The Stovebolt Site Forums The Shop Area Engine Shop What type transmission to buy?

I am looking into replacing the transmission on my 1953 GMC truck....what would be a good transmisssion to look at? My motor is a 228 inline 6 and i recently found out that the original transmission was removed and I am unsure what type is in it now..all i know is that i cannot figure out what type driveshaft should be in it to match the replaced transmission....when i replace the transmission, will i need to buy new driveshaft, and rearend too to go with it?

Why replace the transmission in it now?

The answer to what the replacement should be really depends on what you are trying to accomplish.

What model truck is this?

because the transmission is locked up, i do not have the correct drivshaft or rearend for the one in there now...and am looking to replace entire package because of finding parts constraint.....i want a tranny that will give me 55 mph on highway and thats about it...nothing special..just good driving capabilities....three speed or four speed...makes no difference to me....have been advised a Saginaw trans would be a good choice...what do you all think

its a 1953 GMC truck with a 228 engine

How do you figure the tranny is locked. A few days ago you were asking how to tell if the engine was locked up. You never responded to the people who advised you on that.

Transmissions rarely lock up unless someone has managed to jam it into 2 gear positions at once.

Also, if your 5 speed is a Clark with OD it is a desirable tranny. You should find out what you have before deciding it needs replaced because you don't know what kind of driveshaft to connect to it.

53GMC,
You still need to list what model your truck is, if you
want soemone to answer your questions properly.

A '53 GMC with a 228 could be any of several series of trucks. Knowing which series would help a lot because the stock driveshaft configuration varies depending on the model.

I say that the tranny is locked up because the shifter will not move...

I am extremely sorry for not responding about the motor lock-up question Cletis. I am a fully enrolled college student, working his way through college, trying to make a living and do not have much free time to respond. But I appreciate your help anyway Cletis.

OldSub and Ghost Rider...I didnt realize that it could be any of several series. It is a first series. I hope that is the information you are looking for. Thank you for your help.

And I am sorry for my questions not being fully detailed about what type of transmission and motor are in it because I am new to working on older cars and have only restored late 30's and 40's tractors in the past. As it is I had to ask many questions in my learning years of tractors, now i am more intelligent about it. That's all these questions are - learning.

But thank you all for your help.

College is a good thing, and often needs to be treated as a priority. So far I've paid for four degrees and may have numbers five and six still to deal with. I only did the course work myself for my own two degrees.

I expected to hear that its a 100, a 150, a 250, 280, 350, 450, something like that. The serial number would answer the question if numbers on the hood do not.

1st Series usually means a '55 Chevrolet, and strictly speaking does not identifiy any GMC. Having said that, if you look at my signature line I identify two of my GMC's as '55 1st. What that means is the trucks were both made after the change over from '54 models to '55, but before the change to the later body style. Chevrolet makes that distinction. I make that distinction. GMC did not, and GMC purist all think I'm confused.

The series or model information I'm asking for tells us what load rating range the truck was built for. The serial number found on the plate in the driver's door opening will clear it up.

A '53 100 (1/2-ton) will have a torque tube.
A '53 150 (3/4-ton) will have ?
A '53 250 will have a two-piece open drive shaft.

I've seen 3/4-tons with partial torque tube, partial open drive shaft. I know after '54, all the trucks were completely open, but in 3/4-tons it might have happened earlier, and it did in 1-tons.

Someone who knows 3/4-ton trucks better than I can jump in and clear that up. I've only owned 1 3/4-ton ever (ignoring the modern one I have now), and it was a '47. It had half torque tube and half open.

Anything bigger than a 250 will have a multi-piece open drive shaft.

Just for sake of example I'm going to assume you have a 1/2-ton truck, which will be a 100-series. 100 on the hood and a model number in the low 100's.

My '55 1st GMC Suburban is a 1/2-ton truck with the GMC 270 motor, an original type 4-speed and a later rear axle with 3.08 gears. I can run 75 on the freeway with out straining the motor and its quite comfortable at 55.

There is more than one Saginaw transmission out there. The one often swapped into these trucks is a car type 4-speed. Its going to drive like a car and have the same 1 to 1 final ratio as the truck transmission I have. Choosing your rear gears and transmission need to be done so they compliment each other.

Another popular choice is a T-5 5-speed, which provides an overdrive in 5th and means gears closer to 4 to 1 might make good sense in the rear.

I hope this additional info helps you answer our questions so we can do better pointing you in the right direction.

That is an EXCELLENT answer to the newbie's question OldSub.
Hats Off to you.

Thanks Dave. Sometimes I make the effort to be helpful... Other times...

Ok, time for my experience on this tranny lock up problem. Had the exact same symptoms on my '54 Chevy 1/2 ton, 3sp on the column. When we took the truck off of the trailer we put it in gear and the truck must have rolled a little, putting pressure on the internal components of the transmission. A week of inspecting things and trying to work the gear shift out of gear had no results. So, Alvin(Achipmunk as he is known here) suggested that I jack up the rear end of the truck, set it on jack stands(so that it doesn't fall, and chock the wheels. With that done, either turn over the engine with the starter or turn it over by hand using the crankshaft pulley on the engine. In 10 minutes after getting the rear end off the ground my truck would go into all 4 gears with no problem. If you're engine isn't stuck, this should work to figure out if it is really locked up or not. If your engine is locked up, you'll need to remove the spark plugs, get some diesel fuel or Marvel Mystery Oil, maybe even some PB Blaster, pour some into all cylinders, let it set for a week or so, and then crawl underneath the truck, remove the flywheel cover, and gently pry on the flywheel teeth with about a 12" flat pry bar. After about a week of setting I barely had to push on the bar to turn the engine over. That's how I did mine anyway. Also, it will be a good idea to change the oil because it probably needs changed from setting and some of the stuff you put in the cylinders to free up the engine may have seeped past the rings into the oil pan. All of the necessary materials only cost $20, compared to who knows how much you'll spend on a new engine or transmission if you end up changing them out. I hope this works for you if you try it. I'm 14 and got it done so just about anyone should be able to.

Dang! That really helps me Old Sub and jdl!!! a great deal!

OldSub, It is a 1/2 ton truck so im assuming that means a 100. I didnt know that GMC's did that type of numbering because my decals on the hood are missing. I knew Chevy had the 3100 but know i understand what you mean. I REALLY APPRECIATE the detailed information from everyone that responded...it may take a little while to sink into my head but thank you so much for all of it!! And what doesnt sink in immediately will be there for me to refer back to later!

I will look into the gear ratios of potential future rear ends and trannys for my truck! Thank you because now i have a better idea of what to be looking for and i wont be searching scrap yards aimlessly! Ive heard of the T-5 trannys and all good so i will likely look into those some!

jdl, I'll take your advice as I have had a few others say to perform the same type procedure and I will give it a go. I believe that will do the trick myself!

Thank you all again so much!