Seleting reverse on a 12speed

[mrsmackpaul]

that little doodah thingy is meant to come out with the air line I think you'll find and all the plastic air lines are meant to have one in them to stop them collapsing when you do them up

Just use some long cir clip pliers should have it out in jiffy I think

Paul

[Challenger]

Push the smaller cylinder out of the larger cylinder. That way you can remove the snap ring from the side its closes too. If the snap ring looks fine and just pi$$ing you off, just leave it alone, it will be fine.

When you break it down, the hi/lo cylinder should just be an empty tube with a snapring. The piece making the snapring a pain, is just another cylinder piece that slides out (which has 2 different size orings on it.)

And like mrsmackpaul said, the metal piece in the airline fitting just keeps the line from collapsing. This WILL NOT cause your problem. Maybe if it was missing and the line collapsed, it could cause a problem.

The oring kits comes with extra orings, not sure how many. Every size should be used, some of the sizes just have extras.

Brakeclean is ok, aslong as its not touching any orings you plan on using.

[Full Floater]

Once again you have an encouraging response, many thanks! I will be back working on it again in the a.m. I will try to push the smaller cylinder out, I did try a bit but as it wouldn't budge I left it alone until I found out more. I'll make a proper attempt now.

Ah ok, now that I look at that piece again, it makes sense. Didn't even realize the air line didn't have it inside.... That's nice to not worry about that..

You will hear back from me soon.

[Full Floater]

Ok so I got it all back together, replace every oring and slapped it back on the trans. Hooked up all the air lines correctly, and Im not getting neutral or reverse at all now. Hi and lo work but every selection on the splitter including neutral and reverse is forward. So im going to pull it back off and see what I can find.

[mrsmackpaul]

the little doo hickys that hang off the bottom of the air rams sounds like the reverse one isnt in the selector fork sounds like you need to lift the lid and have another go by memory it hangs on a angle and can be a bugger and involve some new language and can take a few goes or at least it has with me

I only stick one or two bolts in the lid and just blow some air down the air lines to make sure its ok and working before fully assembling again

Paul

[Full Floater]

I was able to peak through as I was lowering the lid to ensure that the doo hickeys were in there slots. I have the cover off again, I cannot move the neutral reverse doo hickey/ram at all. I noticed this a I put it on to but just didn't think much about it. I think it may be an issue with the locking pin?? As I kind fiddled with it to get the rams back in

[Full Floater]

Nevermind, now I can move it, just had to reposition the other one in order to allow the reverse one to move

[Full Floater]

With the Hi Lo selector in the middle (locking pin) position, the reverse ram will move to the reverse position when air is applied to the side port. And back to neutral when air to the rear port. When the reverse ram is in neutral, the Hi Lo will function properly also. Do the selector forks in the trans have to be in a specific position when installing the cover?

[mrsmackpaul]

I dunno but with any box I always make sure they are all in neutral before I drop the lid on and I just a farmer no expert at any of this maybe Challenger might know for sure

I feel if you but it in neutral on both forks and the air rams are in neutral you should be ok

Paul

[Full Floater]

Yeah that's what I would like to try. And to select neutral on the shift forks in the trans, what am I looking for? Do I just want the forks to sit freely? The trans and selector were in neutral when I removed the cover, and im attempting to assemble with the shifter and selector in neutral. So I guess all that im looking for is the forks to be in neutral to now... I think..

[mrsmackpaul]

I got a book years ago have never read it until now I have always found these transmissions pretty simple so I have scanned some pages dunno if it will help or not

now you could read thru all these instructions but what I would do since you have plenty of room is see the little woman go into her hand bag and grab her compact mirror I think thats what they call them the little mirror they use for lipstick and stuff

pull the lid off the top of the transmission and with mirror and a torch have look at the gears them selves and they should look like this

the high low dog should be in the middle as shown and the reverse should be forwards then get the lid doo hickys lined up as shown gently lower on and bobs your uncle but I do know the selector forks have to be in neutral as does the lid as I said before I have developed a whole language trying to do this on the side of a road once when the bolt that holds the selector fork in place on the shaft came out in the high low section but thats a story for another day

the lower picture the transmission is drawn in neutral so if you get it to look like that you should be right

good luck

Paul

[Full Floater]

Wow thanks for taking the time to scan those pages. I didn't know about that adjustment procedure. I'll save that part for later and I'll make sure those forks are in those positions, which I don't think they were; tomorrow morning. Thanks!

And yeah, another day id like to hear that story of the bolt falling off. So id better double check that they are tight!!

[Challenger]

When installing the top cover, the hi/lo sliding clutch shifter (the part in the trans) should be in neutral (inbetween gears). The reverse shifter should be in neutral (toward the front of the trans).

Have the hi/lo shifter in the trans in neutral (inbetween both gears). Put the reverse shifter in neutral (shifter should be moved towards the front of trans).

Like mrsmackpaul said, the top cover reverse/neutral shifter needs to be on an angle to engage the trans shifter.

I lower the top cover on the trans, leave the cover up about an inch, and use a long flat tip screwdriver and move the top cover shifters into place. It can take a few times to get the shifter to engage. Ive never dropped the cover on and was lucky enough to engage both shifters. Ive tried, but it never works out.

You got your top cover together, all you got now is dropping the cover on. This is trail and error period, sounds like you figured that out already.

You probably missed the reverse/neutral shifter the first time you dropped the cover on. That would be why you didnt have reverse but had hi/lo.

When you couldnt get the top cover shifters to move, you probably got the shift rails stuck on the lock pin which is inbetween the rails. Just like you did, you just move them around until they are free. This happens to me too.

Dont worry about the adjustment the instruction book is talking about. Tech manuals make things more difficult then they need to be. If you have your gears, YOU ARE GOOD TO GO.

[Full Floater]

Ok I got it!! I ended up using a screwdriver as you described and the selector is now working as it should, thanks! however; im kinda back to the same problem. When the trans has warmed up, it becomes very stubborn to get reverse again. Today when I test drove it, all was well so I went and did a load, and about 10 miles into the run, no reverse for the life of me. If I had tools with me I would have popped that cover now that im familiar with it but I didn't have any tools really. So I attempted to pour cool water on it for a while to get the temp down (it was just barely warm), that did nothing, I tapped it with a hammer a bunch and that's when I finally got it to engage. Which was good because I was faced into a dead end road. I engaged and disengaged it a number of times to try and free something up , then 5 miles later, same thing, no reverse. But after working the toggle a bunch and rocking the truck back and forth, it engaged. Then on the way home it was ok, not that easy but there was not much fighting to get it to engage. And that's where I left it now that darkness is upon us.

I made sure I was at or over 100lbs of air, the filter is new, there is tons of pressure at the air line when its disconnected and the inlet fitting is free of obstructions. So, im 99.9% sure that it is getting all the air it needs. I lightly coated the rams and all the orings with grease when I installed them to lube everything up nice.

[Challenger]

Next time it doesnt select reverse, put the stick in neutral but leave the selector in reverse. Its important to do this while trans is acting up.

1 Remove the reverse airline, check for air, air should be applied at this time. Reinstall airline

2 Remove the neutral airline, check for air, no air should be applied. Reinstall airline

3 Remove the hi and lo airlines, one at a time. Both should have air, this puts the hi/lo sliding clutch in neutral.

This will eliminate any possible intermittent air supply problems.

[gearhead204]

also check for air in the exhaust line when in reverse, I finally fixed mine, if below 40 degrees I had either no or occasional reverse but mine was bypassing in the shifter handle. I had put 2 rebuild kits in it over the last 4 years but still no cold weather operation. well 385 bucks later it now shifts like a new trans again. when I selected reverse, I would have air escaping thru the exhaust port on the shifter I could some times block the exhaust and make it shift.

[Full Floater]

Good to know, thanks. I'll check that out. I cant hear any air escaping but who knows.

[mrsmackpaul]

got some more stuff scanned the books is very informed compared to me so I dunno LOL

it has a lot of pages that just seem repeated but look the same so I only scanned some

heaps of good advice coming now what ever the problem is its going to be simple like me I feel

I wonder is your inter locking plunger sticking so it cant shift into reverse ???or maybe the air pressure isnt working at the right level or maybe the exhaust is blocked and not letting the air out or the knob on the stick has got a blockage I would be thinking thought the interlocking plunger is sticking every now and then

When you are taking the lid on and off make sure you dont use any silastic type stuff to glue the lid back on as it oozes out and ends all thru the box and will stop the sliding dogs going in and out and thats a big job to fix I know what a mess LOL

when the lid is off do the selector forks slide in and out ok are the poppet balls getting stuck on the rods or in the hole I cant remember if high low and reveres has these or not pretty sure they do maybe someone has somehow got silicone inside one of these and its stopping the ball coming back ??

Paul

[Full Floater]

Im thinking that its either a sticking locking pin or an air blockage/pressure issue. When the cover is off, everything seems to be fine, as long as the high-low is in its neutral position, the reverse ram will work well. This is with air and not touching the ram itself. Yeah maybe there is silicone somewhere. I put a THIN layer on the first time I set the lid on but I let it set up mostly before I set the lid on, then once I realized I was going to be taking that thing on and off a few times, I cleaned off all the silicone with a rag so it wouldn't start making a mess. I was careful not to get any in the gearbox