Replacing the seal/s on a ZF E-brake assembly????

[Fordman75]

I tried posting this on the "medium duty truck" forum here but didn't get any replies.

I was laying under my 91 F-Super Duty working on the starter and I noticed there was a leak at the back of the transmission. It looks like it's coming out of the E-brake drum.

The truck has just been sitting for the last year and a half. Next month I'm going to be fixing the fuel system to get it road worthy. And I want to fix the leak on the E-brake assembly. I'm hoping the unit isn't toast. I can't afford to replace the unit. So I'm hoping I can fix the leak.

Anyone have any experience with replacing the seal/s on this unit? Any tips? Maybe a break down diagram of the unit? I'd like to know how deep the crap is before I get into it!

And is this easier to do with the trans in the truck or should I pull the trans and do it on a work bench?

Thanks for the help!

 

[94f450sd]

no need to pull the tranny.it just bolts on like a transfer case.i believe 6 bolts.itll slide right off.somewhere here i believe is a post by me with all the part numbers.but IIRC its not rebuildable,or atleast it wasnt when i messed with mine.i did mine twice and screwed it up both times.found a new one on ebay for 600.00.

 

[Fordman75]

Thanks for the info.

I can't afford to replace the unit. So If I can't fix it then I'll need to dump it. I can swap transmissions for less money then that unit cost.

 

[94f450sd]

you wont have a parking brake if you get rid of it.and youll need a custom driveshaft or ujoint.

it can be rebuilt.but you cant seperate the drum,yoke and spindle as it is assembled and balanced as a unit.

 

[Fordman75]

The stock E-brake assembly doesn't do me much good if I can't drive the truck because of it. If I removed it I would come up with a unit off another vehicle and just adapt it to work. Or make up my own. The driveshaft doesn't bother me because I'll need custom shafts anyways when I can hunt down a cheap brownie aux. trans.

All I would be doing is replacing seals, bearings and possibly the shoes(if they are bad ) . Can the shoes be changed without separating the drum/yoke/spindle assembly? And if you did have to separate them, couldn't you just mark everything and reassemble it the way it was. Like keeping a drive shaft in phase? I've never worked on one of these units before so I don't know. I've just been reading about a lot of these units with seal leaks. And if you run them dry they can seize up. So I want to take care of the leak. If I can't fix it then I'll need to figure something else out.


Thanks for all the info.

 

[94f450sd]

ive done it twice.according to ford its not user servicable.its been a few years since i messed with one.

 

[Fordman75]

I've rebuilt engines transmissions, differentials and just about everything else dealing with gas trucks and cars. I'm just a little bit of a newbie when it comes to the diesel stuff.

I'm hoping I can handle it.

After a bunch of searching I found a place that has the breakdown diagram and they sell the parts for them. They sell a bearing & seal kit for them. It looks like I can get the bearings/seals and shoes for around $150.00.

http://www.allstategear.com/BRAKEHOUSING.htm

It doesn't look too complicated ( how's that for a kiss of death! ) . That spindle sure looks a lot like a 4wd truck front spindle.

After studying the diagram a little it looks like if you pull the whole assembly off the transmission. You break the large nut loose, remove the spindle/yoke/drum assembly from the housing ( might need to press the spindle out ) . Once the spindle assembly is out of the way, the shoe assembly can be unbolted from the housing.


It "looks" pretty straight forward. I'm going to tackle my fuel system rebuild and then I think I'll try to rebuild the E-brake assembly.

 

[tknomaj]

That whole Assy. Comes off. and is repairable . If You remove the whole drum assy the transmission is the same as a 4x4 trans and transfercase will bolt right on. So take it off and repair it just do not let it scare you it is a drum brake just as in rear with just the cable as accuator.

 

[Fordman75]

Cool, I'll pull it and give it shot. Now that I've seen what it actually looks like on the inside I don't think I'll have a problem repairing it.

But worse comes to worse I'll slap a NP205 in it's place and fabricate a driveline brake on it. Then I'd have low range to go with my 5.13 gears just in case I ever need yank the earth off it's axis or anything.