Hello all, my transmission has been acting weird lately, not sure what the issue could be.

I drive a `93 f150, 4.9L, 4 speed with overdrive, about 91k miles.

Roughly a week ago I was getting back from a 30 min drive and was parking my trailer (back and forth back and forth). While trying to squeeze the trailer into the spot, changing from 1st to Reverse a lot, all of a sudden the truck stopped going into gear, as if there were no gear slots (sorry to butcher the terminology). It was as if there was only the neutral position, no matter how hard I forced the stick, it didn't go into any gears.

I gave it about 10 minutes and came back, then boom, back to normal, shifts fine, no problems at all.

A few days later I changed out my trans fluid and the problem never resurfaced, until today (a week or two after the first problem). Within the first 30 minutes of a 3 hour drive, for about 10 seconds in a traffic jam, the truck wouldn't go into gear again, just stayed in neutral. I pulled over and let the clutch out and pushed it back in, and then it went into gear, didn't have to fight it at all. After that it was fine for the rest of my drive.

Very strange, any ideas would be very helpful. Someone mentioned it could be the slave cylinder is starting to go, what do you guys think? I am a bit clueless.

Thanks in advance

 

Does it physically prevent you from going into gear, or are you saying when the stick is where it should be, it's like it's in neutral?

 

Hey Ian, thanks for the inquiry. Yes it physically preventing me from shifting the stick up or down into the gears. It wont physically move into any gear from the neutral area no matter how much I force it, almost as if no slots exist, just the neutral area.

 

Just my experience but the last time i something like that happened to me the springs in the clutch plate were falling out....have you been getting any clutch chatter?

 

Hey Mike. Can you explain what you mean by clutch chatter? The clutch squeaks or creaks a bit right under the dash when I engage it or let it out, but I don't think that is what you mean. It doesn't feel like a mechanical thing in the transmission, maybe just a lack of WD-40 on the moving clutch pedal parts under the dash.

One thing that comes to mind is when I start the engine, there is a very quick rattling sound coming from the transmission area, directly under the stick. Not sure if this is normal, like just stuff starting up, or if it is a new sound, can't say I noticed it before though.

 

Trying to force it is only going to ruin the shift forks in your transmission ... DON'T TRY FORCING IT!

You clutch is not disengaging and it's likely the master or slave unless your clutch disk is coming apart.

I suspect it's the master, have you checked the fluid level in it?

-Enjoy
fh : )_~

 

Apologies, I definitely am not forcing it. Just once or twice I put pressure towards one of the gears and there was no change at all, so I know that even if I do start forcing it, I don't think anything would happen. I appreciate the heads up though! Fluid level in master seemed alright at a glance a couple days ago, I will do a closer inspection on that in the morning. If fluid is fine, what do you recommend?

 

I believe that truck has an internal slave ... Someone else needs to confirm this for I am not well versed on the F150.

If the slave is bad it will be leaking fluid ... The master reservoir will show that (low or empty).

If you can get it in gear without forcing, keep holding the clutch down and see if it starts to take off like you were letting the clutch out (but don't let the clutch out) ...

What Mike1 was saying about chatter is, the dash will shake as you are letting the clutch out to take off.
This is signs of a bad clutch!

-Enjoy
fh : )_~

 

Clutch chatter is when the clutch disk is starting to get worn or has loose springs and as you described it starts to rattle when you start the truck...sometimes while it's in neutral and sometimes while you have the clutch depressed. With 91k on it, it might just be ready for a whole new setup.

 

Apologies for the delay, haven't been able to respond for a couple days. Drove the truck about 4 hours straight while keeping an eye on the problems everyone has addressed.

As for clutch chatter, doesn't seem to be any. Dash doesn't noticeably shake or rattle. Also, clutch doesn't start to disengage and the truck doesn't start to move when the clutch is engaged.

Master cylinder is full, when I take the cone shaped rubber gasket thing out of the top the fluid is right there and dripping off of the rubber thing, displaying that it is very full. HOWEVER, it could be a couple drops low, but an extremely small amount if any, because there is no fill line it is difficult for me to tell if it leaked a couple drops from when I filled it a year or so ago. But, it seems fine to me.

This whole thing is strange because the problem has happened 2 times total now over the course of 2 weeks. The first time was about 5 minutes of not being able to engage any gear, and the second time was a couple days ago for about 10 seconds, after the 10 seconds (and letting the clutch out and pushing it back in) everything was about normal. The first time it happened I was stopped, trying to put it into reverse and 1st gear. The time it happened a couple days ago I was in 1st or 2nd gear in traffic and only lasted a few seconds. Very strange to me.

Not sure what else to check. Thanks to everyone for the help thus far, I am a little clueless when it comes to in depth things like this, so much appreciated. Any other suggestions or things to check will be very helpful.

 

When it acts up, try turning the engine off and see if it goes into gear. That should help isolate whether or not its a clutch disengagement problem, or an internal shift-fork problem.

 

Great Idea. I will do that. If my memory serves me right, the first time this happened (for the 5-10 minutes), I did turn the truck off at one point and there was no change. Now, I would definitely rather see if this is the case when it acts up again just to be sure, but if that is the case, not going into gear whether the engine is on or off, what would that tell us?

Thanks for the help.

 

As Lead Head stated, it will give a clue as to whether the clutch or transmission is the issue ...

If it goes into gear with the motor off, it points to a clutch, if it does not go into gear with the motor off it points to transmission.

-Enjoy
fh : )_~

 

Got you. Thanks for the clarification. I was hoping it wouldn't be one of those two things, I'd rather it be the slave cylinder or something I can at least grasp.

This may be a dumb question, or just a naive one, but if I find that it points to a transmission issue (or a clutch issue, since they are both intertwined), what exactly are we talking about here? What I am trying to figure out is whether I can fix the issue myself, or if I will need someone to do it. I have done all the repairs myself this far, but those repairs weren't as in depth as this could be (fuel pump replacement, master cylinder replacement, air plenum removal, and some odds and ends).

So, if it is looking like I will need a costly specialist, I will need to prepare for that, or prepare to find a new vehicle. Thanks for the help.

 

The only dumb question is the unasked one ...

Naive is acceptable, no one knows everything, I myself am Naive on the F150.

I or anyone else cannot tell you whether you are capable of doing the repairs, only you can.

However, If you're handy, have the tools, some one here can most likely walk you through your repairs ...

A clutch change (or slave change on that truck) requires pulling the transmission, this is a fairly easy repair, if you have the place and tools.

As for Transmission repair ... I have to leave that to those that know what transmission you have.

-Enjoy
fh : )_~