Destroyed np203?
Thread Starter
|
Freshman User
Joined: Nov 2016
Posts: 26
Likes: 0
Destroyed np203?
Still learning on the 500$ 79' f150 only to find the truck will only drive in "low lock" in low, and hi lock it sputters and doesnt want to pull, in hi it has no pull and a slight grinding (assuming the chain)
The motor isnt in great shape to start, and the transmission doesnt like to shift on its own. Not sure where to start on all this
Info on truck
351m
3 speed auto
Np203 (for some reason has locking hubs in front)
The motor isnt in great shape to start, and the transmission doesnt like to shift on its own. Not sure where to start on all this
Info on truck
351m
3 speed auto
Np203 (for some reason has locking hubs in front)
Moderator & parts slinger
Joined: Feb 2007
Posts: 50,144
Likes: 5,780
From: S/W Missouri, Polk county
Have you confirmed you have a NP 203? Look at the silver/blue tag on the front. Figure that out 1st.
If it "sputters" then its an engine problem, I'd get that fixed first. Basic tune up stuff like plugs, plug wires, rotor bug, dizzy cap.
But it you hear grinding then that can be a bad sign. Chain stretch and slip is common on a NP203. Drain the fluid and see what it looks like (metal shavings?) NP 203 has oil, NP 205 has 80/90 gear lube.
Np 205 is pretty much bomb proof. Maybe a fluid, filter change and modulator ck is in order for the trans?
If it "sputters" then its an engine problem, I'd get that fixed first. Basic tune up stuff like plugs, plug wires, rotor bug, dizzy cap.
But it you hear grinding then that can be a bad sign. Chain stretch and slip is common on a NP203. Drain the fluid and see what it looks like (metal shavings?) NP 203 has oil, NP 205 has 80/90 gear lube.
Np 205 is pretty much bomb proof. Maybe a fluid, filter change and modulator ck is in order for the trans?
Laughing Gas
Joined: Oct 2015
Posts: 990
Likes: 109
From: Dallas, OR
They do have a conversion kit for the 203 which changes them from full time 4WD. Mine has the locking front hubs too, I just haven't taken it off road yet to confirm that it has been converted like I think it has. I could just put all four corners on jack stands, but what fun is that?
Thread Starter
|
Freshman User
Joined: Nov 2016
Posts: 26
Likes: 0
They do have a conversion kit for the 203 which changes them from full time 4WD. Mine has the locking front hubs too, I just haven't taken it off road yet to confirm that it has been converted like I think it has. I could just put all four corners on jack stands, but what fun is that?
lo and hi doesnt work at all
Laughing Gas
Joined: Oct 2015
Posts: 990
Likes: 109
From: Dallas, OR
Sorry, that info was more aimed at your question about why you had front hubs. I haven't played with the internals of a T-case too much, so I don't have much in the way of helpful suggestions there.
Moderator & parts slinger
Joined: Feb 2007
Posts: 50,144
Likes: 5,780
From: S/W Missouri, Polk county
Modulator ck:
Check the vacuum modulator and the line that goes to it.
Check the line for kinks or other problems, make sure it hasn't come off.
If the line checks out, take the line off where it connects to the modulator. If trans fluid leaks out, its bad. If no fluid, it still could be bad. They're simple to replace, disconnect the vacuum line, remove one bolt that holds the clamp in place and the modulator comes out. It has an o-ring seal.
Modulators are identified by the color of the stripe. Pretty much the "go to" one is the black stripe. If they don't show that one in the catalog, go with the green stripe. Avoid the pink stripe. That one is a dual diaphragm version that has two vacuum line going to it. If by chance you have one of these, replace it with one of the other two and use the vacuum line that goes to direct manifold vacuum, cap the other line.
When you pull the modulator out, be careful. There is a pin that goes in the modulator. Sometimes it comes out with the modulator, sometimes it stays in the tranny. If it comes out, don't lose it.
Check the vacuum modulator and the line that goes to it.
Check the line for kinks or other problems, make sure it hasn't come off.
If the line checks out, take the line off where it connects to the modulator. If trans fluid leaks out, its bad. If no fluid, it still could be bad. They're simple to replace, disconnect the vacuum line, remove one bolt that holds the clamp in place and the modulator comes out. It has an o-ring seal.
Modulators are identified by the color of the stripe. Pretty much the "go to" one is the black stripe. If they don't show that one in the catalog, go with the green stripe. Avoid the pink stripe. That one is a dual diaphragm version that has two vacuum line going to it. If by chance you have one of these, replace it with one of the other two and use the vacuum line that goes to direct manifold vacuum, cap the other line.
When you pull the modulator out, be careful. There is a pin that goes in the modulator. Sometimes it comes out with the modulator, sometimes it stays in the tranny. If it comes out, don't lose it.
Thread
Thread Starter
Forum
Replies
Last Post
marioc956
Clutch, Transmission, Differential, Axle & Transfer Case
1
Jul 24, 2007 04:28 PM
wyazel1
Clutch, Transmission, Differential, Axle & Transfer Case
5
Mar 26, 2007 07:39 PM
