Hi all!

New to the forum, but I've had my truck for a number of years...1979 F-350 w/ 351m and manual trans.

Anyway, I was plowing with the beast today and suddenly couldn't shift into any of the forward gears. I could only get back into reverse, so I had to drive down the street backwards, turn around, drive back down the street, pull into the driveway, and park the truck. (No small feat in reverse, in a tight driveway, in a lifted 350, with way to go forward and start again if i messed up...)

What do you think happened? I messed with it for awhile after it was safely parked (pressed/released the clutch, shifted the t-case, etc) but only succeeded in crushing my trash can when i popped into reverse w/o using the clutch. It felt like something was blocking the shift lever from going into any of the other gears.

Any idea what trans came stock in these trucks? Should I think rebuild/ replace, or is it something easily fixed? I'm pretty good with diagnosing and fixing the beast, but trans work is new to me...

 

You need to pull the top off your transmission and look at your shifter forks. You can do this without removing the transmission.

 

Most had a NP435, I think a few had T18

 

Welcome to FTE

Look on your Warranty Plate (located on the left door face below the latch) for the TRANS Code.

A = New Process 435 4 speed.

F = Warner T-18

P = Warner T-19

Once discovered what manual transmission you have, we'll go from there.

 

Since I'm anxious to get the beast back on the road, I grabbed a flashlight and looked at the warranty plate on the door frame after work. The VIN is intact, but all the codes are either worn away, or weren't there in the first place (the sticker is in great shape.)
I looked up the VIN and it comes back to an F-250, not an F-350. (numberdummy, care to verify? VIN= F26HEEE1377) So, now I have a truck ID problem...I looked for the VIN on the front frame, but couldn't locate it.

So while I figure out what TRUCK I have, I'll try and address the trans problem...Is there a number anyplace on the trans that would let me know what it is?

As far as the truck goes (and maybe I should start another ID thread), here's what I know:

1.) The cab (and therefore the warranty plate) is probably different from the rest of the truck. The original fenders and hood are metallic green, the cab was white.

2.) There's no VIN that I can see on the driver's door itself (which wouldn't matter much, seeing that the original driver's door was brown...)

3.) The truck has D60's, front and rear

4.) The motor is a 351m

5.) The truck has square headlights

6.) There is a factory "toolbox" in the driver's side rear quarter panel, just behind the cab.

Any ideas? Should I look harder for a VIN on the frame or anywhere else?

 

Don't go by the vin, go by what you actually have. Take a peek at your transmission. The shifter retainer for a t-18 screwws on, the retainer for a NP435 has a stamped sheet metal piece that you need to press down on, and turn to the (left?) for it to come off. Once you get the shifter out, take a peek down there with a flashlight to see whats going on if anything. You will see three thingermabobs, with a channel in the middle of each of them. When you are in neutral, the slots will all line up in the middle. I suspect that possibly one of your shift fork arms has broken off or a damaged syncro, however I am not a trans expert. You can pull off the PTO cover and inspect for broken pieces in the bottom of the trans. You can take the top of the transmission off, if you pull up your carpet, and remove the trans tunnel carpet. Make sure you get everything squeaky clean prior to opening up the transmission.

Did you try putting it into gear while letting out the clutch? Is it refusing to go into all forward gears? Have you tried coasting the truck, or had somebody pull you forward and tried shifting?

These transmissions are pretty tough. You can buy a used one for around $100-200 that will last you a very long time if it was properly maintained, or at least not abused. A bearing kit is $100 or so, syncros are going to run ya another $200 or so. It is possible to rebuild it yourself, you only need a couple of special tools (a press for starters) but without finding out what is wrong with your trans first, I would hesitate to rebuild it, hoping that whatever you did fixed it. My vote is a used trans. They for the most part were the same up till '86 in the NP435 flavor, the t18 morphed into the T19A, which had a syncronized first gear. Two(three) different gear ratios, one for gas, one for diesel(4:1), one for?? T18-has a 1301 on the side, a T19 will have a 1309. The 435 has an aluminum top cover.

 

What is the VIN on the registration?

The white Certification Label is not the Warranty Plate (W/P).

The W/P is metal, the codes were stamped (embossed) on it originally, so they cannot be "worn" away.

F26 = F250 4WD Pickup

H = 351M

E = Mahwah NJ Assembly Plant

EE1377 = 1979.

There is no such thing as a factory tool box on the drivers (left) side of the quarter panel..all were on the passenger (right) side.

All 1979 F350 4WD's had Dana 60's front & rear, some F250's also came this way.

The Warner 4 speeds were fairly trouble free, the New Process 435's were not.

The NP's cap that MasterBeavis is speaking about, has two notches in it and is retained by two pins that protrude from the shift tower.

The cap must be pressed down, then turned to remove the lever. Peeps don't know about the press down part, try to turn it...which tears out the notches, rendering the cap useless.

On each shift fork are two nylon inserts. These are notorious for breaking apart, the pieces can fall in between the gears, jamming them up.

Even if the syncro's are worn, usually the trans can still be shifted, so I doubt the syncro's themselves are causing the problem.

My guess is, it's either that shift lever retainer cap, and/or the nylon inserts that have failed. One old timey mechanic told me that if the inserts go missing, the trans can no longer be shifted.

The 1-2 shift fork inserts (D2TZ7C430B) are different than the 3-4 inserts (C2TZ7C430B). These are now obsolete, but 100's are still available from dealers and obsolete parts vendors.

If you need these, I can find them, no problemo.

The cap (B8T7220D) is still available from Ford and retails for less than 8 bucks.

 

Wow, it must have been later than I thought when I posted that last night, lol.

Of course the toolbox is on the passenger side, I don't know why I said driver...

The VIN on the registration is the same one I posted from the cert sticker, which would mean the title would read that way, too...hmmm...wish I could find that frame number (or warranty plate, for that matter...). The title and reg both say f-350, so someone screwed up somewhere.

As far as the trans goes, I'll poke around under the truck tomorrow in daylight and see what I can come up with.

The shifter won't go into any of the forward gears; even after rolling, clutching, unclutching, revving and forcing (gently), etc. I wish Haynes had a better teardown of the trans, I haven't played with one before. I guess it's time for the factory manual on CD. Ebay, here I come...

 

As far a transmissions go, these are easy to work on. They are large with room to work and come apart easy. But before I tore into it, I would pull the cover on the floorboard and take the screws off the boots, unscrew the gearshift and transfer case ***** and remove the access panel, then unbolt the top off the transmission (about ten bolts). You will be able to see whats wrong from here. This will take less than an hour and you will know if the trans has to be pulled. I will guess and say it is probably just a shifter problem unless something broke and fell into the gears.