Bumping out of 2nd

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71DodgeDemon340

71DodgeDemon340

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Hey guys its not an all the time problem and not a big deal at that,
My 833 shifts fine and all seems good but everyonce in a while when im going up a hill and then go back down and let off and let the engine slow the car sometimes the tranny will jump out of 2nd. Push clutch in and shift to second no problem, usually its not a problem cause one hand is always on the shifter. Anyone have this minor issue? Just curious
 
Doesnt do it everytime every blue moon usually when the engine is braking the car around 2k 2500 rpm tranny has been rebuilt shifts fine in every gear no grinding
 
Sorry to go against the folks here, but a bad syncro will NOT cause a trans to pop out of gear. It can't. Once the trans is in gear (2nd in your case), there is no load on the brass ring. It's just sitting there floating around. The main causes for a trans to pop out of gear is bad gear (taper on syncro teeth), bad slider (taper on syncro teeth), or bad fork (worn thin, not pushing the slider all the way to engage the gear). It can be any, or all, or a combination of all three. A bad (worn) rear bearing retainer (usually found on Toyota, Nissan, etc,) will also cause it, but the 833 doesn't use one. A severely bad output bearing will cause it to pop out also, usually only 1st and 3rd.

Let it begin.

Russ.
 
Double M said:
Sorry to go against the folks here, but a bad syncro will NOT cause a trans to pop out of gear. It can't. Once the trans is in gear (2nd in your case), there is no load on the brass ring. It's just sitting there floating around. The main causes for a trans to pop out of gear is bad gear (taper on syncro teeth), bad slider (taper on syncro teeth), or bad fork (worn thin, not pushing the slider all the way to engage the gear). It can be any, or all, or a combination of all three. A bad (worn) rear bearing retainer (usually found on Toyota, Nissan, etc,) will also cause it, but the 833 doesn't use one. A severely bad output bearing will cause it to pop out also, usually only 1st and 3rd.

Let it begin.

Russ.
Click to expand...

Or worn shaft/gear surfaces letting the gear move around once interlocked with the slider.:D
 
I would suspect the keys (or struts) that are worn; they and their associated springs have the job of preventing this. They set in the slider and are part of the 1-2 synchro assembly.

Looks at the parts numbered 13 in this diagram (they keys), and the PN 11 and 14 springs.

http://www.tbtrans.com/a833_4_speed_transmission_pa.htm

I have replaced these in Opel and Muncie 4 speed trannies to fix this exact problem. And yes, the synchro ring itself is not this issue's cause, though I suppose one could say it's the 'synchro assembly'....; I can't say yes or not on the worn parts mentioned.
 
But it doesnt jump outta gear when im driving, only seems like when its going down a hill and i let off and let the engine slow the car down, even then it doesnt do it all the time, never had any issues going forward under power
 
I think this is sliders and gears or combo of both. Both my 69 and my 70 did this. The 70, when I finally sold it, had 150K on the clock. It had had "several engines" in there LOL. Only thing I ever did to the (hemi A833, it was a 6-BBL car) was replace the two big ball bearings and between the original owner and myself, we had each broken one shift fork. I broke the 3-4 fork on a Friday of a long weekend, and got to drive around San Diego for 3 damn days in 1st and 2nd gear.

The 69 had had a much more sordid history. It had worn the main ball bearing, but was making very little noise. The bearing broke, allowing the mainshaft to move fore/ aft in the gearbox, damaging the front of the mainshaft and the interior of the input shaft. I was either stupid, inexperienced, or both, and a machine shop talked me into "pressing a hard ring" over the end of the shaft instead of replacing it. That eventually failed, injected a chip into the cluster / input gear, and pretty much trashed it AGAIN.
 
71
The guys are pretty much on the money.
I used to repair those parts for a living. But sadly my eyesight wont let me repair the sliders anymore. The clutch teeth on the gears though are still no problem.
Yes, it may be a linkage thing, but only if the external levers on the cover are moving around on their studs, preventing your shift from fully engaging the mesh between the clutch teeth and the sliders. Tight nuts is not the answer here. The levers have to physically fit tightly on the studs.If they move around, they make trouble.I red loc-tite them/problem solved.
Yes it could be a back bearing, but you said recent rebuild.
Yes the struts are supposed to keep the slider engaged.EDIT; This is not true at all. I dont know whaat I was thinking. The struts just transfer the slider motion into the brass rings, which lock on to the cones, and synchronize the speed between the two, so that the continuing slider notion can engage the clutch teeth to complete the shift.This happens or is supposed to happen really fast. But when the brass loses its ability to slow the gear down, then you get grinding; which is the slider teeth banging on the clutch teeth. There are several reasons why this can occur.
Theres only one thing that keeps the gears engaged, and that is the detent spring in the cover(old style) or the spring on the roostercomb(new style).And the fork to slider interface has to be in good shape to ensure a deep tooth contact.If either or both of these areas are worn, coupled with worn clutch teeth, then as soon as the coast side of the clutch teeth is asked to work, it just easily kicks the slider back, sending the linkage into neutral.If your hand/arm happens to be hanging off the stick just right, it makes this all the easier.
But once the clutch teeth start kicking the slider back,this problem will only get worse.You might as well drop that baby and get those 6 problematic coast-side,clutch teeth ,back-cut now,(theres always 6,Never seen less, never seen more), while the damage is minimal. Do not let your "rebuilder" talk you into new gears. This is a 5 minute fix, with the gear on the table. Have the other gears checked too.Your "rebuilder" should warranty this on account of he missed it. If he doesnt, I'd find a different guy. If you lived closer I'd offer to fix it for nothing.
You gotta fix this ASAP. Theres not that many guys around any more who can fix the sliders. We're all getting older, and either short sighted, half blind or just plain cant see!If you wait too long, you will be buying parts.
So get it over with.Nobody's lying to you here.
 
AJ/FormS said:
71
The guys are pretty much on the money.
I used to repair those parts for a living. But sadly my eyesight wont let me repair the sliders anymore. The clutch teeth on the gears though are still no problem.
Yes, it may be a linkage thing, but only if the external levers on the cover are moving around on their studs, preventing your shift from fully engaging the mesh between the clutch teeth and the sliders. Tight nuts is not the answer here. The levers have to physically fit tightly on the studs.If they move around, they make trouble.I red loc-tite them/problem solved.
Yes it could be a back bearing, but you said recent rebuild.
Yes the struts are supposed to keep the slider engaged.
But once the clutch teeth start kicking the slider back, those struts give up in a big hurry.This problem will only get worse.You might as well drop that baby and get those 6 problematic clutch teeth back-cut now, while the damage is minimal. Do not let your "rebuilder" talk you into new gears. This is a 5 minute fix, with the gear on the table. Have the other gears checked too.Your "rebuilder" should warranty this on account of he missed it. If he doesnt, I'd find a different guy. If you lived closer I'd offer to fix it for nothing.
You gotta fix this ASAP. Theres not that many guys around any more who can fix the sliders. We're all getting older, and either short sighted, half blind or just plain cant see!If you wait too long, you will be buying parts.
So get it over with.Nobody's lying to you here.
Click to expand...

That was my point (something has been happening to eventually cause the kicking out).
It could even be as simple as a habit of taking it out of second before the clutch is all the way disengaged, and after time it wears the interlock angles, Oops I meant "synchronizer" angles :D
 
71DodgeDemon340 said:
But it doesnt jump outta gear when im driving, only seems like when its going down a hill and i let off and let the engine slow the car down, even then it doesnt do it all the time, never had any issues going forward under power
Click to expand...
That is the normal symptom when this area of the synchro assembly wears or does not engage right: stays in gear under power, pops out when coasting. Why it does not pop out under power, I can't explain, but it does indeed have the exact symptoms you describe. BTW, the 2 cases I have had like this were in 2nd gear one one trannie and 4th gear on another.

Like AJ sez: It won't fix itself. These trannies are not that hard to work on; it is just there are a few tricks to know, and it sounds like this area was missed. The standard rebuild kit these days won't have these springs and keys/struts, so I suspect most people don't know how they work or even what they do!

AJ, I never knew about wear on the clutch teeth so thanks for that.

(BTW, I'll fix it in trade for a 340 block LOL)
 
67Dart273 said:
a machine shop talked me into "pressing a hard ring" over the end of the shaft instead of replacing it. That eventually failed, injected a chip into the cluster / input gear, and pretty much trashed it AGAIN.
Click to expand...
FYI, I had the hardened ring fix done on a '71 Saab trannie (which all failed due to too small a needle bearing design on the mainshaft's nose) and it held up fine; the guy made it a bit longer than the original and used better needles, to correct a faulty factory design.
 
nm9stheham said:
That is the normal symptom when this area of the synchro assembly wears or does not engage right: stays in gear under power, pops out when coasting. Why it does not pop out under power, I can't explain, but it does indeed have the exact symptoms you describe. BTW, the 2 cases I have had like this were in 2nd gear one one trannie and 4th gear on another.

Like AJ sez: It won't fix itself. These trannies are not that hard to work on; it is just there are a few tricks to know, and it sounds like this area was missed. The standard rebuild kit these days won't have these springs and keys/struts, so I suspect most people don't know how they work or even what they do!

AJ, I never knew about wear on the clutch teeth so thanks for that.

(BTW, I'll fix it in trade for a 340 block LOL)
Click to expand...


Thanks huys im kinda bumed now, i was hoping it was a common characteristic of the 833 as is the 4 speed whine. I really hope the guy who rebuilt the trans actually did what he said he was gonna do and didnt half a55 it, he said he only replaced anything that needed replaced and everything else looked good, like i said its not to a point where it does it everytime, may do it once every 10 or 15 times i drive it, usually i try not to let the engine brake the car and let them SSBC big bite rotors up front do the stopping, i think eventually down the road i may have it gone through again. But honestly i keep my hand on the shifter at all times, just a habit lol.
Its a original hurst shifter (not to the car) and it shifts like butter. Wonder if the vibration could cause it to release 2nd gear, when and rarely when it does it i dont hear any noise its almost like you just pulled the shifter to neutral, no violent action
 
What vibration? You didnt mention any vibration before now. I checked.
Ooooh booy. Why did you withhold this information? If you were here I'd punch you in the arm.Hard! lol.
And nooow you mention a whine. After I spilled all my secrets.
I have got to start asking more questions.


So; these are not normal. If the tranny is whining, its like a cat when you're standing on its tail. He's telling you something is wrong.
Jumping out is one thing.We already talked about that.
Whining is another
And vibration is a third.
Each of these by itself can have their own solutions. When all three are in concert, it could spell a fourth solution.
-Lets talk about the whining.There are several possible sources of that in the tranny. The first one is bearings. The second is tooth contact. The third is misalignment.
-Lets talk about vibration.There are no obvious sources of vibration inside the tranny.Other sources are the clutch assembly, the driveshaft assembly, and other.Heres the thing; vibration can be a major enabler of jumping out of gear during coasting or deceleration.You need to fix this first. I'm not saying your tranny is ok,cause its not. I'm saying the vibration could be driving the condition.
-Now lets talk about whining again. Lets say your pilot bushing fell out. (Dont laugh,it happens). This would immediately produce a vibration as the disc drops off center. It would also drag the input shaft off center. This would tip the inner race of the front bearing, driving the balls into the outer races, and probably squeezing the oil film down to nearly nothing.And you can imagine the rest.Thers something else that would happen. The off-center running input, would apply pressure to the needle bearings at the front of the output shaft,eventually causing the nose to fail. And a third thing that would happen is, finally, the whining; as the edges of the drive teeth on the off-center running input gear, dig into the teeth of the cluster drive-gear.
So you can see that just that little $3(1999pricing)part COULD cause all three symptoms.Again, Im not saying you need a new bushing. I'm just presenting you with a possible solution.
So, bottom line is this; find and fix the vibration. This may forstall the tranny rebuild.At least for a while.
 
AJ/FormS said:
Doublem
Rob said "synchronizers". He did not say brass rings or synchronizer rings.
And he is right.
Its a system. You're playing symantics, and not helping the OP one bit.
Click to expand...

Judging by the response to what I wrote, I'd say everybody knew exactly what I was talking about. I don't see where Rob said I was mistaken. After 50 years of building standards and listening to customers, I figure Rob meant the syncros. If he didn't, then I apologize.

Or do I apologize to Rob through you?

Russ.
 
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