Transfer Case Speedo Double Seal Writeup / How To

[F-junker]

Looks like I've found another little project for this winter! thanks for the write up.
The mill that your using above (Pinhead) has the cutting surface to the same tolerance of the shank? Was this bit an Ebay thing as discribed above? Do you have a good source for those mills?

Thanks a million Ken

 

[Pin_Head]

The mill that your using above (Pinhead) has the cutting surface to the same tolerance of the shank? Was this bit an Ebay thing as discribed above? Do you have a good source for those mills?

Yes, the mill has a cutting head the same diameter as the shank (+/- .001). This allows you to use the smooth shank to pilot the mill in the old seal hole so that you can't cut too deep or out of round. I got the mill at a gub show. Ebay has similar items. It doesn't matter much whether the cutter is single or double cut; it will still do a job on cast iron.

 

[1973Guppie]

Ken, there's a link above where you can buy one similar or just search around and they are out there, like I said I found a rasp like one that should work fine on ebay, search for rotary file or rotary rasp....

 

[1973Guppie]

a little frustrated here and now I feel like an ASSHAT.

Took the 40 for a nice long drive tonight, got back home and noticed it is still leaking, fresh new gear oil from the back of the ebrake plate behind the drum.

So, need some help, what did I do wrong?? Is it probably what Dgangle said above and that I didn't set the bearing preload correctly? I will do some reading here to see what it might be but if anyone has any ideas they would be appreciated.

I can't believe I got to tear it apart again. When it rains it pours, this truck is killing me lately. clutch master, then brake master, then booster, then the TC leaks, oh yeah and when I was driving it my brights switch busted on me.

wow.

 

[Pin_Head]

Just removing and replacing the bearing retainer isn't going to change the preload, as long as you put the same shims back where you found them. Is the speedo drive leaking past the O ring?

 

[Poser]

Before you tear anything apart again:

Chock the wheels, put the truck in neutral and release the parking brake.


Get under it and grab the parking brake drum and try and move it up and down, side to side, like you would try and check for a bad pinion bearing or other bad bearing on a power shaft.

If there is any movement, either the nut is loose on the parking brake drum retaining the drum to the transfer case main shaft, or, you have bearings that do not have proper pre-load on them, which is allowing the main shaft and consequently the parking brake drum to run out of a concentric rotation, and wobble, allowing oil past the seals.

 

[1973Guppie]

pinhead, I checked the speedo oring and it looked ok, I don't see oil coming from there, it is coming from the back of the drum backing plate, I put back the shims in the same order, thanks for your help

poser, I torqued the nut down to 120pnds per the fsm specs, will do as you reccomend tomm and report back, thanks....

 

[dgangle]

Take a close look at the PB drum and try to find exactly where it is leaking.

Did you put any sealer on the output shaft splines? It may be leaking there. To find out you will have to drop the DS at the PB drum. It will be wet around the nut. But you did say it was wet down the back of the backing plate. That tells me it is a seal issue.

Regarding the shims behind the speeedo housing that sets the output bearing preload, just because you put it back the way it came out doesn't mean it's correct. Feel for play/movement in the drum like Steve says and dimes to dollars the source is one of the two.

To set it, just follow the steps in the FSM. You will have to buy shims of varying thicknesses for this from Toy. I bought an assortment and then I had whatever was needed. Pretty inexpensive too as I remember.

 

[1973Guppie]

Ok, so I went out and did exactly as Poser said, chocked wheels, neutral, parking off, got under there and yanked the drum back and forth and side to side, NO MOVEMENT AT ALL. Seriously, none, seems very tight to me??

Is it necessary to put sealer on the output shaft splines?? Thinking logically I woudl think the ebrake drum splines would seal most if not all of the gear oil from coming past it? Is it possible the splines are worn enough that fluid is coming past them. FYI, I did not put any sealer on the splines at all, I put them on dry. Is there supposed to be a gasket between the ebrake backing plate and the speedo housing? I put this together dry as well, seems it will be illogical to put a seal there as if the speedo housing seals were doing their job it would be unecessary.


HELP!

 

[Poser]

Oil leaking down the splines of the output shaft would not leak out at the backing plate area as you have described. I typically do not put any sealant on the spline area of any companion flange or parking brake, unless I took it apart and it was that way previous.


Did you put any grease/oil on the seals before you installed the parking brake drum on the shaft and slid it through your new seals?


I do not see where you noted that you did that, or a picture of the seals lubricated.


Also, is it possible that the seals are riding between the area where the wear sleeve starts and stops, creating an uneven wear surface?

 

[1973Guppie]

Hey Steve, yes I greased the parking brake drum shaft as well as put some grease on the speedo seals, not a ton but enough to keep them from burning up I think, used all purpose grease.

not sure what you mean on the wear surface, I would think that the seals would compensate and flex to accomodate that speedi sleeve thickness?

hopefully when I pull it back apart I will be able to see where it is leaking from better.......I will take some pics and post up later.

Noah

 

[Poser]

I would drive it some more so that you might be able to see where the seals are riding/wearing on the sealing surface of the parking brake drum.

 

[1973Guppie]

Ok, will do, it may be awhile till I feel like taking it back apart. I wonder if it is better to NOT use the speedit sleeve and just use the double seal??

 

[bigassbike]

Ok, will do, it may be awhile till I feel like taking it back apart. I wonder if it is better to NOT use the speedit sleeve and just use the double seal??

I was just going to suggest that, seems like it would be woth a try.

 

[DomSmith]

Noah-

Not sure w/o seeing pictures of your leak, but is it possible the gear oil is seaping from the bolts holding the retainer? I am struggling with this right now. Need to get off my ass. Mine was all over the place after driving and took a while to pinpoint the leak. It originally looked like a leak from the seal area but in reality it was leaking onto the back plate rather than from it. May not be your problem but thought I would throw it out there...

 

[1973Guppie]

OK, so I pulled it apart and the only thing I could figure out is that the speedi sleeve was not riding on the correct part of the seal. It seemed to be riding on the back of the 2nd seal. So, I used a chisel to move the speedi sleeve down the shaft a bit more so that it would run exactly where it should be sitting on the stock seal location.

Drove it today, and the bitch still leaks! I am sorta at the end of my rope here, can't figure out what I have done wrong. I am thinking of either pulling the drum and cutting off the speedi sleeve to see if the speedi sleeve is causing a leak OR pulling the drum and putting on like 3 speedi sleeves on the drum brake shaft? I know I got the speedi sleeve to ride on the outboard stock seal so I am unsure of why it is still leaking? I have tested for slop in the output shaft (per poser's instructions) and there is none, it seems tight.

Is it possible that the drum brake shaft is so old that it has worn down to the point that it is not sealing at all?

I am filling the TC where the cruiser is sitting on a decline (snout down), so it may be getting a bit overfilled, would this cause any problems??

any chance that the shims are bad (flattened) and need to be replaced??

Any ideas??

Noah

 

[crusier72]

I ran into a problem with getting the wrong seals do you have the numbers off the seals. What year is you're tcase?

 

[1973Guppie]

spector p# 068-15A

90311-45001

I told spector it is for a 73 fj40, I have the stock TC that came with the truck.

edit: the above is off of the sticker that sor put on there, there is a small # on the rubber part of the seal: AD2651E

Noah

 

[TLCObsession]

spector p# 068-15A

90311-45001

I told spector it is for a 73 fj40, I have the stock TC that came with the truck.

edit: the above is off of the sticker that sor put on there, there is a small # on the rubber part of the seal: AD2651E

Noah

There are 2 different Tcase brake shaft diameters, with 2 different corresponding seal diameters. I would get out a claiper and measure it and make sure you have the right seal combo.

Also - I always used sealant on the back of the big washer in order to seal the splines. Its usually only a problem when parked uphill or if the TC is overfilled.

If the preload is wrong, you can start to have symptoms similar to a bad u-joint - but mine did not leak.

Jim

 

[67azcruizr]

The inside lip that you ground down to fit the two seals would hardly be considered "machined". Even on machined seal seats, I run a smoothed out bead of Permatex ultra on the O.D. of the seal. It is not out of the ordinary for a seal to leak between the seat and not on the seal itself.

hope this helps, sounds like you tried everything else