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Author Topic:   3 speed manual specs...?
ssaamm
Member
posted September 28, 2003 05:42 AM
Ok, I'm making that big switch from junk transmission to a manual. I have an old 3 speed out of a 1960 GMC pickup it says T-24 on it. How, and where do I get info on this tranny such as gear ratios, clutch to use, so on and so forth?
I am completely dumb to manuals, I already added the clutch pedal, and linkage to the car, changed the steel bell housing to an aluminum one, and got a new rubber mount but I have no idea where to start when it comes to putting the starter on, clutch, T/O bearing, I don't even know how much fluid or what type to put in the darn thing...lol...
Any help would be most appreciated.
Great site, and great bunch of fellas too B.T.W.


rico 08
Member
posted September 28, 2003 08:18 AM
Try not to get too old of a tranny,alot of that stuff is worn out,but my old three speed was old as dirt and never gave me any problems.I'd run the block mounted starter,you can run the bellhousing type if that's what your referring to but i've never tried it.The biggest thing to watch out for is those older type trannies had long style throwout bearings and if you put them onto a later style pressure plate it will not let the clutch release.Use the 10.5 clutch and flywheel i'm sure you can find a clutch flywheel t/o bearing on here.There are two plugs on the side,take both out and put 80-90 wt gear lube in the top hole till it comes out the bottom one and she's full.


pit_boss
Member
posted September 28, 2003 11:01 AM
as far as I know the input shaft on 3 sp trannys tell the story, for example if you have 1 that has no lines on it,the ratios would be, 1st gear 2.85, 2nd 1.68 and 3rd 1.00. you said you replaced the steel bellhousing with an alminum one,unless you wrote it wrong, I would suggest for your own saftey to use the steel bellhousing. Jim


ssaamm
Member
posted September 28, 2003 02:24 PM
I'll check on the lines... I did switch to aluminun, the reaason was the shape. The steel one is very strangely shaped, and I thought I'd run into starter problems with it because it was made for a bell house mounted starter. Can I use this bell house with a block mounted starter? I agree steel is better and I would rather use it but I was just trying to save a head ache when I go to button it all together.
Thanks a lot guys, I already feel I know more.


dgb
Member
posted September 29, 2003 12:21 AM
Well, it is a stock steel bell housing for the pickup, I will take your advice and keep the alum. one then. I will have either 5.20, or 5.56 gears, run in 3rd gear with 235/60/15's, I will probably get mopped very baddly, most people there use 5.56, or lower with a lot more H.P. than I have, but I figure I can atleast try the manual trans to try to keep up in the top 6 or 7 instead of dead last. I have no idea how this will work it self out, so any help, any at all, I would be very greatful. if it helps and/or sparks any ideas, I am running a 78 Monte Carlo, 355, the 3 spd. we spoke about, and the stock rear end housing.
All on a 1/4 mile track banked maybe 10.
Again, thanks a lot guys.


tilley88
Member
posted September 30, 2003 01:08 AM
As far as I can tell, you fella's are talkin about the old "potbelly" Saginaw 3-speed. These trannies have a 1.75 or 1.57 second gear. As long as you use the one with the thicker input shaft, they'll hold up. If you use the one that necks down on the input shaft you'll have breakage.


ssaamm
Member
posted September 30, 2003 08:11 AM
Thanks tilley88, How do I know for sure though that this trans. is the one that came in this pickup? anyone know that? I thought about that at work. I took the tranny out when I was restoring a 64 chevy pickup. The 64 chevy had a 700R4 in it and we all know that wasn't from the factory...lol
So that lead me on a mind journey... what on the 60 GMC that I know for sure wasn't original. I came up with a lot, rear end, motor, cab, bed...the list goes on.
Is there a for sure whay to know exactly what I have?
I still havent had a chance to look at the input shaft for lines, will this tell me no matter what, or will the older ones not have the lines?
Thanks guys, sorry to be so much trouble!


tilley88
Member
posted September 30, 2003 11:26 AM
They don't have any lines on the input shaft, and they only have 4 0r 5 side cover bolts. I'll get back with ya on that one, tho. I'll try to get a pic posted soon.


c21
Member
posted September 30, 2003 11:33 AM
They made the potbelly all the way up to '68 and went as far as puttin 'em in 2 ton bobtrucks. I've seen 'em hold up well in heavy streeters runnin 406's. Just stay away from the one's with necked down input shafts. They are hard to find, too.


racer17j
Member
posted September 30, 2003 08:17 PM
you might want to look into another gear also with a 5.56 and those tires are about 83-4 in roll i'm gussing you'll turn about 5000 on a 1/4 we run more gear then that with the same size tires on a 1/2 mile your gonna want something to put you in the 6.50 range also before you get tofar into this deal check to see if you can run that bell housing alot of places require a blowproof scattershield now a days


ssaamm
Member
posted October 04, 2003 11:25 PM
ok, my 3-speed has 7 bolts in the side cover, and I don't notice it "neck down" and my 350 turbo yoke slipped right in the tail shaft, but I forgot to look for lines on the input shaft.
does this help me decide to use or lose or is there anything else I should look for?


BK19
Member
posted October 05, 2003 01:27 PM
i you run the right gears in the rearend you will run the trans in 3rd gear so it will not matter what the trans has for gears IE: lines on the input shaft, you only need to know that if you would be running like 3.73 gears and useing 2nd in the trans


ssaamm
Member
posted October 05, 2003 04:47 PM
ok, thanks, I'll keep going with the insatll


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