Question for transmission guys

I have a Borg Warner ST-10 that wont stay in gear. In all the forward gears I need to keep pressure on the shifter, otherwise it will pop out of gear.

Wondering if this would be a trans problem, or a shifter problem.

Thanks

 

Could be worn gears, worn main shaft bearings, worn shifter bushings/linkage, or mal-adjusted shifter. Take your pick.

 

all gears, or just one or two?

 

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all gears, or just one or two?

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1st, 2nd, 3rd, 4th. It almost acts like the shifter doesnt have enough throw to go into gear.

Is a brand new Hurst Super Shifter. I am going to look at it this weekend to make sure I used the correct rods and arms that came with the kit. I will check the stops again too.

Other than that, Im not sure.

 

sounds like you answered your own question.
It might be worth disconnecting each shift link rod and engaging each gear at the gearbox, then at the shifter, then seeing if the link will drop back in place. This will tell you if it is a shifter /transmission lever travel mismatch.
Mart.

 

Its possible if the transmission has a lot of miles (most t-10's are on at least their3rd or 4th life) that the syncronizers ( br*** blocker rings) are worn along with the corresponsing syncro teeth on the speed gears. If this wear is significant it can allow the transmission to slip into neutral at the slightest change in acceleration or speed.

Frank

 

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Its possible if the transmission has a lot of miles (most t-10's are on at least their3rd or 4th life) that the syncronizers ( br*** blocker rings) are worn along with the corresponsing syncro teeth on the speed gears. If this wear is significant it can allow the transmission to slip into neutral at the slightest change in acceleration or speed.Frank

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I am afraid that may be the case, the date code on the case is 8/74.

I am going to double check my shifter installation this weekend, but if it looks good, I may end up pulling the trans and seeing if I can work something out with the place I got it. It was supposed a good used trans, not a builder.

 

Was it OK before the shifter installation? Or had you never run it before?

Sounds like a shifter issue - either incorrectly adjusted or wrong arms on shift levers (too long - unlikely).

Most Hurst shifters have stops on the top of the shifter gate that you adjust to keep from "over shifting" and bending shift forks - the one on the front does 1st/3rd, the one of the back, 2nd/4th. If they're adjusted in too tight, it could be enough to engage, but pop out unless held just like you describe.

Good luck!

 

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Was it OK before the shifter installation? Or had you never run it before?

Sounds like a shifter issue - either incorrectly adjusted or wrong arms on shift levers (too long - unlikely).

Most Hurst shifters have stops on the top of the shifter gate that you adjust to keep from "over shifting" and bending shift forks - the one on the front does 1st/3rd, the one of the back, 2nd/4th. If they're adjusted in too tight, it could be enough to engage, but pop out unless held just like you describe.Good luck!


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This is the first time I ran it. Ill go through the shifter and see if I screwed something up with that.

 

Flat ernie, I don't mean to be disagreeable but you've got the gear sequence wrong. The rear shift stud on the side cover controls 1st and 2nd gear. the front shift stud controls 3rd and 4th gear. With the shift arms facing upward the second arm is shifted rearward for 1st gear, then shifted forward (through neutral) for 2nd geark. Then the forward arm is shifted rearward for 3rd gear and last the front arm is shifted forward through neutral to engage 4th gear. The shift stud on the rear housing is for reverse.


Frank

 

Frank,

You're absolutely correct - however, I was talking about the shifter ***embly itself and not the transmission. There are adjustable stops so you can only throw the handle so far - these are on the body of the shifter.
However, having found a picture, I can see I was wrong anyway - the stops are below the pivot which makes them backwards from what I said. I must have been thinking along the lines of a T5 shifter...
Hopefully, this pic will explain it:


In this pic - "B" is the stop for 2nd/4th & "A" is the stop for 1st/3rd - make sense?

 

FlatErnie, Thanks for clarifying. Now I think we are both on the same page.

Frank

 

Can someone please explain to me how bad synchros (which help gears engage) can allow gears to pop out of mesh once they are enmeshed?

 

BlownOlds, it is actually very true about the synchro's being worn causes the trans to pop out of gear. It has to do with the design of the trans. The gears themselves are not really moved when shifting, it is the synchro's that move to engage or disengage the appropriate gears. In other words, the gears stay meshed together, and the synchro's actually slide into the gears or not and this causes the gears to transmit the power or not. Clear as mud?

Couple notes for clarification: this above explanation ***umes the trans is a synchromesh in all gears. Some older style trans are not synchro in first gear.

Reverse gear is not synchronized, that is why it crunches, it actually slides the gear into position in most transmissions, even if all forward gears are synchronized.

If you can see a trans with the cover off, this will be all much easier to understand.

 

Aha. I think mebbe I'll stick with hydro's, LOL