CH465 4 speed trans stuck in nuetral

[akram]

The truck is a 77 K10, I had the truck towed home after an ignition problem on a roll off and now the trans is stuck in neutral. I tried to take the top cover off thinking I could move the gears manually but the cover won't come off without driving out the pins that hold the shift forks. It acts like the trans is bound up similar to what happens when you have it in 4 wheel drive and you drive on dry ground and the trans get bound up and it's hard to get out of gear. I don't know what could have happened in such a short distance, any ideas?

[mrolds88]

First thing I would do is to take off the shifter and check the tops of the shifter forks. then if that looks good, I would slide the reverse fork then pull the cover to see whats going on inside.

[INSIDIOUS '86]

Sm465? Beat the **** out of the shifter and rock the truck back and forth.

[akram]

I can take off the shifter by driving out the roll pin but I don't think that will help me get the top cover off. The cover will raise up about an inch but it seems like the forks won't let go of the gears. The manual says that you have to drive out the rods that the shifter forks slide on to get the top cover off.

[akram]

Originally Posted by INSIDIOUS '86

Sm465? Beat the **** out of the shifter and rock the truck back and forth.

I might get out my hammer before I go to my last resort and pull the tranny. I did jack it up and spin the tires but that didn't do anything.

[83GMCK2500]

Make sure the transfer case isn't stuck between a gear/position as well. I have never had my SM-465 not go into a gear and it has 500,000 miles on it.

[tucsonjwt]

Just a thought, check to see if the bolt on the clutch adjustment has not worked out too far and the clutch is not really working when you depress the pedal.

[Keith Seymore]

Originally Posted by akram

I can take off the shifter by driving out the roll pin but I don't think that will help me get the top cover off. The cover will raise up about an inch but it seems like the forks won't let go of the gears. The manual says that you have to drive out the rods that the shifter forks slide on to get the top cover off.

That doesn't sound right to me.

You should be able to remove the shift lever by giving the steel retaining cup a quarter turn with a pair of channel locks. No driving out of pins is required.

Unless you really meant shift forks. That I am not familiar with.

K

[akram]

Originally Posted by 83GMCK2500

Make sure the transfer case isn't stuck between a gear/position as well. I have never had my SM-465 not go into a gear and it has 500,000 miles on it.

I checked that, the transfer case shifts smoothly and the truck rolls freely. I've owned the truck since new and the trans has always been a little difficult to get into gear at times and lately it seems to have been getting worse. Why a simple trip on the back of a tow truck would send it over the edge doesn't make sense. My mileage is 135K.

[INSIDIOUS '86]

Well the pull it and get a new one for $75 haha. These are the cheapest and prob most bullet proof trans made

[mrolds88]

Those roll pins only stick in the shifter tower about 1/8" or so. There are actually 2 of them. Another way to turn the cap is to tap it with a hammer and screwdriver. It will rotate and pop up. I think you will find your issue when the shifter comes off. My guess would be that the tow driver may have inadvertently moved the shifter wrong and it jumped the gates in the shifter forks. Also when you get the shifter out and want to pull the cover, make sure the shifter forks are in neutral, then slide the reverse (should be the one on the drivers side) about 1/2 way into gear. The top of the trans will then pull off.

[akram]

Originally Posted by mrolds88

Those roll pins only stick in the shifter tower about 1/8" or so. There are actually 2 of them. Another way to turn the cap is to tap it with a hammer and screwdriver. It will rotate and pop up. I think you will find your issue when the shifter comes off. My guess would be that the tow driver may have inadvertently moved the shifter wrong and it jumped the gates in the shifter forks. Also when you get the shifter out and want to pull the cover, make sure the shifter forks are in neutral, then slide the reverse (should be the one on the drivers side) about 1/2 way into gear. The top of the trans will then pull off.

Here's some pictures just to make sure we are talking about the same transmission. I'm not seeing the "cap" you're talking about other than the whole top of the trans.

[akram]

Originally Posted by INSIDIOUS '86

Well the pull it and get a new one for $75 haha. These are the cheapest and prob most bullet proof trans made

I've got a guy that has three of them, he says that they all work fine but have a whine in 2nd and 3rd, I'm not so sure about those even though they aren't the quietest trans out there, I don't recall mine having a noticeable whine.

[akram]

Originally Posted by tucsonjwt

Just a thought, check to see if the bolt on the clutch adjustment has not worked out too far and the clutch is not really working when you depress the pedal.

The clutch looks like it's engaging and making a good throw.

[akram]

Originally Posted by akram

I might get out my hammer before I go to my last resort and pull the tranny. I did jack it up and spin the tires but that didn't do anything.

Update: I did get out the hammer and put some pressure on the shifter then tap it with the hammer but no luck.

[akram]

Here's the exploded view of the trans and the top cover.

[mrolds88]

OK. I marked the piece we are talking about in red. If you put the screwdriver on the flat part of the hole and tap it medium it should turn and pop loose. let me know how it goes

[86c20]

where the roll pin is if you go up on the tower you have the base of the shifter you see the tin collar that is whatyou want to push down and turn and it comes right out. when i did my clutch this same thing happend i took the shifter back out and used a screewdriver and got one of the rods back in place

[83GMCK2500]

Grab shifter at bend for support, hold it centered, push down on that 2" dome, give it an 1/8th of a turn or so CCW and it should pop up. It takes a decent push, but I've done it on these and early NV4500s by hand. With the tunnel off you can even get both hands down there and use your thumbs. If I were you I'd also drive those rollpins back in to almost flush or fully flush.

[83GMCK2500]

This is what you're trying to push down and turn:


Here one is partially removed:

[akram]

Got the cap off just like you guys said, thanks a bunch, now I'm going in the top with a screw driver to see if I can move any of the forks. BTW it wasn't stuck in neutral, it's stuck in 2nd.

[83GMCK2500]

I thought you said it rolled back and forth... O.O

Now you should be able to see the detents that the end of the shifter ride in, get them lined up in the center and it should be Neutral.

[akram]

SUCCESS! I got the detents to move and lined them up, put the shifter back on and it works! I wasn't able to take the cover off though when I had it in neutral. Perhaps there's another position? Thanks to everyone for helping me through this, you guys are the best!

[mrolds88]

Ak, since you have everything back in order, if you want to take the top off. shift it about half way into reverse, then lift.

[83GMCK2500]

I have a theory...during the move on the rollback one of the shift forks slid from it's neutral position and locked your shifter into 2nd. I guess anything is possible.