and tapping the case isn't difficult at all. To control metal shaving debris you might try securing the case on it's side and drilling from underneath taking care that when you have almost drilled all the way through that you proceed slowly to not press through to the pinion (can't remember if the ford fill plug location is horizontally in line with the pinion or not, you can eye it to quickly see what's behind where you are drilling). I don't have any stock housings with factory plugs on them. The rears that I have modified required drilling a hole and welding a pipe threaded bushing on the housing for the plug to thread into. Swapping the gearset can be time consuming as well.

Drilling and taping is a much quicker solution (If you run short on time - Royce's way wins on being the quickest).

Let us know how it turns out.

 

[70XR7ConvertCat]

Greg,

Yes, my brake shoes are ok. It (currently) doesn't leak enough to sling onto the brake mechanism. The last time this seal failed I was driving westbound 80 toward San Francisco. A warm summer night with the top down. Anyway, it made it home, but the brake was ruined. Everytime I touched the brake pedal a god awful cloud of smoke would pour off the wheel. This problem just irks me because I hate to have to replace an axle, but I don't know what else it could be at this point.

Steve C.

 

[70XR7ConvertCat]

modifiedmark,

By the way, it's a good observation on your part about a vibration. It does have one at a certain speed or rpm combination, which is one of the reasons I suspect the axle is bent. When it occurs, it sounds as if the license plate bracket shudders, but who knows what it is?

I can't remember if I replaced the bearing on this axle at the same time I replaced the seal. I may have. I do seem to recall replacing the seal for the other axle at the same time, eventhough it was fine. Still is.

I'm awaiting my new data plate from Marti Autoworks now the car is painted. I asked Kevin to use the rear axle code for a traction loc, so you can see what the future holds. The open differential will be replaced with a Pro Series Auburn limited-slip, so this is when I'll deal with the axle seal again. Do you have any opinions on aftermarket axle sources, such as Dutchman's?

Steve C.