Is there any secret to getting the gear off the brake drum? I've used a three jaw puller with no success. Is this a common problem? I'd hate to use any heat because of the heat treat of the gear. My next step is taking it to a machine shop and getting it pressed off. This transmission is covered in oil so there is no rust involved.

Ford provided a "driven gear" puller - don't have the number handy but I just pulled 5 gears off yesterday checking out drums.

Did they pull pretty hard?

Fred, they cab be quite tight. I use a three legged hydraulic puller. These are strong pullers which exert plenty of force, but they pull slowly so you have good control over the operation.

You may be able to hire/borrow one.

Hope this helps.
Allan from down under.

Fred, heat won't hurt it, if its tight like they need to be then usually heat and pressure will bring them off. KGB

We used heat to get one off. I tested the hardness with a file and compared it to an original that had not been heated. The gear that had not been heated was somewhat harder according to my file test. I suggest if you must use heat, use as little as possible. We got ours nearly red hot. I suspect wear rather than strength was the design criteria and if so its unlikely you will wear out one in your lifetime.

I have a stupid newbe question, where are there gears inside the brake drum? Thanks

The driven gear is on the shaft end of the transmission brake drum.

Ed

The gear in question is the Driven Gear, its on top of the drum assemblies. Needs a puller to remove.



Driven Gear on top of drums, still in place on brake drum.....

Hello Fred:
This is a picture of the proper tool to remove the drive gear. Even with the right tool they still sometimes are a bugger coming off.

I put together a set up in my 28 ton press using 8" I-beams to get room for the drum and pressed it off. It was still tough. PK

Another puller for that gear.


Toon

Toon, that's a nice rainy day project. I made a puller to do that job yesterday. Just a scrap piece of channel iron.

Some driven gears can be difficult. My trans has a badly worn low drum gear so I got out all my drums and transmissions. I have three fully assembled trannies needing driven gear removal to allow evaluation prior to parts selection.

My puller design is stout and I immediately discovered washers were needed under the bolts (added now):

On two of my trannies the gear wouldn't budge, the channel iron started to bend! The third one came apart... not easy, however! I've decided to use that third tranny, well maybe not that brake drum (final decision later today after I apply my micrometer to the shaft).

The third set of drums were badly rusted (as found at the swap meet) so I used my lathe and handy Harbor Freight box of graduated abrasive rolls to clean them up. Rust removal and polish takes 5 minutes per drum... 15 minutes! Here is what I found:

Polished drums:



I found a casting flaw in the brake drum:



The casting flaws are about .015" deep. My decision is to use this drum if the shaft measures out. This surface void never bothered the trans in years of service as far as I can tell, and it shouldn't bother my wooden bands. I found a loose triple gear pin and everything else was nice. I suspect that the unit got noisy and "bangy" due to that triple gear so it was pulled from service... lucky for me!

I find the wear pattern on the brake drum to be interesting. The other two drums are practically factory fresh, but the brake is scored. The scoring is not where the rivets are located. If a narrow brake band was used that might be where the edge would fall except the band would be centered on the drum. I suspect that someone threw in a narrow brake band which ran cocked forwards leaving 5 gouge marks.


TH

Terry-a narrow brake band would run at the front edge of the brake drum not the rear. Can't imagine what the scores could be caused by,
Dan

Dan, thanks, you helped me figure it out. I thought maybe a non-eared ('09-'25) hogshead was used to put the band at the front of the drum. But that scoring is almost at the spot you would expect from a narrow band with the correct hogshead. I'll lay a band on it and see if it lines up.

Photo to follow.

TH

I went out to the shop and tried on bands. Since this is a driven gear thread I have decided to not continue the drift but rather just start a new thread. Click this link to leave this thread and go to the drum wear thread

TH

Ugh that sucks, my transmission just came apart with no pullers - that gear stayed under my tripple gears. Wow.


Travis
Topeka, Kansas

Terry, I think you still have a mystery with the wear pattern on that drum. If a narrow band was fitted, I think it would still run in the centre of your drum, because the pedal shaft spacings were altered with the later hogshead.

If an earlier hogshead was used with that drum and a narrow lining, it would be at the front edge of the drum as Dan said.

I can think of no logical reason for the wear as shown.

I could be wrong, again.
Allan from down under.

Allan, check the second photo in the post I linked to. I think it clearly shows how the narrow band could have caused the scoring. Terry

Travis - you'll need a press fit there, so it's either your brake drum shaft, the driven gear or both that needs to be replaced. But I think you had a cracked shaft, there's the explanation.

A big thanks to Jack Daron. Five minutes with the correct tool and it was off. Can't beat that.
Thanks
Jack

Terry, I thought that the brake pedal shaft on the 26-7 cars was moved aft so that the shaft was still centred on the wider drum. If a narrow band was fitted with that same hogshead, it would still be centred on the drum, with equal widths of the drum exposed either side of the narrow band. If I have that right, then the wear pattern should still be in the centre of the drum, regardless of which band was used.

Someone, please set me right.
Allan from down under.

You are correct, Allan, though who knows if an earlier hogshead was used? And the wear can be from the edge of the band if it was used for some time with the lining worn out.. Some people doesn't care about the sounds or signs their cars make, and back when T's were cheap worn out jalopies there were lots of that category of owners..