5spd stuck in gear (4th?) but not realy??

[ohmrchristopher]

I can select 5th and reverse, but releasing the clutch cause the truck to bog and stall. 

Releasing the clutch in "neutral" causes the truck to move forward. (of course I parked facing the fence, so I'm pinned)

 

1973 620 truck

1975 L20B new rebuild w/ 3000km

1985  FS5W71B 5spd 

 

Everything I'm reading says its all internal and I best be looking for a new transmission....

[Draker]

I have a feeling one of the detents failed and you are stuck in gear. When you select reverse or 5th (both on the same fork?) you are then in two gears at the same time.. and it bogs down because two gears are selected.

 

Honestly, could be an easy fix if you know what you are looking for. But it requires to you remove the tranny and open it up either way.

[ohmrchristopher]

Update:

 

I am stuck in 1st gear

 

We pushed the truck on the street and I was able to drive and turn it around but I am definitely in first gear. Still, can only select 5th and REV and "neutral" is still the gear engaged. I know nothing can be done from the outside, sigh.

 

Can someone please give me a hand with what vehicles this transmission was in? Mike said it's a FS5W71B but when I check http://www.midwesttrans.com/what_fs5w71.html there is no "B" model.

[datzenmike]

This was the 5 speed you got and an L case swap onto it? Oh man. The ends of the three shift rods are in the picture below and should be even across when in neutral. If stuck in first the very top one will be about 1/2" back in the case.

 

In this picture the transmission appears to be in second and the 1st/2nd shift rod is sticking out to the front slightly. If yours was in 2nd it would be easy to just push it back into neutral. Pulling it forward? I don't think so.

 

 

Well probably easier to remove and work on. Rather than remove the front cover again let's try something that is easy and should work in theory..

 

Remove the two bolts on the reverse check sleeve and remove the unit. All '80 and up 71Bs have them. Driver's side of the tail....

 

 

 

It prevents down shifting from 5th into reverse and when removed will give you access to the finger on the striking rod that selects the shift rods.

 

The hole for the reverse check is the bright opening on left side. The bolt holds the 'finger' that selects the shift rods down on the lower left in the picture below

 

 

With shifter in neutral and held over between 5th and reverse... With a flashlight and a strong screwdriver you should see the 1st/2nd shift rod at the top of the stack, with luck, pry it forward into the neutral position.

 

Top one is the 1st/2nd shift rod. This is in the neutral position. If yours is in first it will be back about 1/2" inch. Pry forward.

 

 

If really really lucky you could do this with the transmission in the truck....but doubtfull

 

 

 

How did this happen? Probably the 1st/2nd shift rod was pushed back when the L front case was pushed on. Easy to miss. It happens. To the best of my knowledge this transmission was given to me in good running condition so it's should work fine when 'fixed'. Have faith.

.

[ohmrchristopher]

i had that transmission in since march, been daily driving 40km every day all kinds of diving in between. Just did a drive to Vernon loaded with dirt bikes and gear, 100km round trip. Other than a little more noise and some vibration we cruised at 100-110km/h fine. After the trip I noticed it was hard to get into 4th, had to really ram it backwards. Fast Forward to Thursday night, drove to the country bar fine, drove home fine around 1 am, parked no problem, went to go to work next day at 8am and this is what happened. 

 

No noise, no grinding, pops, hums, whirrs or the like.

 

Too long to recall what those rods were doing when I put the front case on, but like I said been driving fine this whole time. I'll check it out tomorrow and see if I can pop something back into shape?

[datzenmike]

Oh. I figured you just got it in. Well if it was running and then suddenly stuck in first, well that's not so good.

 

Can you get the shift lever into first?

[ohmrchristopher]

no, I cannot get it over to 1st or 2nd, it sits in the middle. I have neutral 5th and reverse, like a sideways letter T

[datzenmike]

 

 

Hmm this is because the 1/2 gate (top one) is moved to the rear and the shift 'finger' is blocked and can't get into that slot. It bothers me that it got this way, it's near impossible other than a severe jolt from the rear.

 

Try removing the reverse check sleeve and prying it forward.

[ohmrchristopher]

pending i am able to get it loose, the what? it it a lack of oil? did something bend or break? I understand what is happening now but what is the WHY?

[Stoffregen Motorsports]

Broken roll pin(s) at the ends of the shift rods? That's common. If that's the cause, replace the roll pin with a "double roll pin" where a small pin is stuffed inside the larger one.

[datzenmike]

He says stuck in first but can't get shifter int first, so the rod must have moved back as well.

 

If the roll pin on the shift fork broke then it could be stuck in first but the shift rod would still work back and forth properly.

[Stoffregen Motorsports]

All bets are off when something breaks.

 

If it did break a roll pin, the piece may hav fallen off the rod or gotten jammed.

[datzenmike]

Update?

[ohmrchristopher]

zero time and zero money. been putting everything into my motorcycle so that i have something to get to work with. possibly sourced a local 5spd. probably wont get into it till October :/

[charbly]

hello! i have been having this same problem recently with my 5 speed in my 1975 620.  i did a 4 to 5 speed swap and since then have worked on the tranny a dealing with this problem as well as having fixed a sheared roll pin.  in the case of the sheared roll pin, it broke on a selector and this results in the feeling of a free swimming shifter where you cant find any of your gears, its as if they have all disappeared. i only bring this point up because a broken pin is a totally different feeling than this problem ohmrchristopher is dealing with.  recently my 5 speed got stuck in first as i had the same symptoms of being able to shift to 5 and R and swing straight thru neutral until i hit 1/2 in which the gate finger was blocking me from selecting 1 or 2.  i had hoped it was a sheared roll pin again that had somehow lodged the selector in 1st gear and was stuck, but upon cracking the transmission open (removing tailhousing) i was easily able to move the 1/2 gate back to neutral, and no sheared roll pins!  it seemed to check out on visual inspection and the fact i was able to shift thru the gears using my hands to select gears with the gates gave me reason to believe it was a simple fluke problem.   this instilled in me  the idea that there were no broken roll pins or mechanical issues to address anymore.  i reinstalled the transmission and the gears shifted flawlessly for a few days driving 25-40 miles a day.  left for the weekend and this morning went to go to reverse out of the driveway and low and behold my tricky little tranny had crept back into first while i wasnt looking! same symptoms, cant get it into the 1/2 gate, stuck in 1st when the clutch is let out.  this all being said i am left to guess that this could be a check ball problem? which i doubt because the check balls are operating correctly by the fact i cannot shift into 3/4 right now because 1/2 is engaged.  so maybe it is a selector rod problem then? the selector has crept out of its original position and when operating correctly is floating closely between 1/2 and 3/4 so its able to engage 1/2 and then slip out into the rest of the gates? or a worn selector? which i also doubt because upon visual inspection it seems to be fine.  im sorry i dont have an answer but i figure all the info i have gathered, although not decisive, will benefit this group problem solving going on.  

random notes i have acrewed in my journey

      -this happens to me only after the car has been parked, i drive into my driveway in 1st and engage the clutch and move the shifter into neutral to park the vehicle

      -before this happens (in the days prior to getting stuck) i feel a stiction as i shift from 1st to 2nd, it doesnt stop the shift from happening, but it feels as though there is resistance to the shift 

      

hope any of this helps.

[charbly]

a crackpot theory afterthought.

to fix this could one remove the 3/4 check ball and spring, move the shifter into 3rd, thereby double engaging the gears, and then very slightly move the shifter hopefully right between the 1st and 3rd position and drop both gears down into neutral, thereby removing your problematic 1st gear from its engaged position?! i guess the hard part would be aligning your 3/4 gate when you reinsert the check ball and spring?  is this at all possible? or am i missing a major problem of removing a check ball and spring before dismantling the transmission?

datzenmike? you probably have a good mental inventory of what you can and cannot do with this transmission and the limits of fixing things without removing completely. any thoughts?

 

[datzenmike]

Seems that the shift rod moves to the rear about 1/2" or so, perhaps at night. This is not likely so any chance that you enter the driveway in first gear before parking? This would mean the shift rod may not have moved of itself but that you managed to slip the selector 'finger' out of the gate without the neutral detent catching and holding it there... and the rod just jumped back into first? Next morning it's already and waiting where you left it. 

 

When you had it apart was there a firm engagement, a 'clicking' into 1st gear? This would be the detent ball settling into it's groove. I've noticed that when shifting slowly, as the shifter nears the gear it almost jumps ahead as the ball runs down hill into the groove. When moved forward there should be an equal 'click' into the neutral position of the 1/2 shift rod.

 

On the 1/2 shift rod end is the little gate that the selector rod 'finger' slips into. Any chance this roll pin is sheared but