Hi guys, first post here, let me know if i am doing anything wrong.

I have an 86 f150, 4x4 with a 302 and a (I think) NP 435 4 speed transmission. I haven't run it in a couple years, but after having lots of wiring issues, we got it started and drove it around town a bit. It shifted bad, even slowly double clutching it, so I decided to do the clutch. This is my first time doing that, and it was difficult but I got it all done (Haynes manual) and I am trying to get the shift lever back in, and it will not seat properly. I can get it inside, and I pushed the spring cap down and twisted and it stayed, but it won't go into gear. To make sure it wasn't aligned, I started the truck and tried shifting, the lever seemed like it went into second gear but it wouldn't engage and I couldn't get it in any other gears including reverse. I pulled it back out and have tried moving it around and getting it positioned different, and that didn't work. Any ideas? Anyone had this issue?

edit- I should explain better- I am not anything resembling a mechanic. I have done little things on all my cars and trucks, but never a job this big on any vehicle. I am really excited to learn more, but you should all know I am very much a novice. Thanks in advance for the help!

 

https://www.garysgaragemahal.com/clutches-and-linkage.html

https://www.garysgaragemahal.com/manual-transmission-shift-levers.html


I'm not a manual tranny expert but, those links may help. One of the Dave's or Karl will chime in soon.

Here's for the NP435,
https://www.garysgaragemahal.com/np435.html

 

Thanks! those diagrams are helpful.

 

Take the shifter out and make sure both rails are in the neutral position.

 

Can you please post a picture looking straight down where the shift lever fits? You should see 3 rails (rods?) side by side.

 

Does the retainer cap look like this one?:




A picture down inside the tower will still help.

 

okay, thanks all. I have it in my in laws shop, I will go get a pic and post later today, and yes kr98 it is that style. I went and asked a shop today and they said the same of the rails being in neutral, I will take a look and see if i can tell what y'all are sayin.

 

Okay got a handle on the rails now, but they are not moving right. I started with the passenger side one backward and the driver side lined up, but once I forced the passenger forward, the driver side shifted as well, and I cannot move them back? Any Ideas?

this is how we started

and now it is like this

 

Makng some progress.

Normally, when shifted into reverse, do you move the lever to the right against a spring and then aft? If so, it looks like the transmission is in reverse right now.

There are three rails side by side, each with a cast iron “gate” on top. The one on the far left has a spring-loaded plunger sticking out and blocking that gate. Use a big screwdriver or narrow prybar to move that far left gate aft to line up with the other two.

Once all three gates line up, reinstall the lever and you should be good.

 

So, @kr98664 Karl, are you saying to 1) push the detent in (red arrow) and then move the shift fork to the rear (yellow arrow)?

 

You don’t necessarily have to depress the plunger (red arrow). It will help give your screwdriver more to grip with it out of the way. But you could even pry from the outside of the gate casting.

That plunger does not lock out fore/aft movement of the gate/rail. It only provides the spring resistance you have to initially overcome when moving the shift lever sideways for reverse.

 

Forgot to add one important tip:

Take any tension off the transmission to make it easier to slide that shift rail from reverse to neutral.

Chock the front wheels. You could depress the clutch pedal, but that will be awkward to hold while trying to manipulate the shift rail.

If 4WD, set the parking brake and shift the transfer case to neutral.

If 2WD, release the parking brake and jack a rear wheel off the ground. If a limited slip differential, you’ll need both wheels in the air.

 

okay so I have done all of that now, The only thing i have not tried is to depress the plunger and apply rear pressure simultaneously. I did have my transmission shop look today, they had the same experience i did, saying it is locked in reverse and that we need to drop the transmission again so that they can take a look and fix it. so i either have to tow it back to my shop and drop the transmission myself, or pay them 1000 to do that and then go from there on the internals. Has anyone had it get stuck in reverse like this before? I'd love to avoid all that but it looks like I'm going to tow it back to do that all over again.

 

Please see my previous comment in post #11 about that plunger. It does not act as an interlock to keep the rail from moving.

If your transmission shop is stumped, so am I. From all appearances, the rail at the far left got moved out of the correct position. I do not understand how it does not just pop back where it belongs.

One thought is to peel back the carpet or floor mat. Does your truck have a removable sheet metal cover on the transmission hump? If so, remove that and then unbolt the shift tower from the top of the transmission. Then you can test the shift tower from the comfort of your workbench. If something is preventing the shift rail from moving, you can isolate if the tower or transmission is at fault.

If you do have to remove the transmission, make a flat cover to bolt in place of the shift tower. Sheet metal or thin plywood will work. This will give you more room to maneuver the transmission under the truck. Drain the oil, too. You may have to tip it on its side to get it out under the frame rail.

 

Thanks Karl! I'll give it a shot. I don't think there is a removable plate in the truck, i started on dropping it tonight and I will take it all the way down and pull the top off the transmission tomorrow.