47-55.1 Transmission seized

[Fred n' Ethel]

Hi folks. Had been watching the lube level for years. Barely needed topping off on occasion. Anyway, just took it out for a ride and while climbing the steepest grade in the county in 2nd, started loosing power/speed, moaned and groaned to a stop. I think the clutch began slipping at the end too. Managed to pry the truck uphill a bit with a fence post to get it in neutral to drag it home. All the linkage worked fine, no gears crossed so I pulled it out. There was hardly any oil in it The one gear is seized to its shaft. The bright sunlit area was evidently hot as it is bone dry, galled I suppose. How do you get those shafts out ? There is a lot of wear throughout, are they worth rebuilding ? Any used ones available ?
Thanks,
F&E

[mr48chev]

What model of truck is it and what transmisison. It shouldn't be that hard to find a decent replacement trans and go again.

If it is a 48/51 the instructions are here http://chevy.oldcarmanualproject.com...51ctsm0701.htm

I'd carefully take it apart, photograph each step for reference and see exactly what is wrong with it. If it is just bearings that are seized up you shouldn't be in too bad of shape and can buy a bearing, small parts and gasket kit. If it takes more than that and gears or shafts are galded you may be better off finanicially to replace the trans. The $$$ add up real quick when you replace gears, shafts or syncros.

[Fred n' Ethel]

Hi, and thanks !
Sorry I left out the pertinents.

Its a Chevy, 54, 3100, bone stock, 235, 3 ONC.
I used a small brass drift and, with lube, pecked the gear back and forth and got it loose and turning. Then I saw a video of removing the 2 shafts. I see the one is pinned, but the video shows just pounding the other out towards the front. I hit it pretty hard, it moves very slightly each way but heads up solid against something ? ? ? It moves to almost flush with the forward surface, then rings solid .. like a bell. I quit for fear of busting something. How in the $%#@ does that shaft come out ? ? ? ?
Thanks again, very much !

[Fred n' Ethel]

Hi Mr48, I followed that link to my model year. Nice instructions !
I see the shaft has rotated the flat out of alignment when the bearings seized. I also noticed some blue, nearly molten metal at one of the lube holes through the counter gear right near the hot, dry section. I imagine the outer race is a mess. Might just need a bigger hammer ? Or ????? Scrap the gear and shaft, cutting torch it out ? Would save the case and other stuff.
Thanks again !

[Fred n' Ethel]

OK then ..... maybe a BFH isn't always the the best choice, but it DID answer some questions
Low oil = High maintenance

The cutting torch would have been the only other way, then more parts.
I might have another mixer here ..... somewhere.
Thanks

[mr48chev]

Well you just took care of the rebuilding using that case issue.

Allreet you chassis swappers in the West Virginia area, who's got a decent trans to donate to the cause?

[mick53]

It shouldn't be a problem finding one. A lot more people take them out then put them in.

[mr48chev]

It might be time for an open drive 55/59 rear axle and a full syncro Saginaw 3 speed.

I've got one in my 48 and even though I am putting in a 5 speed there aren't many people around who could talk me out of it.

[dsraven]

seems like the perfect time to upgrade to more speeds and possibly an overdrive, unless you are building to keep it stock. an open driveline would simplify and update things plus you could pick a gearbox and axle ratio that would help on the take off's and possibly keep engine rpm's reasonable while cruising down the highway. I understand there are likely a few of the old transmissions out there but you are still talking about an old used transmission which has seen many years of use or may need a rebuild, old used shifter mechanism, torque tube, driveline etc etc. there is always the "while I have it apart" scenario that we are all familiar with and usually ends up with a full rebuild of the old stuff and then, in the end, we still have a truck that is sorta high geared in first for taking off and tops out quickly on the highway. it may be worth the time and effort to research the costs of redoing the old compared to upgrading. I know, anything other than a 3 on the tree is gonna be more work and will end up with the shifter located on the floor, but the choice is yours. just saying to look at your options and check ALL your old parts for wear etc. I don't know what you have, how you want to build it or how you like to drive it so i am just saying look at your options and costs to do different things. a full syncro trans would certainly be a nice option.

[Fred n' Ethel]

Thanks for the tips, and suggestions. We have time to consider all.
I did have another 54 transmission. Got it a few years back from a member here. Just put it in this evening. It is in much better condition and runs much quieter than the other one. The one I busted was actually worn VERY badly. I think there was enough lube in it to prevent what happened, it was just shot. Growled pretty bad too.
I have an 84 C10, 250, 3 OTC that I was saving for maybe this 54 or the 39 Master that we have. Also have a 79 K10, 350, creeper that is rusty, otherwise OK.
Kinda like to keep the ol truck bone stock ... in a way. The 235 needs to come out and be sealed up. Runs good, just looses a lot of oil (burns a bit too).
Lot to think about. I'd like it to be dependable. But, being all stock .. ya know the steering, brakes, suspension, on and on and on......... but its cool !
Thanks again Gents,

[dsraven]

cool, back on the road. and your skill at R&R is that much better. lol.
maybe you should keep the old truck frame and driveline but then build and sneak a complete hi performance frame and driveline into the shop and have it so you can put the old truck body on either frame. best of both worlds and with your new R&R skills you could be a weekend warrior on the performance underside but then swap it back for the week days. haha.

[Jemezcrusher]

Originally Posted by mr48chev

It might be time for an open drive 55/59 rear axle and a full syncro Saginaw 3 speed.

I've got one in my 48 and even though I am putting in a 5 speed there aren't many people around who could talk me out of it.

An S10 T5 will bolt right up to the 235. All you have to do is swap out the input shaft.

[Fred n' Ethel]

That's interesting Jc.
I looked here
https://lugnutz65chevystepside.weebl...-astro-t5.html
Are you saying the input shaft is a direct swap ? Splines and all ?
Thanks

[Fred n' Ethel]

I'm wondering if the 3 spd from the 84 C10 will bolt up ?
Maybe just change the clutch disc to match the splines ?
Anyone ever do this ?
Thanks.

[Fred n' Ethel]

This is from the manuals. Mine is a 54.
The 54 illustration shows the proper clutch gear shaft with 14 and 24 needle bearings.
The 48-51 illustration shows a different shaft with only the 14 needles.
There were only 14 needles in mine, the others were consumed ? or never installed ? or it was a mix n' match mess to begin with ?
Been a lot of wrenching on these ol' buggers, eh ?

[mr48chev]

I'm going to say that somewhere along the line the 54 transmission got replaced with an earlier one. Very typical of the trip to the wrecking yard to find one that fits back in the day. It fits, it shifts and it doesn't jump out of second were about all the requirements back then. There wasn't a lot of OMG I have to get one out of a 54 because the needle bearing count is different then.

[1project2many]

3 speeds, most 4 speeds all have the same 1:1 final drive ratio. If you're looking for a way to include an overdrive the T5 is one way. Another may be to use the 3+1 A833 overdrive available in early to mid-80s GM trucks. Chrysler versions are very common but the GM versions still show up if you do a little searching. Some A833 transmissions use a unique bellhousing so you should research the possibilities for connecting the transmission to your engine if you find one with a non-standard bolt pattern. Some information can be found here: http://67-72chevytrucks.com/vboard/s...d.php?t=670789

Also note for the future: A cutoff wheel can be mounted to a 90 degree die grinder to help remove stuck or junk manual transmission gears and shafts. I'm guessing in your old transmission's case the shaft spun in the case and created a ridge on the shaft. This may have damaged the case enough so it would have been tough to use but if it was made of unobtanium you likely could have cut the shaft out.

[mr48chev]

The simple solution is to find a decent transmission preferably out of a 54 and maybe put a bearing and small parts kit in it along with new gaskets.

The next simplest solution would be to find a transmission, drive shaft and rear end out of a 55/59 3100 and swap over to open drive. You are still dealing with the older style transmission though. I'm not positive on drive shaft length.

Not quite as simple but it would make a nicer driving rig is to use a later full syncro 3 speed and the open drive 55/59 rear axle. That would take a bit of shift arm/rod tinkering and I am thinking at least a different driveshaft yoke if not a different length drive shaft. I have that transmission in my 48 with a Hurst 3 speed shifter and it is one nice transmission. NO Overdrive but smooth shifting.

Then it comes to a T-5 swap but that takes away the column shift but at the same time . That would give you smooth shifting and overdrive. Find a shift lever off an old granny 4 speed and adapt it to the shift lever and bingo the lookie loos think you have a granny 4 speed in the truck.


Still it comes down to other factors including is the rear end in the truck in really good shape now? Does the budget allow for spending the money to make the changes to open drive? That one is your personal business and no one elses. We all have different build or redo budgets and so be it and unless someone asks about specific changes Throwing out suggestions that may cost as much as some guys build budgets isn't cool.

[1project2many]

Originally Posted by mr48chev

It might be time for an open drive 55/59 rear axle and a full syncro Saginaw 3 speed.

What's actually involved in this swap? Seems like a fair amount of work and parts from what I've read.