Third gear not working - found this in tranny

[WilsBoar]

So, third gear was not working, took it apart and look what we found in the bottom of the tranny.

Probably not good eh? Does it make more sense (cost) to fix this tranny or find another to drop in. Preferably something fully synchro'd.

What do you all think?

Derek

[o2batsea]

Year?

[I Leak Oil]

Well, they're easy enough to rebuild. The risk you take putting in another used one is you may have the same issue or worse unless you know for sure it's good. That is the hard part with used units. I'd rebuild.

[rdsrover]

I would re-build or replace with brand new. It's hard to imagine a transmission being the only good thing left on a scrapped vehicle.

[WilsBoar]

Its my 1969 109. I would rather rebuild than inherit someone else's issue. What is this part anyway? I am looking at the schematic and it looks like several parts. What is a rebuild going to cost me if I pull it out of truck myself?

[WilsBoar]

Ileakoil, have your ever rebuilt one of these? I am game for trying, especially if you feel it isn't terribly difficult. Its already almost out of the truck anyway.

[Momo]

These gearboxes are really simple. Basically you have the shift fork assemblies and the gearsets and some bearings and that's it. You could rebuild it in a few hours on the garage floor. Take it apart and inspect everything for wear, order what you need, and put it back together. Take some photos along the way for reference and ask some questions here when you get stuck.

[I Leak Oil]

I've rebuilt a couple for my own use. Really isn't a bad job at all if you're mechcanically inclined, and more importanty, willing.

[WilsBoar]

Anyone have an idea what this chewed up part is and if there should be some additional pieces in my tranny sump?

[westcoastkevin]

I have an earlier gearbox that might have some differences but it looks a bit like the remains of the rear layshaft bearing.

What diameter are the roller looking things?
Approximately what diameter is the ring?
Are the ring segments steel or bronze?

The rebuild is not hard but you will need to get some puller sets to get it stripped. You may need access to a hydraulic press too. Keep all of your old bearings. You might need the races for driving in the new ones. You will need some brass drifts too.

Kevin

[WilsBoar]

It may be the rear layshaft bearing judging from some online pictures. If so, there are some random parts still floating around that may be the culprits for jamming up my 3rd gear...at least.

[I Leak Oil]

That's a possibility. That bearing is small compared to most of the other bearings in it. I was just looking at an old set of bearings I have. The part you pictured could also be bits of the roller bearing between the primary input and the main shaft. That's also where the 3rd/4th syncro is so that could be causing your shifting issue.
Judging by the size of the rollers in the picture, it's most likely the layshaft bearing though.

[WilsBoar]

Thanks. I guess it is a certain rebuild. What should I expect to pay for a rebuild?

[Max(SD)]

I am doing a rebuild on a SII gearbox, I have removed everything. I am replacing two gears, all the bearings, one layshaft, all the rubber seals and all the gaskets. I have had all the various gearbox and transfer casings washed and cleaned, I am also replacing the u-joints on the front and rear prop shafts. Since everything is apart I have sent some parts for powder coating, new clutch, some new nuts and bolts, and refinishing the old nuts and bolts. This is probably going over board, but I figure everything should come in slightly under $800. I took gearbox apart in pieces, but I will probably put everything back in one piece and have to rent some type of lift to put back in the truck. But I don't seem to be moving very fast, as life is constantly moving around me, and I might get a couple of hours here and there to concentrate on the truck.

Take lots of notes, take lots of pictures. Taking things apart is easier than putting them back together, especially taking dirty oily things apart are look different when things are clean and new. When I took the transmission brake assembly hardware apart, I did not take too many pics, and I regret that, will probably come back to this site for help, as I got all the pieces powder coated, will certainly need assistance putting it back together.

Best of luck.

[I Leak Oil]

Thanks. I guess it is a certain rebuild. What should I expect to pay for a rebuild?

Depends on what needs replacing. At a minimum I'd replace all the bearings, bushings, seals and synchro. Gears for first and reverse are common to have to replace.
Your labor is free, if you have to pay someone it's probably best to buy an already rebuilt unit.