Saginaw 4 speed..... Final Saga

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Saginaw 4 speed..... Final Saga

Postby cjbiagi » Sun Oct 13, 2013 8:10 pm

Just wondering if anyone has any issue with their Saginaw 4 speed hanging up in 1st and 2nd gear especially when the car is at a standstill? I have had this issue since the car was new and even took it in under warranty but the problem persists even to this day. This happened with the original shifter as well as the Hurst Competition Plus I have on there. I am used to it and have been driving it like this for 39 years but I am just wondering if this is normal or not? The biggest issue is getting it into 1st when you are getting ready to leave somewhere. Sometimes I have to fight it a bit or get the car rolling in another gear and then it will go right into 1st. I do have a NOS 1st/2nd slider assembly and might pick up a new shift fork as well but it's just odd that it has always done this, so I don't think it's a wear issue since it did it even when brand new. It's had several gear oil changes over the years and I am sure the linkage is adjusted, it's just balky in the 1st - 2nd gear. Once the car is moving there is no issue at all and if I downshift into 1st before coming to a complete stop there is no issue, only at a dead stop.
Last edited by cjbiagi on Thu May 21, 2015 9:05 pm, edited 1 time in total.
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Re: Saginaw 4 speed

Postby 72 SS PNL » Mon Oct 14, 2013 3:22 am

the 1 in my vega , and 68 elco shifts almost like butter

what you describe at stand still sounds like the clutch is dragging , or something is still spinning internally

but obviously something is wrong with yours
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Re: Saginaw 4 speed

Postby gerbsinmd » Mon Oct 14, 2013 8:33 am

I had the same experience with my Starfire way back when. I usually put it in low just before it stopped rolling and then didn't have any trouble, and my buddy with a Spyder did the same thing.
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Re: Saginaw 4 speed

Postby cjbiagi » Mon Oct 14, 2013 10:56 am

Yeah, that works fine while driving but it's more of an issue when you first get into the car and have to get it into 1st, then sometimes it can be a struggle. I don't know if I will do it this winter (probably not) but I should have looked into it further when I did the clutch a year ago and had the trans out :( Anyway, at some point I think I will pull the trans and replace the 1st/2nd slider assembly which is the part you are actually moving when you move the shifter. I inspected the shift fork while I had the trans out and it looked fine but I'll probably get one of those too. The 1st/2nd fork is kind off odd looking and I thought maybe the way it is designed caused a problem, that's why I am trying to determine if this is a common problem or something unique with my trans. Anybody else have any input??
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Re: Saginaw 4 speed

Postby cjbiagi » Mon Oct 14, 2013 10:56 am

Yeah, that works fine while driving but it's more of an issue when you first get into the car and have to get it into 1st, then sometimes it can be a struggle. I don't know if I will do it this winter (probably not) but I should have looked into it further when I did the clutch a year ago and had the trans out :( Anyway, at some point I think I will pull the trans and replace the 1st/2nd slider assembly which is the part you are actually moving when you move the shifter. I inspected the shift fork while I had the trans out and it looked fine but I'll probably get one of those too. The 1st/2nd fork is kind off odd looking and I thought maybe the way it is designed caused a problem, that's why I am trying to determine if this is a common problem or something unique with my trans. Anybody else have any input??
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Re: Saginaw 4 speed

Postby RamIt » Mon Oct 14, 2013 11:20 am

Really sounds like a clutch issue to me especially if it shifts fine while the rear tires are moving.
Is it better if you go to second gear first from neutral then put it into first gear?
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Re: Saginaw 4 speed

Postby cjbiagi » Mon Oct 14, 2013 1:41 pm

It's not a clutch issue, I have had several clutches on this car over the years and they never made any difference with this problem. This even occurs with the engine off, if you just try to run through 1st and 2nd it's a lot balkier than 3rd and 4th which work like butter.
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Re: Saginaw 4 speed

Postby dadhad1 » Wed Oct 16, 2013 11:49 pm

Hi Clyde,

I think what the guys are trying to say (and I agree), is it's potentially a fork/throwout bearing stroke issue.
Sounds like it's just a bit too limited in stroke.
The clutch could be brand new, but if your pivot ball/cable isn't adjusted right, you'll have the exact sympton you're describing.
Have you tried screwing IN the pivot ball a little and tighten up the slack on the cable to the fork?

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Re: Saginaw 4 speed

Postby cjbiagi » Thu Oct 17, 2013 6:34 am

The cable and fork are adjusted correctly, I just replaced everything including a NOS fork, ball stud, cable, clutch assembly throwout bearing etc. There is no grinding or anything, it's definitely a trans issue and as I have mentioned this was like this from the day the car was brand new. I had GM look at it at the time and replaced the shifter, made no difference. It's been like this through several clutch changes and when I had the trans out on the bench I could feel the difficulty shifting it through 1st and 2nd. I had the cover off and inspected the forks and they looked fine. I think the issue is in the slider assembly which is what you are actually moving when you shift. I just wanted to know if this is a inherent thing with these or not?
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Re: Saginaw 4 speed

Postby cjbiagi » Tue Apr 14, 2015 12:53 pm

Just wanted to bring this topic back up because I have had a couple people ask me about any progress I may have made with my trans issue. I am actually getting very close to starting the project to rebuild the trans and hope to begin within the next week or two. I need to get going to get the car ready for show season but I have had a lot of stuff going on this winter that has prevented me from starting. Anyway, I plan to pull the trans and inspect it closely now that I have really studied the operation of the trans and the rebuild process. I feel pretty confident about it so I am hopeful I will find the issue and resolve it. I have a complete rebuild kit with the good forged syncro rings, heavy duty bearings, new countershaft and bearings, tailshaft bushing, seals etc. I also have a NOS 1/2 slider assembly and a NOS 1/2 shift fork. So, when the work begins I will post updates and I hope to become quite knowledgeable with the inner workings when I am done.
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Re: Saginaw 4 speed

Postby Smiley » Tue Apr 14, 2015 6:17 pm

If the syncro keys are too long they preload both syncros for that slider at the same time hindering the one you want from diong its job.
Same thing with the brass rings if they hang over the cone they preload the syncro.
Are you using a roller pilot bearing ?
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Re: Saginaw 4 speed

Postby cjbiagi » Tue Apr 14, 2015 7:23 pm

Yes, I am using a roller pilot bearing and all the parts inside the trans are as GM made it. I do believe there is either something defective, missing, or installed improperly because as I have mentioned, this problem existed from day one when the car was new. I do of course also have new keys and springs in the rebuild kit so I hope I can get this figured out. Why would the syncro keys be too long? Keep in mind this problem occurs even with the engine off (or on) and is only a issue if the car is not moving. If I get it rolling just a little bit then I can get it into 1st and be on my way.
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Re: Saginaw 4 speed

Postby Smiley » Tue Apr 14, 2015 8:29 pm

http://youtu.be/MXsRfbOiBhE
here is a good video on syncros by GearBoxVideo, he has alot of other good trans videos.
not Sag specific but Muncies and T10s use the older brass rings as well.
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Re: Saginaw 4 speed

Postby cjbiagi » Tue Apr 14, 2015 9:15 pm

Yes, I have actually already watched that video before, it is very good. I have been studying as much as I could over the winter so I have an idea of what's going on. I believe (hope) that the problem does lie in the syncro/hub assembly.
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Re: Saginaw 4 speed

Postby Smiley » Tue Apr 14, 2015 10:13 pm

here is the one about the long keys and rocking sliders
https://m.youtube.com/watch?list=PLZOUt ... OmybVKq5-w
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