Need tranny help
Thread Starter
|
New User
Joined: Sep 2007
Posts: 5
Likes: 0
Need tranny help
I have a 78 F250 with the 4 speed (granny Low) tranny. Yesterday I got off the interstate pulling a trailer and when i went to down shift i could move the shifter but the tranny stayed in 4th gear. It seems something sheared off inside. I've never dug into one of these before so I'm not real sure what it could be. I limped the truck to one of the fire stations (that is my profession) where i could leave it until i get another truck and trailer to tow it home. This truck is my baby, it has been in my family since new and only has 48,000 original miles on it. I would like to fix it myself. I don't let to many people work on her. if anyone has some ideas or helpful info i would apprieciate it.
Bob
Bob
Postmaster
Joined: Aug 2000
Posts: 3,312
Likes: 1
From: Eldorado Ca. USA
Which 4 speed do you have? First off, I would pull the shifter out, see if the innards are in order. A t18 you have to unscrew the shifter retainer, the NP435 you will have to push down, 1/4 turn, and will pop out. Take a looksie down the hole, you will see your shift rails. The shift rail for 3/4 is on the right hand side. Take a large screwdriver, align all the shift rails up so they all center up in the middle. That will put you into neutral. Check the end of the shifter, make sure nothing has sheared off. If it has, a trip to the junkyard to find another is in order.
Thread Starter
|
New User
Joined: Sep 2007
Posts: 5
Likes: 0
Thank you for the reply. I guess I assumed I had the T18. This is a 2 wheel drive stock F250 custom. I have my tow rig all set up so i will be taking my truck home in the morning after I get off shift.
Super Moderator
Joined: Apr 2004
Posts: 34,530
Likes: 2,833
For '78 your 4 speed should be either a NP435, non-synchro first, R is to the right and down, or the T19, synchro first, R is to the right and up. It is also possible you have a T 18, non-synchro first, either up or down for R due to use of two different shifter assemblys.
T 18 will have 13-01 cast into them, T 19 will have 13-09.
Anyway, removal of the shifter and cover may tell your tale here. For the NP 435, it's push down on the stick and turn. The others have a cover held on by screws.
Seems like the shift forks wear, or some little nylon part falls off, etc.
Edit: Took too long to post, see previous.
T 18 will have 13-01 cast into them, T 19 will have 13-09.
Anyway, removal of the shifter and cover may tell your tale here. For the NP 435, it's push down on the stick and turn. The others have a cover held on by screws.
Seems like the shift forks wear, or some little nylon part falls off, etc.
Edit: Took too long to post, see previous.
Super Moderator
Joined: Apr 2004
Posts: 34,530
Likes: 2,833
This here is the site, they have a schematic link for the T18 and a rebuild guide for the NP435. These should have pics etc for the parts you may need.
Good luck.
Removed by FTE staff, every time it is placed in a spot it will be removed do not link to that site.
Good luck.
Removed by FTE staff, every time it is placed in a spot it will be removed do not link to that site.
Postmaster
Joined: Aug 2000
Posts: 3,312
Likes: 1
From: Eldorado Ca. USA
You don't get banned for linking other sites, unless you are cheerleading for them.
And what "old" transmission has screws holding in the shifter? Either the top unscrews, or the tin comes off.
My guess is the end of the shifter broke off.
And what "old" transmission has screws holding in the shifter? Either the top unscrews, or the tin comes off.
My guess is the end of the shifter broke off.
Super Moderator
Joined: Apr 2004
Posts: 34,530
Likes: 2,833
Pics, parts from diff site.
"..cover held on by screws." That would be the top cover, not really the shifter. It appears the stick comes out by unscrewing the cap at the bottom of the stick. Not sure what you can do in this situation by just pulling the stick? But, if it's broken as you suggest, I guess that would tell the tale.
Sorry to cause confusion.
Parts for the T18 & T19 Transmissions
"..cover held on by screws." That would be the top cover, not really the shifter. It appears the stick comes out by unscrewing the cap at the bottom of the stick. Not sure what you can do in this situation by just pulling the stick? But, if it's broken as you suggest, I guess that would tell the tale.
Sorry to cause confusion.
Parts for the T18 & T19 Transmissions
Trending Topics
Ford Parts Specialist
Joined: Nov 2006
Posts: 88,826
Likes: 787
From: Simi Valley, CA
Welcome to FTE
New Process 435:
When the nylon inserts on the shift forks break apart, the trans can no longer be shifted.
Sometimes the pieces fall into the gears, jamming them up.
There are two different inserts:
2) D2TZ7C430B ~ Used on the 1-2 shift fork.
2) C2TZ7C430B ~ Used on 3-4 shift fork.
Ford just obsoleted these inserts, but they are available from dozens of obsolete parts vendors.
JST Automotive in Lebanon TN has both these parts: 615-443-3086
Green Sales Co. in Cincinnati OH has both these parts: 800-543-4959.
Also look at the cap that retains the shift lever, it has two notches on it.
Peeps do not know that this cap must be pressed down on and then held while it's turned 1/4" to remove it.
Trying to turn the cap without pressing down, tears out one or both of the notches.
B8T7220D .. NP435 Shift Lever Retaining Cap / This part is still available from Ford.
MSRP: $7.59 / FTEpartsguy.com price: $4.64
MasterBeavis: Cheerleading or not, FTE guidelines do not allow members to post links to rival sites with the exception of Slick 60's.
New Process 435:
When the nylon inserts on the shift forks break apart, the trans can no longer be shifted.
Sometimes the pieces fall into the gears, jamming them up.
There are two different inserts:
2) D2TZ7C430B ~ Used on the 1-2 shift fork.
2) C2TZ7C430B ~ Used on 3-4 shift fork.
Ford just obsoleted these inserts, but they are available from dozens of obsolete parts vendors.
JST Automotive in Lebanon TN has both these parts: 615-443-3086
Green Sales Co. in Cincinnati OH has both these parts: 800-543-4959.
Also look at the cap that retains the shift lever, it has two notches on it.
Peeps do not know that this cap must be pressed down on and then held while it's turned 1/4" to remove it.
Trying to turn the cap without pressing down, tears out one or both of the notches.
B8T7220D .. NP435 Shift Lever Retaining Cap / This part is still available from Ford.
MSRP: $7.59 / FTEpartsguy.com price: $4.64
MasterBeavis: Cheerleading or not, FTE guidelines do not allow members to post links to rival sites with the exception of Slick 60's.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 6 Best Deals Available on New Fords & Lincolns Right Now
Brett Foote
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level
Verdad Gallardo
Top 10 Fords at 2026 Carlisle Ford Nationals
Joe Kucinski
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Postmaster
Joined: Aug 2000
Posts: 3,312
Likes: 1
From: Eldorado Ca. USA
Who is Slick 60? [edit] nevermind, 30 seconds on google found my answer. So why is this guy different than anyone else?
I have inspected a few NP435s for resale, some still had those nylon bushings on the shift forks, some were worn off. Both did not seem to have any unusual issues with shifting. I still suspect that the end of the shifter has broken off. If the gears had something jammed in them, the truck would not move, nor would he be able to move the shifter. If a shift fork was broken, it would be possible to shift into two gears simultaneously, that would instantly lock the transmission up, and stall the engine every time you let the clutch out. With the shifter, do you feel any remnants of a shift gate(H pattern), or does it free float?
I have inspected a few NP435s for resale, some still had those nylon bushings on the shift forks, some were worn off. Both did not seem to have any unusual issues with shifting. I still suspect that the end of the shifter has broken off. If the gears had something jammed in them, the truck would not move, nor would he be able to move the shifter. If a shift fork was broken, it would be possible to shift into two gears simultaneously, that would instantly lock the transmission up, and stall the engine every time you let the clutch out. With the shifter, do you feel any remnants of a shift gate(H pattern), or does it free float?
Thread
Thread Starter
Forum
Replies
Last Post
fordor
Clutch, Transmission, Differential, Axle & Transfer Case
5
Jun 7, 2010 12:23 PM
tomtek
Explorer, Sport Trac, Mountaineer & Aviator
9
May 12, 2010 10:40 AM
ANTIDodge
1973 - 1979 F-100 & Larger F-Series Trucks
4
May 14, 2008 09:42 AM
unioncreek
Clutch, Transmission, Differential, Axle & Transfer Case
3
Jan 1, 2002 05:30 PM
Bob Pringle
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
3
Dec 23, 2000 10:31 AM