Hello everyone. I've been browsing the forum from the shadows and decided to take the plunge and join.

I have a question about an issue I'm having with my 89' F-150 transmission.

Story:
The wife and I were out riding around in the snow about a week ago and everything was going fine. There was no drift busting or any "out of the norm" driving going on, and on our return trip home, the truck came to a sudden stop (as well as it could have on ice/snow) as if someone had locked up the brakes. The truck engine shut down. So, my first thought was maybe I had broken one/both of the hubs so I got out and put the the hubs into the free/unlocked position and just figured I had dumped the clutch and stalled the truck. After unlocking the hubs I got back in the truck, pressed the clutch in, started it and placed the truck into first gear. Slowly started releasing the clutch and it sounded as though the engine was bogging down, so I pressed the clutch back in and the engine picked back up.

Now I am completely confused at this point. So thinking maybe something was wrong with the transmission, I put the M5 in neutral and started to release the clutch to get back out and crawl under the truck, and the truck started to move forward as if it was in gear?

Long story short, I was able to get the truck home with the transmission in neutral and the transfer case in 2-HI.

Fast forward to today: I pulled the floor board covering back and was able to remove the doghouse cover and exposed the top of the transmission. Pulled the shifter along with the "tower" out of the truck trying to see if I had broken a shift fork. Nothing was broken from what I could see. I fired the truck up with the tower off to see if I could catch something while trying to let off the clutch. No go. Didn't see anything happening but the truck tried to stall. Put the transfer case and transmission in neutral and let off the clutch. The transmission gears started spinning and the truck, as expected, didnt move nor did it try and stall.

So, now I'm here seeking some advice. This is my first Light Duty pickup truck, as I usually only drive the F-250 with the 7.3L Turbo Diesel and mess with the ZF series transmissions.

Any advice would be greatly appreciated and I will apologize before hand about the "windy" post.

 

Sounds like a folk has jumped over the syncronizer and the syncronyzer has a gear engaged. When you put it in nuetral it pulls because its already in gear. When you moved the shifter to put it in gear, you are engaging 2 gears.

 

So worth trying to rebuild or should i just be looking for a replacement? Can this be fixed without a rebuild i guess is a better question. I can drop the transmission And transfer case tomorrow if need be.

 

Here's a thread with pictures of the inside of the trans.
It doesn't show the tail shaft area where 5th gear and reverse are.

https://www.ford-trucks.com/forums/1...l#post12094418

There are 3 shifter forks. One for 1st and 2nd gear, another fork for3rd and fourth and 5th gear and reverse share the same fork.

The forks move a clutch hub to engage each gear. You can use your hand and move the clutch hubs forward or backwards. In the center position the gears are not engaged.

Verify the clutch hubs are all in the center position. In this position only the transmission front input shaft turns if the clutch pedal is not engaged and the engine is running. If you engage the clutch pedal with the engine running, the input shaft should not rotate.

You said you drove the truck home with the transmission in neutral and in 2hi.

That would indicate a gear was still engaged. What gear did it feel like?

 

If I was to guess, and by the feel and sound of the truck while driving, it appeared to me at least that it was in second gear.

 

I went out to mess with it again, because its bugging me that I cant figure it out. With the engine off, I put the trans back into neutral or what is supposed to be neutral, and then removed the shifter and shift fork assembly again. The slip ring just before the biggest gear I can move back and forth with a little effort. The one closest the input shaft I can jiggle and maybe get a millimeter's worth of movement out of it. I can't reach anything on the rev fork area as its still in the truck right now.

That picture you posted looks exactly like the inside of mine. In a nut shell, I know beans about this transmission.


I dont think i can post pictures yet, but if you look at the picture in the link above, It's the synchronizer in front of the "5th" gear that I can move. The other I cannot.

 

The pieces with the brass colored teeth are the syncronizers.

The red arrows point to what I call the hubs the forks engage and move.

The picture shows white arrows calling the hubs syncronizers which is not correct.

The hub slides over the syncronizer then the teeth for that gear.

The hub should slide to engage each gear with some resistance.
If two gears were engaged at the same time, the transmission
would bind and the output shaft would not turn so your problem
sounds like one gear is engaged and most likely a forward gear because
you say the truck moves forward.

I redid the picture posted below. The red arrows point to the actual gears.

 

Ok, so I pulled my transmission and transfer case today and took it down to a good local transmission shop today. Took a little more then an hour to do so. Anyway, the guy at the shop took the transmission and cleaned it up and then started his inspection. After about an hour he called me to inform me that my truck was stuck in 4th gear, the shift forks were worn, and here's the best, the input shaft was welded to the output shaft. He said there is no fixing this, and he is currently searching/pricing a remanufactured transmission.

Thank you for everyone's help in here. I'll update again once I start the reassembly.

 

ThatGuy79-
I'm new here too after lurking. It's a really good site. I am a pro at giving unsolicited and slightly off-topic advice. Having owned 2 F150's with the M5od-2 transmission, I know it is the weak link in these trucks (both mine were 2wd). I am currently considering upgrading the trans behind my 300ci to a zf-5 (the type you are familiar with). They're bullet-proof, and may bolt up to your engine/t-case with minimal effort. I'm sure someone else can advise on where to find a good thread for the 4x4 conversion.

 

I believe there's a difference between the M5ODR2 and the ZF5's length in regards to the tail shaft housing? I could be wrong but i think that the ZF donor would also have be from a 4x4?

 

There are what appears to be some great deals on rebuilt m5odr2 transmissions on ebay. Go to ebaymotors.com and type in "5 speed ford transmission".

Yes, wherever you get a transmission it has for a 4x4.

 

Thank you. I'll check out eBay tonight. Found 3 M5ODR2 transmissions in a local junk yard, but none of them were 4x4.

 

Where are you located? Local members might be of help

 

Around Peoria, IL

 

PM Justin (JKCat69 or something like that) he is in the Vernon Hills area, and knows wher a lot of parts and boneyards are.

Put it this way...He found me a Hurst Shifter for my M5...lol