Sounds like a plan. Should the 2 main shafts be replaced? Also is there some kind of identification chart for super t10’s or are they all fairly similar throughout the years of use? I’m assuming my came in a GM originally but not 100% sure
New guy 79 factory 4 speed wagon.
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1st gear and 4th gear appear to have nice sharp clutch teeth. 2nd and 3rd are a bit rounded and should be replaced to have the most reliable unit.
You are missing an idler shaft at the top left of the picture.
There are many online calculators to figure out what drive and driven gears you need in the transmission, based on the tire size you are using.
With a 3.89 rear and a 26-inch tall tire, using my own designed calculator I figure you need a ratio of 3.13:1 between the drive and driven gears...8 drive and 25 driven teeth are very close, if that combination is available for the T10. If not, gear adapters can be had to make up the difference between what the drive/driven gears can do. Such adapters were even used in factory GM applications.
Another option: 8 drive/20 driven with 0.800 adapter
Depending on what gears available, you may have to be creative since 3.89 wasn't a factory gear option.
You are missing an idler shaft at the top left of the picture.
There are many online calculators to figure out what drive and driven gears you need in the transmission, based on the tire size you are using.
With a 3.89 rear and a 26-inch tall tire, using my own designed calculator I figure you need a ratio of 3.13:1 between the drive and driven gears...8 drive and 25 driven teeth are very close, if that combination is available for the T10. If not, gear adapters can be had to make up the difference between what the drive/driven gears can do. Such adapters were even used in factory GM applications.
Another option: 8 drive/20 driven with 0.800 adapter
Depending on what gears available, you may have to be creative since 3.89 wasn't a factory gear option.
If the journals of the mainshaft aren't scored, it can usually be reused.
The shaft in the center of the cluster shaft is typically replaced with a rebuild kit.
Looking at the front of the transmission, you can tell if it is for a GM application based on the transmission-to-bellhousing bolt pattern GM and Ford are different. I think the AMC units use the Ford pattern.
The GM pattern will be the same as your Saginaw.
I was comparing the saginaw and ST10 last night and the shifter location. I can use the factory hurst competition plus shifter on the st10 I believe but would have to modify the mounting bracket that was on the saginaw. Or can I just just buy all the 74-81 F body shift levers f then like you said, look at the 55-57 Chevy shifter that comes up through the floor? I’m a little ways off from worrying about the transmission right this second. I just took the steering column out last night. Just trying to plan ahead
If you can use the Saginaw bracket, you may not have to get a different handle, as the shifter will come up very near the same place as the Saginaw. The midplate in the T10 will push the shifter rearward a bit, but if you are going to modify the bracket, perhaps you can compensate for that difference during your modification.
Does the Saginaw already have a Hurst shifter? or the original ITM shifter? The ITM shifter already has quite a short throw. You should be able to use the ITM shifter on the T10; the bolt pattern is the same. If the T10 already has levers, you only need to make rods. The reverse rod will be the most challenging due to its proximity to the shifter location, but anything is possible.
If the Saginaw levers fit the T10, again, you only need to make rods.
In the mid 1980s, I put a Hurst Competition Plus shifter in my V8 Vega with a Saginaw and the throws were very long compared to the short throws of the stock ITM shifter setup on my Malibu wagon. If the levers are too long, the throws will be long.
Does the Saginaw already have a Hurst shifter? or the original ITM shifter? The ITM shifter already has quite a short throw. You should be able to use the ITM shifter on the T10; the bolt pattern is the same. If the T10 already has levers, you only need to make rods. The reverse rod will be the most challenging due to its proximity to the shifter location, but anything is possible.
If the Saginaw levers fit the T10, again, you only need to make rods.
In the mid 1980s, I put a Hurst Competition Plus shifter in my V8 Vega with a Saginaw and the throws were very long compared to the short throws of the stock ITM shifter setup on my Malibu wagon. If the levers are too long, the throws will be long.
I thought the 4-speed Malibus came with ITM shifters, so it may not be original. The ITM shifters look just like a Hurst shifter, but have ITM instead of Hurst stamped into them. The ITM shifter box has the same mounting holes and thread as the Hurst box, so no mods are necessary to the GM bracket.
In the parts book, there is only 1 listing for a 4-speed shifter (PN 470204). It is an ITM shifter, not a Hurst shifter. Russ at 4speedconversions.com has pictures of a factory ITM 1978-1981 A body shifter.
Fun fact: In the 1980s I had a1969 LeMans with a 350 2 barrel with a factory Muncie 4 speed, and it was a Hurst box (I knew the original owner, who ordered the car). There were some differences from the aftermarket boxes, though. The factory box had rubber grommets in the shifter lever holes while the aftermarket ones do not. The holes in the lever were also slightly smaller than the aftermarket, so the plastic, bronze, or steel bushings could not be used.
In the parts book, there is only 1 listing for a 4-speed shifter (PN 470204). It is an ITM shifter, not a Hurst shifter. Russ at 4speedconversions.com has pictures of a factory ITM 1978-1981 A body shifter.
Fun fact: In the 1980s I had a1969 LeMans with a 350 2 barrel with a factory Muncie 4 speed, and it was a Hurst box (I knew the original owner, who ordered the car). There were some differences from the aftermarket boxes, though. The factory box had rubber grommets in the shifter lever holes while the aftermarket ones do not. The holes in the lever were also slightly smaller than the aftermarket, so the plastic, bronze, or steel bushings could not be used.
This is the shifter that was in mine with the Saginaw. Are these pretty pretty reliable? I don’t know if I should rebuild it or not but nothing with the saginaw ever gave us any trouble. I was just wondering since it’s out of the car. Can you still get parts for them even? The car has right at 130k miles on the odometer. I’m hoping one of these days this week my brother will get some free time so we can start really comparing the two transmissions and shifter bracket side by side on a work bench. He’s far more knowledgeable about this stuff than I am. I took the steering column out of the car and he tore the whole thing apart in about 6 minutes. Someone broke into it back in the late 90’s and we haven’t used a key to start it since then. He said I need to get that fixed so my dad can drive it if he ever wants to.
That shifter is reliable and parts are still available to the best of my knowledge. On Paul Cangiolosi's youtube channel, that I shared earlier, he has rebuilt shifters.
If that is the T10 on the floor, it is a GM version, but is not a Super T10. The Super T10 had a 26-spline input shaft and a TH400-style output shaft. The 10-spline input shafts were used in the earlier T10 and had a TH350-style output shaft. It may have been apart before and different parts put back in it.
The steering column is unique in the manual transmission cars because of the key release lever. The tilt version of that column is especially rare. They can be made from parts from other cars; I have made a few custom tilt key release columns for 1982 and later models, since they weren't made for those years.
If that is the T10 on the floor, it is a GM version, but is not a Super T10. The Super T10 had a 26-spline input shaft and a TH400-style output shaft. The 10-spline input shafts were used in the earlier T10 and had a TH350-style output shaft. It may have been apart before and different parts put back in it.
The steering column is unique in the manual transmission cars because of the key release lever. The tilt version of that column is especially rare. They can be made from parts from other cars; I have made a few custom tilt key release columns for 1982 and later models, since they weren't made for those years.
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